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Ctene Sensations of the Arctic Ocean

Arctic Sea Ice Ecology - Thu, 05/23/2013 - 00:40

One of the goals of Andy Juhl’s and Craig Aumack’s Arctic research is to determine the role of ice algae as a source of nutrition for food webs existing in the water column and at the bottom of the Arctic ocean. During their fieldwork these Lamont-Doherty Earth Observatory scientists are deploying a plankton net, a common tool used by ocean scientists to catch tiny marine plants and animals in the water column, to collect live plankton for identification and examination in the lab. They’re hoping to determine the different kinds of organisms active in this part of the Arctic Ocean and their food web feeding connections, or who’s eating whom by testing the organisms to see if they contain algae in their guts and muscle tissues.

This information is important because it will provide a baseline understanding of the connection between the algal community in the sea ice and the underlying ecosystem, and how it functions. Once this is understood, scientists may be able to better understand and predict changes that could occur in the marine food web as Arctic snow and ice cover changes.

A few days ago we caught the comb jellies in this video near shore at a depth of about four meters. Though comb jellies have the same type of gelatinous body as a jellyfish, they belong to a completely different phylum called ctenophores. Known for being vicious carnivorous predators, ctenophores use rows of comb-like cilia to propel themselves through the top of the water column and prey on smaller organisms, such as zooplankton. Ctenophores are found throughout the world’s oceans, including Arctic waters — quite a few of appeared in the holes we’ve bored into the ice this week.

These two comb jellies were filmed under a microscope in our lab. Each one is just a few millimeters long, though they can grow to be about 10 cm, sometimes larger. You can also see small copepods, a type of zooplankton and favorite food of ctenophores, zipping around the screen. Seeing a lot of ctenophores in the upper water column is a good indicator that they are feeding extensively on copepod larvae, who in turn are feeding on ice algae. This is an example of a few of the connections that make up the foundation of the food web in this fragile, yet biologically productive ecosystem.

Click here to view the embedded video.

On Wednesday Andy and Craig answered responded to questions about their research during a Reddit “Ask Me Anything” session. While the event is over, the session remains on Reddit and we encourage you to check it out to learn about our research and life in Barrow, Alaska.

For even more information on our project, visit http://lifeintheice.wordpress.com or follow Lamont-Doherty Earth Observatory and the hashtag #LDEOarctic on Twitter.

Collecting Core Data About Arctic Ecosystems

Arctic Sea Ice Ecology - Mon, 05/20/2013 - 12:53
Andy Juhl collects temperature data from a core, while Craig Aumack drills another.

Andy Juhl collects temperature data from a core, while Craig Aumack drills another.

Our team spent most of Friday on the Arctic sea ice, drilling and sampling ice cores at our main field site. For each core collected, Lamont-Doherty Earth Observatory scientists Andy Juhl and Craig Aumack take a number of different physical, chemical and biological measurements that characterize the ice and the organisms living inside it. Some of these measurements are recorded right away in the field, others will be taken later using pieces of the cores that we bring back to the lab.

Two of the physical measurements Andy and Craig record are the temperature and salinity of the ice. “Temperature is a critical parameter that controls the rate of almost all biological processes in the ice — almost everything happens slower when it’s colder, and parts of the ice can be colder than others. And if you know the temperature and the bulk salinity of the ice you can calculate how much brine volume there is within a given layer in the ice,” Andy explained.

Brine volume is an important measurement because algae live in brine channels in the ice. As ice gets colder, there’s less brine volume within it, meaning there’s less room for algae to grow. Andy and Craig also measure the concentrations of plant nutrients in the ice cores, including nitrate, ammonia, phosphate and silicate – some of the same elements that plants growing on land need. And, as with terrestrial plants, nutrient availability in sea ice is a factor that controls the growth of algae inside the ice.

 the objects of our affection. The brown areas are the bottom of the cores and indicate the presence of algae in the ice.

Ice cores: the objects of our affection. The brown areas are the bottom of the cores and indicate the presence of algae in the ice.

Other measurements, such as particulate organic carbon (POC) and dissolved organic carbon (DOC), Andy and Craig take in the lab will reveal the amount of carbon, or organic material in the ice. In addition to algae, carbon found in the ice comes in the form of non-living materials, such as bits of organic detritus from the tundra that become trapped in the ice. Finally, samples are collected for microscope work so that project scientists can identify the different types of organisms found throughout the ice.

All of this information varies in any single ice core from the top to the bottom, and based on where it is drilled. By taking consistent measurements from each ice core in different locations, project scientists can develop an in-depth understanding of the dynamics of the Arctic algal ice ecosystem – and how it may be changing.

Our group spent Saturday and Sunday in the lab processing samples from last week and preparing equipment, including mounting a camera system on our small remotely operated vehicle (ROV). We’re heading back onto the ice early Monday morning with the ROV and are looking forward to working in temperatures that may reach 35F.

For more information on our project, visit http://lifeintheice.wordpress.com or follow Lamont-Doherty Earth Observatory and the hashtag #LDEOarctic on Twitter.

What Lies Beneath Arctic Ice?

Arctic Sea Ice Ecology - Sun, 05/19/2013 - 02:38

On Thursday we lowered a camera into an ice borehole to get a look at the underside of the ice. In the following video, you can clearly see the algae living in the bottom of the ice due to their pigments, which they use to harvest light.

These organisms are not frozen into the ice; they’re living creatures that grow and thrive in tiny pockets of brine inside the ice. You might notice in the video that the underside of the ice is not flat, this is probably a reflection of variability in physical conditions in and above the ice, such as snow cover thickness.

Click here to view the embedded video.

While watching this video, Andy Juhl and I discussed how cool it is that there are vibrant communities growing in extreme environments. “One of the lessons that research in polar regions has taught us is that we need to broaden our definition of where life exists and thrives. In the Arctic, we have life growing inside ice, at below freezing temperatures. This means that we know to look in more unusual places for science of life and that’s one of the interesting things we learn by doing this kind of work,” Andy said. “Ice is not necessarily an inhospitable habitat, and on other planets where we see ice, that’s a place where we should probably look for signs of life.”

The second film shows a bit of life on the seafloor. This video was shot near shore where the water depth is about 8 meters, so it’s fairly shallow; water temperature here is -2C. The bottom consists of soft mud and it looks like there are deposits of algae that probably came from the ice on the surface of the bottom (those are the darker areas). There’s a variety of bottom dwelling organisms that live in the mud, such as the isopod that wanders across the mud in this clip. We don’t yet know how large the isopods are or what they eat; scientists on our team are trying to figure out a way to measure an isopod in situ or capture one to examine in the lab.

Click here to view the embedded video.

As our work in Barrow progresses, we’ll continue to post more videos so that you can get a sense of the life that makes up this fascinating ecosystem.

For more information on our project, visit http://lifeintheice.wordpress.com or follow Lamont-Doherty Earth Observatory and the hashtag #LDEOarctic on Twitter.

 

Ice Capades

Arctic Sea Ice Ecology - Fri, 05/17/2013 - 05:24
Scientist Andy Juhl makes notes at our first field site about snow depth and distribution.

Scientist Andy Juhl makes notes at our first field site about snow depth and distribution.

Fieldwork is exciting and inspiring, leading scientists to new ideas, places and observations about how the world works. Spring on Alaska’s North Slope provides an especially productive environment for fieldwork. When the sun never sets, it’s easy to linger in the field and the lab long into the well-lit night.

Our team spent about six hours on the Arctic sea ice Thursday, enjoying blue skies and temperatures in the low teens, while making observations, maintaining sampling sites and taking measurements. Most of our time was spent at two different field sites Andy and Craig established near Point Barrow, a narrow spit of land that’s the northernmost point in the United States. Traveling to these sites involves loading up two sleds with all of the sampling equipment, hitching the sleds to snowmobiles and carefully traversing the sea ice on said snowmobiles, which, I discovered today, is extremely fun.

Andy, Kyle and Craig prepare to finish drilling a hole in the ice.

Andy, Kyle and Craig prepare to finish drilling a hole in the ice.

One of the research questions Andy and Craig are exploring in Barrow is how the amount of snow covering sea ice might affect the diverse species of algae living in and just below the ice. A thin snow cover allows more sunlight to reach the algae; a thicker snow cover creates a darker environment. As in any ecosystem, many different species are competing for light and nutrients. For this study, Andy and Craig want to see how changing one factor in the Arctic sea ice ecosystem – the amount of available light – might allow some organisms to grow better and become more prevalent than others.

Last week Andy and Craig set up an artificial snow gradient at our first field site, where different snow depths cover the ice in a small, isolated area. Ice cores were drilled here on their first day and Andy and Craig will repeat this same exercise later in May. Collecting data over these specific time intervals will enable them to see how snow depth and distribution affect the community of organisms living in the ice. This information will provide an idea of what might happen to the entire ecosystem if more light is introduced via less snow cover in the future.

At the second field site, scientists used an auger to drill a hole in the ice, which is currently about four feet thick. Then a camera was lowered into the hole, with a live feed to a computer so we could see what was happening in the sea directly below us. A thick layer of algae covered the underside of the sea ice and once lowered eight meters to the sea floor, the camera revealed isopods (small crustaceans), jellyfish and a few unrecognizable members of the Arctic marine ecosystem.

Lowering the camera into the -2F sea.

Lowering the camera into the -2C sea.

“We do the camera work because there’s no substitute for seeing the ecosystem intact. We need to get cores in order to collect samples, but you get a really different impression of the ecosystem with the camera,“ Andy explained.

Later in the afternoon we searched the ice for a sampling station Andy and Craig used last year, but were unable to find it. The area had become covered with huge pressure ridges, large fragments of ice that pile up when sheets of ice collide, which are hard to cross on a snowmobile. At one point fresh polar bear tracks meandered among the ridges, but we never caught sight of the bear who made them.

For more information on this project, visit http://lifeintheice.wordpress.com or follow Lamont-Doherty Earth Observatory and the hashtag #LDEOarctic on Twitter.

Settling in to Work and Life in Barrow

Arctic Sea Ice Ecology - Wed, 05/15/2013 - 23:00
The Barrow Arctic Research Center, home of our lab space.

The Barrow Arctic Research Center, which houses our laboratory.

While I arrived in Barrow, Alaska on Tuesday, Lamont-Doherty Earth Observatory scientists Andy Juhl and Craig Aumack, and graduate student Kyle Kinzler from Arizona State University, got here one week ago. They took a few days to unpack and set up their lab (everything they need to work here must be shipped to Barrow in advance), scout locations for sampling on the ice and ensure that their tools and equipment are working properly before they begin their fieldwork.

Our team alternates days in the lab and days on the ice. The lab space we’re using is a bit north of town at the Barrow Arctic Research Center (BARC), a newly constructed facility where the National Science Foundation leases space for its researchers. Scientists wishing to work in and around Barrow can use BARC as their home base. At the moment the building is fairly quiet as the only other occupants are a group of international graduate students being trained on how to conduct sea ice research.

Today was a lab day, where recently collected samples were processed, experiments performed and preliminary data analyzed. Fieldwork is just the beginning of a research process that can take several years. The majority of the samples and data collected here won’t be examined until scientists are back at their respective institutes, where it can take months or longer to analyze all of their samples and data and then write up the results. But, to ensure that their research is on the right track, a few experiments and analyses are done while in Barrow.

Craig holds a bag containing water from a melted ice core that he drilled a few days ago. The water looks murky due to the presence of algae.

Craig holds a bag containing water from a melted ice core that he drilled a few days ago. The water looks murky due to the presence of algae.

This afternoon I spent time in a zero degree walk-in freezer talking with Craig Aumack, who’s conducting experiments to learn more about the organisms living in Arctic sea ice. Each year, as soon as any light is available, algae start growing in the ice and continue to bloom through the onset of spring and the Arctic’s long summer days. Algae prefer to live in the bottom of the ice, because, like all plants, they need light and nutrients, and these are plentiful at the sea-ice interface.

Craig’s experiments are called settling experiments, and these help him learn what happens to the organic materials and organisms living in the sea ice when they’re released into the ocean. Craig wants to determine the rate at which these particles sink down through the water column; this information reveals whether particles are more likely to be consumed while falling through the water column or once they accumulate on the seafloor. Particles that sink slowly are more likely to be eaten by zooplankton, tiny marine animals, while those that fall to the bottom will be consumed by worms, crustaceans and mollusks.

Settling experiments must be done in a freezer because organisms that call ice home would quickly die if exposed to a 70-degree temperature difference. Though extreme temperatures can also cause humans to become a bit uncomfortable, we’re able to don parkas and puffy jackets to protect us; algae don’t have this luxury. So, Craig replicates the conditions in which ice algae thrive, and bundled up, works in a frigid environment.

Andy Juhl was happy to explain this experiment and their research further, fortunately outside of the freezer. “There’s a whole ecosystem living inside the ice. Ultimately, we want to know what the dynamics of this special ecosystem are and how this is connected to the rest of Arctic ecosystem,” he said.

diatom

A diatom, one form of single celled, microscopic Arctic algae, as seen under a flourescence microscope. Photo: Kyle Kinzler

“We know the Arctic is changing very rapidly in terms of ice cover, duration of ice cover and extent of ice cover. One of the things we need to understand if we’re going to try to predict what will happen to the Arctic in the future is the ice ecosystem and its importance to the functioning of the entire Arctic,” Andy said.

Tomorrow, Thursday, we head out onto the ice to sample. This afternoon I received my land use permit from the Ukpeaġvik Iñupiat Corporation, the organization that owns the land we’ll be working on, and successfully completed my snowmobile training, so I’m officially ready for fieldwork.

For more information on this project, visit http://lifeintheice.wordpress.com or follow Lamont-Doherty Earth Observatory and the hashtag #LDEOarctic on Twitter.

Investigating Life in Arctic Sea Ice

Arctic Sea Ice Ecology - Tue, 05/14/2013 - 14:08

Andy Juhl and Craig Aumack, microbiologists from Columbia University’s Lamont-Doherty Earth Observatory, are spending a month in Barrow, Alaska studying algae in and below sea ice, and how our warming climate may impact these important organisms. They’re investigating the factors that control the growth of algae inside of sea ice, how these algal communities are connected to other Arctic marine organisms and what happens to the organic matter that builds up inside sea ice. I’ve joined them to document and tell stories about their research, how it’s done, why and what they’re learning.

Barrow, Alaska

Barrow, Alaska

Barrow is the northernmost point in the United States and is situated where the Chukchi Sea meets the Beaufort Sea. Throughout the long winter, these waters are covered with a thick layer of ice. This ice is home to many different microscopic algae, which form the base of the polar food web.

During late winter and spring, large communities of these algae flourish, or bloom, inside and on the undersurface of the sea ice. As the ice melts, algae are released into the nutrient rich waters, feeding plankton and higher trophic levels, including fish, whales and seals.

The Arctic is warming faster than any other place on the planet, shortening winter and causing pack ice to thin and break up earlier and earlier each year. How will these changes impact the Arctic marine food web? Answering this question and understanding how the ice algae respond to our warming climate will inform resource managers and policymakers, as well as local residents, of how the larger Arctic marine ecosystem may be impacted.

Andy and Craig hope to learn how our fast-warming climate and the resulting dissipation of sea ice affect the entire marine food web. This knowledge is essential to assessing the value of the ice community in the Arctic and is paramount to predicting ecosystem-wide consequences to rapidly changing Arctic environments.

We’re based at the UMIAQ field station in Barrow, which provides logistics support for NSF-funded scientists conducting research in the area. From Barrow, we’ll travel across the sea ice by snowmobile to nearby Point Barrow, where we’ll establish sampling stations and drill and remove cores of ice. Samples will be analyzed back in the lab to investigate the flux of the algal organisms and organic matter from the sea ice to the water column during the spring melt.

Over the next few weeks we’ll share stories from the ice about our research, the role sea ice algae play in Arctic ecosystems and how that’s changing, and what’s it’s like to live at the top of the planet. And, if we’re lucky, a few pictures of whales and polar bears.

Building the Team

Peering Through Polar Ice - Tue, 05/14/2013 - 10:59
The Ice pod team in Kangerlussuaq, Greenland including science, engineering and NYANG members.

The Icepod team in Kangerlussuaq, Greenland including science, engineering and New York Air National Guard members.

The Lamont IcePod team is a blended mix of engineers and scientists learning from each other through the design and testing of this new instrument. With a range of talents and backgrounds, the project mixes seasoned field workers with those new to field work; experienced instrument developers with those newly learning this end of engineering; and scientists with countless hours spent pouring over Greenland ice sheet data with those exploring the ice sheet for the first time. It is the opportunity for mentoring and development that comes from this mix of early career with experienced personnel that has made the IcePod Instrument Development Project a good fit for its American Recovery and Reinvestment Act funding.

Chris Bertinato trained as an aerospace engineer before coming to Icepod.

Engineer Chris Bertinato communicates with the flight crew while he monitors the Lidar at the equipment rack during calibration flights. Photo: R. Bell

The Lidar track of flight elevation collected during the GPS calibration.  The different colors represent changes in the surface elevation. The small black 'bites' in the track are where water blocks the return.

The Lidar track collected during the instrument calibration. The different colors represent changes in the reflectance which when matched to the GPS provide surface elevation. The small black “bites” in the track are where water blocks the return. The airstrip is the rectangular patch in the center.

So who makes up the IcePod engineering and science team?  As we work through data and examine the products collected in the first part of our field season there is an opportunity to introduce members of the team and the data and instruments they operate.

Chris Bertinato trained as an aerospace engineer before joining the IcePod team. In the air he is the team’s connection to the flight decisions made by the crew.  Like the members of the flight crew he dons a headset as soon as aircraft begins its warm up. The headsets are connected into the plane electronics through lengthy cabling that trails behind each set. The cabling necessitates a threading and weaving between the crew as they move about the aircraft, testing and checking equipment and switches. Watching them work one can imagine a class devoted to practicing safe maneuvering about the plane while tethered to the electronics system – something like a Maypole dance!

A graphic demonstrates  pitch, roll and yaw on an aircraft. (from Media Commons)

A graphic demonstrates pitch, roll and yaw on an aircraft. Image: Media Commons

Chris is a main operator of the equipment rack and has responsibility for the Laser Imaging Detection And Ranging (LIDAR) system part of the optical package in the pod taking constant  measurements to find the surface elevation, and the inertial navigation system (INS) used to locate or “georeference” the data. The INS is a critical navigation aid that employs several accelerometers (motion sensors) and gyroscopes (rotations sensors) to continuously calculate the position, orientation, direction and speed of the plane as it moves through space.  INS were first developed for rockets,  but have become essential instruments for collecting referenced data in an aircraft, since the pitch, roll and yaw of the plane (see drawing) as it moves through the air can make it difficult to correctly locate and orient the data for processing. For those of us used to flying on commercial airliners, movies and music can provide enough of a distraction that we don’t notice the regular rolling of the aircraft as it responds to buffeting by the air around it.

The INS sits atop the cylindrical laser set up.

The INS is the square box sitting atop the  laser set up. Photo: R. Bell

The cylindrical housing for the laser sits snugly in one of the pod bays with the INS sitting atop in the small grey box.  The laser focuses down through a clear panel, and scans back and forth in a swath that at 3000 ft. of altitude swings approximately 3000 ft. wide collecting elevation information. The data is then fed through a processor that turns it into elevation data.

Lidar image over the airstrip.

Lidar reflectance image collected over the airstrip. IcePod data

The image above shows a swath of laser data over the airbase, and can be used to help explain the instrument.  The color in the image shows the reflectance of different surfaces to the laser. You will see three of the LC130 aircraft lined up across the front of the airfield, cleaned from snow and clearly outlined in the data.  There are two additional aircraft positioned in the middle of the image that are still surrounded by snow and therefore remain somewhat obscured. Trees, roads and other features in the adjacent area are clearly imaged.

Lidar image of a Greenland meltwater channel shown etched through the landscape. (Icepod image)

Lidar image of a refrozen Greenland meltwater channel shown etched through the landscape. IcePod image

In Greenland Lidar will be used to assist with locating features of interest in the ice sheet. The image above of meltwater channels in Greenland will be important to track during the summer season as these channels can reactivate seasonally, becoming a blue stripe on the otherwise white landscape. These darkened blue sections will absorb more heat energy from the sun due to their altered reflectivity (albedo) encouraging additional surface melt.  In an upcoming post we will discuss how the infrared camera carried in the pod will allow us to track the heat energy in the channel both in its current state, and as it begins to melt later in the season.

Meltwater Channels on the surface of the Greenland Ice Sheet show how the color can darken absorbing heat energy. (Image P. Spector)

Meltwater Channels on the surface of the Greenland ice sheet show how the color can darken absorbing heat energy. Photo: P. Spector

Lidar will also be used to detect openings in the ice sheet (crevasses). Many of the crevasses are deep yet not wide, making them difficult to detect without the assistance of instruments. Detecting crevasses is important as they pose danger for pilots attempting to land and deliver support to ground crews, can be deadly for overland traverses that are carry scientists and support staff across the ice,  and can provide us with critical information on changes in the ice sheet. Lidar data collected in our IcePod flights can be used to help in all of these situations.

For more on the IcePod project: http://www.ldeo.columbia.edu/icepod

Out of the Woods

The Broadleaf Papers - Mon, 05/06/2013 - 19:38

By Ana Camila Gonzalez

When we walked into the Sheraton in Springfield, Massachusetts we were greeted by none other than a wall full of cross sections from trees perfectly sanded to reveal the rings.

No way” I say. “I forgot the camera!” says Neil.

We were just walking into the Northeast Natural History Conference, along with Dario and Jackie from the Tree Ring Lab. When I pictured my freshman year of college last summer, I pictured a lot of things. I did not picture getting to go to a conference to present a poster on my own research.

On the first day we listened to talks given by people who dealt with everything from conservation science to birds and berries and beetles. I’ve gone to multiple talks at Lamont, but those talks are mostly geared towards graduate students, so I’m always the slightest bit lost listening to them. This conference seemed to be geared towards a wider audience: I could actually understand the talks. I couldn’t believe it at first. After the first day I knew a little more about a wide range of topics: I can now tell you about the reproductive cycle of a lobster, what kind of fruits allow birds to fly farther during migration and even the life cycle of an Emerald Ash Borer in a tree.

I also learned more about the research process, since many people were presenting research projects that we weren’t already familiar with. I thought there was only a specific set of proxies for climate, but I found that people are continually finding more and more. I listened as someone described how they were using a mountainside as a proxy for climate change, and I realized that one of the great things about environmental science is that you can use the world as your lab, in many cases literally.

That afternoon during lunch we were told to make sure our GPS systems were safely hidden in our car. We were warned that we had to realize that we were now in a “big city.” We joked at our table—all being from New York—about how Springfield didn’t seem like a big city at all. I liked the thought, however, of a field of science where so many people are able to work in small rural towns that they do see Springfield as a big city. Want to know a secret? As much as I like school in the Big Apple, and I see myself living the city life for a while after school, I don’t see myself living anywhere with a population over five thousand after that.

Everyone in the lab was scheduled to present the next day. I was scheduled to give a poster, but Jackie, a Senior undergrad at Columbia, was scheduled to give a talk: we were both freaking out in the hotel room that night, but she probably had more justification. That night Jackie, Neil and Dario went through their talks while I made a big deal over how to cut my poster. Jackie ended up cutting it for me; my hands were too shaky. I must have asked a million questions to prepare that no one ever actually asked me, but by the end of that night I felt ready. “At least I’m not giving a talk!” That didn’t really calm Jackie’s nerves.

The next morning we had an awesome breakfast, I bought a piece of flan for no apparent reason, and we headed to the conference. I set up my poster and less than a half hour later sat to watch Jackie, Dario and Neil give their talks back to back. They were all wonderful, and some questions were asked that sparked some good conversation. Someone made a comment about baldcypress, and my ears turned up at the corners. She was mentioning how incredibly sensitive it was to drought, and I have to admit I got a little too excited. I talked to her afterwards: “That makes so much sense! I’ve been trying to cross-date this batch of baldcypress for so long, and it seems like every drought year thus far has produced either a narrow, missing or micro ring, and yeah, like you mentioned, isn’t it crazy that they’re so sensitive…” yeah, I was a little over-excited. It worked out well, because I had to go stand by my poster directly afterwards.

 

 N. Pederson

Ana paying great attention to her inquisitor. Photo: N. Pederson.

 

This is it. I’m standing by my poster. Someone comes up to me. THEY’RE GOING TO ASK ME SOMETHING I CAN’T ANSWER… THEY’RE GOING TO… Hey, so can you tell me a bit about what you did?

Wait. Really? I can do that!

The rest of the poster session went well. I was asked more than “can you tell me about your poster,” but it wasn’t half as bad as I had imagined. There were many questions I could answer, and there were many that I couldn’t. I ended up liking the questions I couldn’t answer more, however, because they told me what to do next. The same scientist who I had talked to previously about the baldcypress caught me off guard when she told me she’d look forward to reading about my findings in a paper. I hadn’t thought about it before, but I guess that’s my next step: take the unanswerables and answer them.

All in all, I learned more than I ever thought I could at the North East Natural History Conference, and walked away with much more than just natural history.  I’m more excited than ever for what’s to come.

 

 N. Pederson.

Dario, fully coming out of the woods at the Northeast Natural History Conference. Photo: N. Pederson.

 

__________________

 

Ana Camila Gonzalez is finally out of the woods. She has, essentially, completed her first-year as a student in environmental science and creative writing at the Tree Ring Laboratory of Columbia University and Lamont-Doherty Earth Observatory. She has completed her blogging on the process of tree-ring analysis, from field work to scientific presentations…for now. We are happy to announce that she will be working with us for Summer 2013.

Until We Get It Right

Peering Through Polar Ice - Sun, 04/28/2013 - 21:13
Setting up a flight plan for the day. (Image M. Turrin)

Setting up a flight plan for the day. Photo: M. Turrin

When we left Stratton Air Field almost two weeks ago, I recall smiling when a mechanical issue temporarily pulled us from the aircraft and the woman shepherding us back into the waiting area remarked, “Don’t worry, we keep doing it until we get it right!” Today we are faced with just that type of day.  Testing a new system is all about running through the same set of operations until you get it right.”  For our team, this means flying the same patterns over the same locations looking for repeat targets to test and retest our instruments. 

Kirsty Tinto, LDEO and Major Steve Slosek, NYANG review the flight plans (Image M. Turrin)

Kirsty Tinto, LDEO and Major Steve Slosek, NYANG, review the flight plans Photo: M. Turrin

The aircrew arrives each morning ready to fly the patterns and routes we have selected. They are willing to redirect if the weather changes, or if our priorities shift, but we have stayed fairly consistent in our requests. Of course, being in Greenland, we talk about varying our plan and picking some of our science team’s favorite targets. It seems almost unfair to be here and not venture off to the fast changing Jakobshavn or Petermann glaciers. But we are a disciplined group with a specific mission…we need to do it “until we get it right.” The navigator programs the plans into his system and we are ready to fly.

 

 

Sondrestrom Fjord is always breathtaking and provides a steady supply of floating ice against a warmer liquid background for testing our Infrared camera (Image M. Turrin)

Sondrestrom Fjord is always breathtaking and provides a steady supply of floating ice against a warmer background for testing our Infrared camera. Photo: M. Turrin

We are lucky.  No matter how many times we fly over the Sondrestrom Fjord, it always looks stunning: the water a deep blue, the ice pieces feathered along the edge where the floating tongue ends. Once we move over the deeper ice in the center of the glacier, we still marvel at the twisting, refrozen meltwater streams that wind across the ice face.

Quick moving ice collapses along the edges of a lake forming crevasses and ridges. (Image M. Turrin)

Quick moving ice collapses along the edges of a lake, forming crevasses and ridges. Photo: M. Turrin

Over the rocky edges of the landmass it is still fascinating to see the twisting rolls of collapsing ice that pile and swirl along the brim of the flat-topped frozen lakes.  The mountains themselves look like painted rocks with their smooth and shiny surfaces.

It is hard to believe one could ever tire of these flights. Each area we fly over is more stunning than the next. Today our flight is cut short. Engine trouble brings us back to the base, but we’re hoping that tomorrow we’ll be back up in the air trying one more time, “until we get it right.”

For more on this project: http://www.ldeo.columbia.edu

Weaving the Data Strands Together

Peering Through Polar Ice - Fri, 04/26/2013 - 20:42
Full moon rising over Kangerlussuag at the start of the April 26th Holiday. (Image M. Turrin)

Full moon rising over Kangerlussuag at the start of the April 26th Holiday. (Photo: M. Turrin)

Holidays vary around the world with their dates and traditions, so it should have come as no surprise that we would find a holiday in our scheduled Greenland visit. Today, April 26, is “Store Bededag,” which translates as “Great Prayer Day,” brought by the Danish to Greenland when they ventured to this island from their homeland. Kangerlussuaq, and other populated areas of Greenland, are a mix of Danish and Greenlandic in people, language, food and tradition. The holiday does not stop our survey flights today, but a snow storm with low-visibility has brought us to the ground. In the end it is a good day to focus on data.

Prior to today we have completed several flights, each with a tightly designed purpose, and there is plenty of data to be gone through. With our newly designed system, each instrument must be tested individually for operational capability and range, and then assessed for the enhancement that comes from aligning the results with the data from the other instrumentation. Calibration runs are also required for some of the instruments. In the end, each flight ends with a stack of data disks which need to be reviewed in detail.

The start of the Sanderstrom Fjord ice tongue (Image M. Turrin)

The Sondrestrom Fjord ice tongue is a target area for the cameras on this Icepod flight. (Photo: M. Turrin)

Each flight has a list of priorities designed around specific target locations and weather availability. Yesterday our target instruments were the visible and infrared cameras, the laser system and the deep ice radar system. For the two cameras we would fly down Sondrestrom Fjord building a set of matching images.

Bobcat camera showing where fast moving ice has compressed into tight ridges. (Image R. Bell)

Bobcat camera image showing where fast moving ice has compressed into tight crumpled ridges. (Photo: R. Bell)

The Bobcat, our visible image camera, showed a wide swath of surface imagery, noting where fast moving ice had crumpled into bands of ridges, as well as where it had thinned, cracked, and showed evidence of refrozen melt water streams.

The Infrared Camera operates at a higher frame capture than the Bobcat, and collects temperature differences from the places where the ice has thinned or opened. The colder the surface, the blacker the infrared image; warmer surfaces show as white. The tongue of the fjord is an excellent testing area for this.

 

The infrared camera will collect temperature differences at the floating ice tongue. (Image M. Turrin)

The infrared camera will collect temperature differences where the floating ice tongue has broken into sections of floating ice that look like confetti strewn in the water. (Photo: M. Turrin)

The Deep Ice Radar was being fine-tuned on this flight. Following the first Greenland test flight, the system was adjusted and the team was anxious to see the results. We headed up Russell Glacier to get to enough ice depth to receive the radar returns, but with the weather worsening and the winds kicking up, we didn’t go any further than needed.

Steep faced cliffs are carved by glacial ice. Ice stretched down this rock face in thin ribbons. (Image M. Turrin)

Steep faced Greenlandic cliffs are carved by glacial ice. Ice ribbons stretch down this rock face, carving deeper ridges that may some day be waterfalls. In order to get to the deeper ice, we needed to fly away from the mountain ring that circles Greenland like a pointed crown. (Photo: M. Turrin)

 

LIDAR calibrations (shown in the monitor) can be like riding a roller coaster - some love it and some don't! (Image M. Turrin

LIDAR calibrations (shown in the monitor) can be like riding a roller coaster – some love it and some don’t! (Photo: M. Turrin

The LIDAR (Laser Imaging Detection And Ranging) testing was our last test of the day. Designed to give us surface elevation, with repeat use it can show change in ice surface elevation over time. In order to show small change in ice elevation, a very tight accuracy is needed, on the order of 10 cms. The LIDAR calibration was designed as a gridded pattern of 4 by 4 lines flown at 170 knots of air speed. Calibration flights can be bumpy and twisty, as the plane will roll with the turns needed to create the pattern. The 20-knot headwinds cause some additional turbulence, but the full eight passes are completed before a return to the airfield.

For more on Icepod: http://www.ldeo.columbia.edu/icepod

An Ice Landing

Peering Through Polar Ice - Thu, 04/25/2013 - 06:18
up a GPS at Kangerlussuaq airstrip. L-R Nick Frearson, Margie Turrin, Kirsty Tinto, LDEO (Image R. Bell)

Setting up a GPS at Kangerlussuaq airstrip. L-R Nick Frearson, Margie Turrin, Kirsty Tinto, LDEO (Photo: R. Bell)

Half of the people lining the walls of the Kangerlussuaq International Science Support (KISS) building are waiting to go north to the top of the ice sheet at Summit Camp, and the other half are waiting to go east to the top of the ice sheet at Raven Camp. The science and support teams have been ready and waiting for several days now, hoping for a break in the weather up on the ice sheet.

Ice sheets are large enough that they can create their own weather. Large mountains of ice several miles thick, they stretch into higher elevations and gather the clouds around them. The sunny but cold weather (-21 to -9 degrees C) is a tease to the group ready each morning and waiting for clearance, day after day.

Kangerlussuaq, Greenland weather (credit weatherchannel.com)

Kangerlussuaq, Greenland weather (credit weatherchannel.com)

For the Icepod team the waiting is just as difficult. A series of flight options have been drafted, but with the target of getting equipment and teams out to the camps, our flights are shifted for the moment to “piggybacks” with other flight missions. Piggybacks are actually an excellent opportunity for the project to show how the pod might work once the full system is tested and ready for science use. The project design is for the pod to be fully integrated into the guard’s NSF Operation Deep Freeze mission of supporting science in the polar-regions. In the future, as the LC130’s deliver cargo and personnel to the polar science camps, the pod can be switched on by the loadmaster to gather data as the aircraft transits.

The NYANG delivering cargo to Raven Camp, Greenland (Image R. Bell)

The NYANG delivering cargo to Raven Camp, Greenland (Photo: R. Bell)

Word comes mid-morning that the first flight of carpenters and materials will head to Raven Camp.  There is not room for us but we are set for the second flight. The runway at Raven Camp is a groomed strip on the ice sheet, so the pod will make its first ice landing.

The first morning flight and ice landing go well for the pod, but one aircraft engine is causing some concern. The aircraft is looked over and the engine is cleared for us to take off late in the day with the second cargo delivery. We will fly out at high altitude before we stop at camp to install a temporary GPS for an Icepod GPS calibration. A forklift is used to load two large pallets of cargo onto the metal tracks that run the length of the aircraft and that assist the quick release of the supplies. The delivery at Raven Camp will be a “combat offload” with the cargo unstrapped and the plane moving forward on the ice so that the load slides out the back.The pod team is loaded and ready to head out.

Cargo Combat Offload

“Combat Offload at Camp Raven April 23, 2013 with the Icepod project. (credit Matt Patmore)”

 

Leaving the plane to set up the GPS (Image R. Bell)

Leaving the plane to set up the GPS (Photo: R. Bell)

With the cargo delivered, several of us exit the aircraft to install a GPS base station on the ice sheet so that the pod can complete its GPS calibration. A cloverleaf design will be flown with 20 to 30 degree turns closing the loops and straight lines between, while the GPS tracks the changes in direction and the movement in the air. In the pod design an array of GPS’s were mounted, one on the aircraft hatch and several on the pod itself, in order to determine the best location for “seeing” the satellites and yet be close to the instruments. The GPS is critical to all the data, used to tie back to a specific point on Earth. One station is set up back at Kangerlussuaq, and the second set up at Raven Camp will provide us a closure point so that we can tie together and adjust all the points in between.  

 

Nick Frearson and Kirsty Tinto of Lamont-Doherty set up the GPS base station in front of Dye 2, Raven Camp, Kangerlussuaq (Image M. Turrin)

Nick Frearson and Kirsty Tinto of Lamont-Doherty set up the GPS base station in front of Dye 2, Raven Camp, Kangerlussuaq (Photo: M. Turrin)

The station is set to operate. The team returns to the aircraft from the ice sheet and the calibration is flown. A follow-up flight to Raven Camp over the next few days will retrieve the GPS station. Once completed, the team heads for home over the ice sheet for a 9 p.m. touchdown. Although the aircraft loses an engine in the return transit, the day is determined a success with the completed piggyback flights, ice ramp landings and the GPS instrument calibration.

GPS installed in front of Dye 2, Raven Camp.(Image M. Turrin)

GPS installed in front of Dye 2, Raven Camp.(Photo: M. Turrin)

For More on Icepod: http://www.ldeo.columbia.edu/icepod

 

Raven Camp

Peering Through Polar Ice - Mon, 04/22/2013 - 17:31
Raven Hill, also known as Black Hill, rises above the town of Kangerlussuaq.

Raven Hill, also known as Black Hill, rises above the town of Kangerlussuaq, Greenland. (Image M. Turrin)

Ravens dominate the Kangerlussuaq landscape. Perhaps it is their deep ebony color and solid frame, or perhaps it is the white stillness of winter with little else but humans moving about, but whatever the cause the ravens are a recognized presence. The towering black hill rising above the glacially carved fjord is aptly named Raven Hill and boasts a steady circling of the mythical black winged creatures calling out in their raspy voices. With ravens being much a part of the region, it seems only fitting that our first flight would be to Raven Camp in search of deep enough ice to test the Deep Ice Radar system or “D-Ice” as it is referred to.

Flight planning (L-R) Kirsty Tinto, LDEO,  Maj. Josh Hicks, NYANG, Robin Bell, LDEO.

Flight planning (L-R) Kirsty Tinto, LDEO, Maj. Josh Hicks, NYANG, Robin Bell, LDEO. (Photo: M. Turrin)

The day starts out a bit hazy and the weather is forecast to deteriorate during the day. Most flights have been cancelled, but the Icepod team has been cleared for flight if we can manage a departure by noon and return to base by 2 p.m. Sensor and equipment adjustments keep the team busy until mid morning, and weather maps are continually being consulted for updates. Several times the planning team reconfigures the flight lines looking for the optimal plan to maximize the testing of the equipment with available time and weather considerations. Our NYANG partners are as anxious for the flight to go as the Icepod team, but if there are any weather concerns, caution must override enthusiasm. With the camp being at a higher elevation than Kangerlussuaq, the weather can vary considerably from the base.

The edge of the ice sheet is just visible flying towards Raven Camp in the south central section of Greenland.

The edge of the ice sheet comes into view through the misty haze as we fly toward Raven Camp in the south central section of Greenland. (Photo: M. Turrin)

Raven Camp lies at close to 2000 meters (~6800 ft.) elevation, where the glacial ice is approximately 1800 meters thick. “Noise” in the radar system drops after 1200-1500 meters of ice thickness, so although the weather is poor, we are hoping to get to this ice thickness to run a first real test of the D-Ice. Unlike our optical systems, the radar is not affected by poor visibility, so this is the right decision for the flight today. The plane is loaded with cold weather emergency gear, standard protocol when flying in the polar regions, and we take off down Sondrestrom fjord, making the noon flight departure time.

Kangerlussuaq lies at the mouth of the Sondrestrom Fjord in southwest Greenland.

Kangerlussuaq lies at the mouth of the Sondrestrom Fjord in southwest Greenland. (Photo: M. Turrin)

This series of flights is designed for instrument testing, so the science team is troubleshooting as they fly. Every instrument is tested in the short two-hour flight, and procedures are reviewed. The sound in the aircraft is deafening and earplugs are mandatory, which makes communicating challenging, but communicating is an essential part of the testing.

(L-R) Lamont's Scott Brown, Nick Frearson, Robin Bell discuss the camera function during flight.

(L-R) Lamont’s Scott Brown, Nick Frearson, Robin Bell huddle to discuss the camera function over the noise of the aircraft during flight. (Photo: M. Turrin)

The plane reached the edge of the deep ice and the aircraft lowers to a survey elevation of 900 meters (3000 ft.) above the surface flying along the ice contour. The radar system is up and recording. In too short a time, the plane has reached Raven Camp, but the poor weather conditions limit our ability to see the camp below. The aircraft turns and we head back to base. In our post-flight debrief, reviewing data takes a top priority for tomorrow. With a limited number of flight hours available, every flight is precious, so we need to be sure that assessment and adjustment is made to the instruments as we go.

For more on this program see: http://www.ldeo.columbia.edu/icepod

Greenland Welcomes Icepod and the 2013 Science Season

Peering Through Polar Ice - Sat, 04/20/2013 - 20:27
Greenland’s west coast is lined with ice-topped mountains reaching up to touch the clouds. (photo M. Turrin)

Greenland’s west coast is lined with ice-topped mountains reaching up to touch the clouds. (photo M. Turrin)

00 AM 'shuttle' to collect science teams and their baggage for the Greenland Science Season.

The New York Air National Guard runs a 5:00 AM ‘shuttle’ to collect science teams and their baggage for the Greenland Science Season. (photo M. Turrin)

Icepod joined the first large wave of science teams headed to Greenland via the NYANG LC130 transport system. Four LC130 aircraft were packed to bursting with pallets of equipment, supplies and science teams anxious to get to their designated research locations. Planes one and three were designated for cargo load, plane two would carry the bulk of the science personnel, including half the Icepod team, and plane four would carry Icepod with its skeletal engineering support team. 5:00 a.m. pick-ups for the science members set up the planes for staggered departures every 30 minutes starting at 8:00 a.m. With a flight time of seven hours from Schenectady NY to Kangerlussuaq Greenland, an early departure facilitates moving through customs and getting settled with the science support staff that awaits the group in Greenland.

LC130 Line Up prepares to head to Greenland with the IcePod visible in the front of the line. (Photo R. Bell)

LC130 line up in preparation to head to Greenland with the IcePod visible at the front of the line. (Photo R. Bell)

All the aircraft were packed from end to end with either cargo or personnel. While we waited for the pallets of cargo to be loaded onto the planes the science teams’ discussion focused on how Greenland’s ice will be dissected and examined in the upcoming season. One group will look at ice surface processes using ground penetrating radar and shallow ice cores starting at the Dye 2 location, another will drop into the high elevation Summit camp to start an overland traverse examining the ice (although we learned that nighttime temperatures are running at -50 degrees C, a bit too low currently for set up). A third group will examine the firn layer (that section in the ice that is just starting to compress) over Jakonbshavn glacier, and the Icepod team will be doing their first set of instrument test flights in polar conditions looking at the ice from the bed up to the ice surface.

Approaching Goose Bay to refuel. (Photo M. Turrin)

Approaching Goose Bay to refuel. (Photo M. Turrin)

The science personnel were finally loaded into Plane two, which had been divided across the middle of the main cabin, to accommodate cargo aft and science teams foreward packed knee to knee in two sets of facing rows.  With this heavy load the aircraft would need to stop to refuel in Goose Bay, in Labrador, Newfoundland, Canada. Goose Bay Air Base, affectionately known by many as “The Goose”, was once home to Strategic Air Command’s 95th Strategic Wing. The ice cream served to the visitors of the airfield has become part of the travel lore of the teams en route to Greenland, so by the time the wheels touched down, everyone’s thoughts had moved from polar ice to ice cream. Two baskets full of assorted Good Humor truck style ice cream were quickly dispensed and we were back up in the air and underway for the last half of the journey.

 

 

//www.strategic-air-command.com/bases/Goose_Bay_AFB.htm)

Goose Bay Air Base provides a refueling and emergency stopping location for aircraft, in fact a United aircraft was undergoing emergency repairs when we stopped through. (image from http://www.strategic-air-command.com/bases/Goose_Bay_AFB.htm)

When the west coast of Greenland came into view the sun was just peaking through the clouds lying low along the tops of the coastal mountains. The shadowy ridgeline just visible through the mist was a welcome sight after seven hours of flight.  Tomorrow will be a day of setting up base stations and reviewing some of the transit data, then the Icepod project will launch into its first set of Greenland test flights.

The west coast Greenland mountains tip through the clouds as the sun breaks along the ridgeline. (Photo M. Turrin)

The west coast Greenland mountains tip through the clouds as the sun breaks along the ridgeline. (Photo M. Turrin)

For more information on the IcePod project: http:www.ldeo.columbia.edu/icepod

Visual Skateboarding

The Broadleaf Papers - Fri, 04/05/2013 - 18:57

By Ana Camila Gonzalez

 

“You can do math on excel?” I ask. I immediately imagine a face-palm response, but Dario, one of my advisors, is nice enough to hide it. I’ve collected tree core samples, I’ve prepared them and cross-dated them. Now what?

Oh, right. The Science.

 N. Pederson

Science! Photo: N. Pederson

 

I guess I never really understood there could be so much involved in answering a question. When I imagine the scientific method I’ve learned since the sixth grade, I somehow imagine a question that can be answered with a yes or no. If I let go of this apple, will it fall to the ground? Hypothesis: yes, it will. Experiment: yes, it does. Conclusion: yes, it will. To the credit of my high school science teachers, it’s not that they didn’t make it perfectly clear that the why and the how are just as important as the yes or the no. I just couldn’t imagine that you’d have to explain why the apple falls with four different figures: haven’t you seen an apple fall too?

Dario is helping me understand how to analyze the data from the black oak samples I have already been working with for some time now. I know these samples. Or at least I think I know these samples. I’m learning there’s more to know about them than I initially thought.

We’re analyzing the climate response, which proves to be exactly what it sounds like. We have recorded measurements of climate (precipitation records, temperature records) and a proxy for tree growth (our ring width measurements!) and by comparing those we can see how a tree population responds to a range of climactic conditions. Alright. I can do this. I’ve made graphs before.

 

So we’re going to find correlations,” says Dario.

Click on an empty cell.” I start to make a scatter plot; I think what we’re going to do is look at the slope of a line of best fit.

So we’re going to see if the correlation is positive or negative?” I ask.

Yes, but we also have to see if the correlations are significant.” Isn’t any correlation higher than a zero significant? They’re showing a relationship. 

Dario continues, “Any correlation above a 0.2 or so is significant for the hundred years of ring width and climate that you have for this analysis.” I learn how to use the =correl function to compare the populations to temperature and I have to say I’m disappointed. I thought 0.2 sounded so low, but some of my data is showing a much lower correlation, and the data that is significant only ranges from about really close to 0.2 to 0.38 or so. I wanted to see a 0.5 correlation like I did between tree samples within a species as I was cross-dating. Comparing precipitation to ring width gives me slightly higher correlations, a few in the 0.3 range, but I’m still feeling underwhelmed.

No, but it’s still significant! It matters!” Dario tells me to make a scatter plot comparing precipitation to ring-width measurements over time at both sites. At first it looks like a ball of yarn, but as I mask the plot out I can see why those 0.3 correlations are significant. I follow each curve, visually skateboarding up and down the peaks and valleys and noticing that I’m going up and down a lot of very similar hills as I do so. What’s most rewarding is looking for years I know are drought years (1966 and 1954 were big droughts) and seeing relatively low measures of precipitation and ring width during those years. I knew while I was cross-dating that those years were important when I saw how small the rings were, but now I can prove it. Like the apple falling, I can’t just say that because I see the rings are small those were dry years. I have to compare it to precipitation records, temperature records, and, dare I say it, the Palmer Drought Severity Index (I have to admit I don’t entirely understand the mechanics behind the index, but I understand that dryness is a composite of precipitation and temperature forcings).

Dario, over multiple days, teaches me a few more nuances of Excel and helps me understand the ARSTAN program and how we use it to make our ring-width measurements more effective as proxies for tree growth. He mentions this would all be easier if I knew how to use R. I make a mental note: learning R is the next step. If I thought that was scary, now I have to put this information on a poster. That real people will see. At a real conference.

Neil shows me a few poster examples, and the message is clear. Show your data instead of describing it in words. That also means I’ll have to explain my data by actually… talking… about it. Gulp. The North East Natural History Conference is next weekend, but I feel like I’m ready. I understand the why and how after analyzing my data. At least I understand it enough to give an answer better than yes or no.

 

__________________

 

Ana Camila Gonzalez is a first-year environmental science and creative writing student at Columbia University at the Tree Ring Laboratory of Lamont-Doherty Earth Observatory. She will be blogging on the process of tree-ring analysis, from field work to scientific presentations.

I’ll Go on a Cross-Date if You Show Me Some Rings

The Broadleaf Papers - Thu, 03/28/2013 - 20:04

By Ana Camila Gonzalez

 

Ever since I’ve started learning to cross-date tree core samples, I’ve learned I have a type. I prefer my tree cores to be black oaks, middle-aged, with some nice big rings to show me. Alright, fine, I can deal with some smaller rings every now and then. As long as they’re some nice marker rings.

Unfortunately, the trees don’t seem to be trying to impress me.

 AC Gonzalez and N. Pederson

Sensitive black oak rings, showing the 1960s drought (faint bands of wood between the two dots on the right side of this image), from eastern NY State. Image: AC Gonzalez and N. Pederson

I was told on a fifth grade field trip that you could tell the age of a tree by chopping it down and counting from the ring on the outside, which represents the current year, to the inside ring, which represents the year it started to grow. I’m coming to learn at the Tree Ring Laboratory of Lamont-Doherty Earth Observatory that there are a few problems with that statement.

Primarily, you don’t have to chop the tree down. I learned while doing fieldwork that coring a tree does not damage it at all. More importantly however, you can’t always find the exact age of a tree by simply counting the rings backwards. One has to verify the years you assigned to each ring against other samples, and, occasionally, against known climatic or ecological events. Sometimes a ring can be missing, possibly from either a very dry year or insect defoliation that causes a lack of growth on the side of the tree you’re looking at. Sometimes a ring is there, but it’s tiny; so small you need a microscope to see it: a micro ring. And this is where cross dating comes in.

 N. Pederson

A large, Y-shaped black oak in eastern NY State. Photo: N. Pederson.

 

I sit down to cross date my first batch of samples, black oaks from 2003, with rings I can see without using a microscope. I use the microscope regardless, of course, because sometimes what looks like a ring from far away can actually be a false ring: an “extra” late wood growth caused by an early freeze, early warming, or some disruption to ‘normal’  seasonal weather. The microscope helps me see whether these bands have defined edges or seem to fade, and I’ll know that only the truly defined ones are rings.

I seem to be lucky, however, as none of the Black Oaks seem to have any false rings. I’m actually eager to find some missing rings and micro rings, but I don’t find any of those either; missing rings in oak are so rare that you’ll likely be able to plant your own oak forest and watch it grow to maturity before you find one. This is so easy, I think. I feel like I have it in the bag.

I finish measuring the rings on my samples and labeling them with the years I assigned hypothetically to each ring from my cross dating. Now I’m ready to run the measurements through COFECHA, a program that gives me the correlations between individual samples and finally the correlation between all of the samples. When I first run the program with every sample, I’m told something between 0.5 and 0.6 is the expected correlation for ‘good’ black oaks (in other words, there is a 50 to 60 percent chance that given the ring-width measurements on one sample, you’d be able to predict the measurements on a second sample from the same batch). I get a 0.3 correlation. What could I have possibly done wrong?

I soon find that although Black Oaks don’t usually produce missing rings, micro rings or false rings, it is still a possibility, for reasons I didn’t understand at that time. There is also the possibility of human error resulting from mounting the samples incorrectly, missing pieces of the sample after coring and so on. (Editor’s note: one of the biggest issues dating oaks is jumping from one side of a ray to another while moving down an increment core. Sometimes the rings that are aligned across this division are not!).

———

 

What I was doing up until this point was just writing down the years where I found narrow and wider rings as marker rings and trying to find a pattern with everything I wrote down. It was helpful, but I needed to learn more about cross dating to make a few problem samples correlate with the population.

First, I was told I could take a step back and get my nose off of the microscope. By holding up a problem sample to one with a good correlation, I could try and find where patterns aligned visually, and this was usually more helpful than just trying to find the patterns in a sea of numbers I had written down. Second, I was focusing too much on individual samples and not remembering that multiple cores are often taken from the same tree: before a sample can correlate well with an entire forest it is easier to make sure it correlates against the others from the same tree. Finally, I learned that some trees—the very young, the very old, and the trees that constantly get outcompeted for resources—just don’t conform: the rebels, the grumpy old men, the proud nerds. Very suppressed rings won’t correlate well with a series, and neither will very wide rings that signal a release from competition from neighboring giants.  Sometimes a 0.3 or a 0.4 correlation is the best you can get for a sample, and I had to learn how to know whether to accept that or keep trying further.

That first batch took me a week and a half to finally cross-date. You should’ve seen the look on my face when I saw my first correlation in the 0.5 range.

 

And that was just the black oak.

 

 N. Pederson

Two, twin black oak – velvet goodness! Photo: N. Pederson.

I decided to continue coming to the Tree Ring Lab over winter break, and at first it was incredibly peaceful. A few days of sanding and stabilizing some pines really put me in the Christmas spirit. And then I met Baldcypress, which made me more of a Grinch.

At first, baldcypress and I were really only going to be a one-time thing. I was only told to measure three or four batches from the 80s as a side project, but after I logged all the measurements the COFECHA results were cringe-worthy. I was told I had to try my hand at cross dating the cypress.

If I thought the black oak population had trouble samples, I reconsidered. While Quercus velutina hardly ever displays missing rings, false rings or micro rings, Taxodium distichum seems to want to flaunt them. My first batch had mostly been false rings, but I also learned what a micro ring actually looked like.

I remember staring at a set of what should have been ten rings for 20 minutes, but only seeing nine. I finally asked my advisor and then watched as Neil marked a band relatively darker than its surroundings a cell wide as a ring. If any ring could be called a marker ring, it was this one. Sometimes finding a micro ring where I knew, from the chronology, that a narrower ring should be, was actually a relief. 1966, a heavy drought year for most of the Northeastern US, quickly (and morbidly) became my favorite year.

I dealt with so many false rings that I felt like I was five and my fingers were all turning green (I’m glad no one ever showed me this; I always felt like a princess). Every time I thought a sample couldn’t have any more missing rings I found more. I started thinking everything was a micro ring.

The black oak took a week and a half. I’ve gotten through three batches of baldcypress, and I’m on my fourth: I started over winter break and it is currently spring break. Of course, I’ve been working on other things as well, including a poster presentation on my black oak samples for the Northeast Natural History Conference, but it feels as if the baldcypress just doesn’t want to leave me alone.

 

Yes, I do have a type. I like real rings, I like big rings and I like rings that conform. In the end, however, I’ve learned more from the “problem children” than the ones that worked out like I wanted them to. I might even admit that the baldcypress has been much more rewarding to work through.

Shhh, don’t tell the black oak.

________

 

Ana Camila Gonzalez is a first-year environmental science and creative writing student at Columbia University at the Tree Ring Laboratory of Lamont-Doherty Earth Observatory. She will be blogging on the process of tree-ring analysis, from field work to scientific presentations.

 

You must be choking

Tree Stories - Tue, 06/26/2012 - 08:54

Every year, when the height of the dry season comes to northern Thailand, the air gets foul. The extent of the problem is dependent upon, among many factors, the weather and more specifically the temperature profile of the air.  When a temperature inversion sets in, warm air aloft “caps” the cooler air that has descended into the valleys and prevents circulation (the normal state of the atmosphere is a lapse rate of decreasing temperature with altitude). As a result of an inversion, air pollution from cars, buses, burning, cooking, construction, etc., gets trapped in the valleys and basins and develops into an increasingly toxic brew. This doesn’t occur to extreme levels every year, but I have experienced it several times in Chiang Mai over the past decade, and this past season was pretty bad (see Thailand: pollution puts Chiang Mai off the tourist trail).

Photos of Chiangmai air pollution this past season: All pictures were taken at midday, no clouds, just smog.

The levels of fine particulates became very high, and this causes major respiratory problems for many people, the very young and very old in particular. But clearly it doesn’t do anybody any good. Because I am prone to bronchial infections, when the air got bad this year I suffered for weeks with a severe hacking cough that may have led to my herniated disk injury. In a wonderful twist of irony, I traveled to Bangkok, Saigon and Taipei to get cleaner air to help me overcome my illness. It worked too, but when I returned to Chiang Mai before my return home I began to deteriorate once again. (See my blog post, That Thousandth Cut, for the backstory.)

The costs of this problem are very high, due to major health problems for a large and poor population, and flight delays in the region due to poor visibility. Since it is a very specific set of conditions that leads to these inversion events, it would be important to explore the effects of regional temperature projections and how this might effect the occurrence and duration of future events. More importantly, are there ways to mitigate the effects of these inversions?  Obviously, producing less fine particulates and reducing the primary pollution sources is paramount, but for that there needs to be the will at the highest of levels, and since the overall problem knows no borders, there isn’t the will. Much of the blame each year goes to the hill tribes who burn the surrounding mountainsides, but it seems that much of the source is more localized than that, and much of it is regional pollution that sits over the entire region. Whatever the source, however, something needs to be done. The problem is that when the rains come the awful air is cleared out, and with it any sense of urgency to act. It is then forgotten about until the next inversion comes a year later.  This short-term memory does not help.

This from a Chiang Mai based website on the problem:

Air Pollution: Key facts from the World Health Organization

  • Air pollution is a major environmental risk to health and is estimated to cause approximately 2 million premature deaths worldwide per year
  • Exposure to air pollutants is largely beyond the control of individuals and requires action by public authorities at the national, regional and even international levels.
  • The WHO Air quality guidelines represent the most widely agreed and up-to-date assessment of health effects of air pollution, recommending targets for air quality at which the health risks are significantly reduced.
  • By reducing particulate matter (PM10) pollution from 70 to 20 micrograms per cubic metre, we can cut air quality related deaths by around 15%.
  • By reducing air pollution levels, we can help countries reduce the global burden of disease from respiratory infections, heart disease, and lung cancer.
  • The WHO guidelines provide interim targets for countries that still have very high levels of air pollution to encourage the gradual cutting down of emissions. These interim targets are: a maximum of three days a year with up to 150 micrograms of PM10 per cubic metre (for short term peaks of air pollution), and 70 micrograms per cubic metre for long term exposures to PM10.

More than half of the burden from air pollution on human health is borne by people in developing countries. In many cities, the average annual levels of PM10 (the main source of which is the burning of fossil fuels) exceed 70 micrograms per cubic metre.  The guidelines say that, to prevent ill health, those levels should be lower than 20 micrograms per cubic metre.

Chiang Mai isn’t the only place that suffers from temperature inversions that create health hazards, and in fact it is a common problem for much of the basin and range country in the western USA. My colleagues at Utah State University suffer through an annual period of very poor air that gets trapped along the Wasatch Range every winter (see  NOAA, National Weather Service Forecast Office, Salt Lake City, UT). Therefore I plan to avoid going to Logan in the dead of winter. Therefore I plan to avoid going to Logan in the dead of winter.

As bad as the problem is in Chiang Mai, it is even worse in other parts of Thailand, and across much of Southeast Asia. The link between anthropogenic pollution — inclusive of greenhouse gases — and a plethora of health issues ought to be at least as compelling a reason for us to cut emissions than the far more difficult to understand link to AGW (Anthropogenic Global Warming.)

As I have alluded to earlier, if people can see how these issues can impact them in more immediately pressing ways they are more likely to care about action. I always thought the AGW debate was too esoteric and too complicated to explain to a general population that is bombarded with too much information on a daily basis. Whereas the “hey, this stuff can kill you” message is one that just might get through. As for me, I plan to avoid these areas when the air gets like this, so my forays into Southeast Asia will try to avoid the February-March season, and for good measure April too because it is so bloody hot! I am lucky enough to have the freedom to choose my residence times. For most of Chiang Mai’s population they don’t have that luxury, and they just have to endure the best they can. In the meantime, if you travel to northern Thailand, Laos or Myanmar in February, you might want to bring your gas mask.

 

That thousandth cut

Tree Stories - Tue, 05/22/2012 - 08:13

PALISADES, NEW YORK — My hands floated above my head, rotating in all directions, swaying weakly like reeds rustling in a gentle breeze. At least that was the image I held in my head, clouded as it was by the anesthesia. Between my hands I saw Orawan at the foot of the bed, staring at me with great relief in her face.

“Hey baby, how are you?” I asked almost a little too cheerfully, as I dropped my arms to the bed. ”Come here, give me a hug.” I was seriously groggy, and it was difficult to stay awake. I have memories of an alarm going off next to my head and a nurse urging me to breathe, happening more than once. I am not sure if that really happened or if it was imagined, but my memories from those few hours are hazy.

“Hey, go easy there.” Orawan chided as she took my hand. ”Try not to move too much.” I could sense the massive relief she was feeling, after waiting nearly 4 hours to see me after I left her standing in the hallway as they wheeled me into the theater.

The surgery was a success, or so I was informed. At least I could still move my arms, and I didn’t see a respirator anywhere in sight. I quickly checked for a colostomy bag and was relieved not to find one. I was still dopey enough that I couldn’t feel any pain yet (that would come in time), and the intense pain I had lived with for the past five weeks appeared to be gone, as the bits of ruptured disk had been removed from my spine, relieving the pressure on my C7 nerve head.

So, what happened? The week before I returned from Asia, on March 12, I awoke with a burning agony running down my left arm that would not desist. I didn’t know the extent of my injury until I had gotten home to New York and had an MRI, after a week of unrelenting pain in my left arm and under my scapula. It was a very uncomfortable flight across the Pacific back to New York, made tolerable only because of a class upgrade and lots and lots of drugs.

The MRI showed that I had clearly ruptured the disk between my C6 and C7 vertebrae, and surgery was pretty much the only option. Though I don’t remember it, I had told Dr. Quest that I loved him, emphasizing that it was not in any manner that should elicit his alarm, but love just the same. He took care of me as promised, and now that it was over I felt a massive sense of relief. Now, six weeks after surgery I am mostly recovered, with only minor pains and numbness as reminders of those terrible 5 weeks.

So what has this to do with climate change? Well it is the reason for my absence from this blog, since I couldn’t sit at my desk for more than 20 minutes at a time, and the reason for me barely accomplishing any work for more than a month. And now that I am recovering, I face a mountain of work the likes of which I have never seen, but never have I been so thankful for being able to work.

It had surely been a run of bad luck since my last entry, starting with the infection in my scalp from hitting that doorjamb in Chiang Mai, an infection that was not even cured when I developed a terrible bronchitis from the smoke and haze of Chiang Mai’s annual February foul air festival (a phenomenon that is related to climate change). After my return from Yunnan I went to Taipei for a week of lectures and meetings, and Taipei’s far cleaner air began healing my lungs, but I was still with a very deep cough that would often wrench me from sleep. I then went to Vietnam for a week for the opening of the International Center for Tropical Highlands Ecosystems Research, with even cleaner air in Dalat, and that just about finished off the bronchitis. But scarcely two days back in Chiang Mai, back in the horrible air, and I began to cough once again. It was then, on Monday the 12th of March that I awoke in such pain. The doctors believe that it may have been the pressure from coughing that served as the final straw in rupturing my disk, but in truth the injury was probably the result of a lifetime of accumulated injuries and strains, football, hockey, basketball, coring trees and carrying a backpack. It could have been any and all of those things.

So, I am back now, ready to catch up on a few entries I have wanted to write. I apologize to Lori for the long delay and I hope she can forgive me, and welcome me back. The way I see it things can only go up from here, now that Dr. Quest delivered that thousandth cut.

A thousand cuts

Tree Stories - Thu, 02/02/2012 - 20:15

CHIANG MAI, THAILAND — The expression “death by a thousand cuts” refers to the practice in imperial China of killing someone by slicing them repeatedly, never very deep, until they die from their multiple, tiny wounds. I thought of this on Friday night when I hit my head on a door jam, cutting my scalp on the rock-solid, wooden edge. This happens to me frequently over here, since I am about 188 cm tall and the bathroom doors are always about 185 cm maximum. Just low enough that if I walk through upright I get a nice laceration on the top of my increasingly sparsely covered pate. I am pretty used to this by now, so aside from a momentary barrage of cursing, I didn’t think much more about it for the rest of the evening. However, the next morning, I awoke with a pain behind both ears and a bizarrely misshapen, triple-horned crest on the top of my head that was hot to the touch. Infection had occurred in about 5 hours. I went to Suan Dok Hospital the next day and the doctor said, “Yep, you have an abscess on your scalp, and the pain behind your ears is the swollen lymph nodes that drain the scalp.” He prescribed antibiotics and some wound dressings and told me to come see him next Saturday. After 3 days of medicine the infection is gone, and the swelling is down.

I have always heard how one needs to keep one’s wounds thoroughly cleansed in the tropics to stave off infection and sepsis, but I spend so much time here that I have gotten careless. I am reckless and clumsy, and I have had multiple wounds from a variety of things, and none has gotten infected to this stage. And it happened so rapidly that I was taken by surprise.  Death by a thousand cuts.

I leave for Xishuangbanna in southern China on Sunday. I am going there to lecture at the Xishuangbanna Tropical Botanic Garden hosted by my colleague Dr. Fan Zexin. Fan was one of the participants at the PAGES Asia2k workshop we just held in Chiang Mai, having been a contributor of tree ring data from the upper reaches of the Mekong River in Yunnan province. We are planning a collaborative project on studying the rare and endangered conifer Taiwania cryptomerioides that can still be found in some isolated stands. These trees are quite huge and can attain great age, but have been seldom studied for tree ring analyses and have the potential for great value in the upper Mekong. They are also being cut at an alarming rate everywhere they are found, so we are on somewhat of a salvage mission. If we are to get into the areas of Yunnan where the trees are found, it might have to be in late August after the winter cold and the worst of the monsoon rains.

One thing about developing tree ring reconstructions of streamflow, it has been shown that temperature from the upper headwaters regions can be as important a factor as rainfall for predicting baseline streamflow because of the importance of meltwater in keeping up base flow (i.e., flow in the dry season in the case of the Mekong, rather than the sizeable contribution of the annual monsoon rainfall that contributes to peak flow). This work is part of the overall goals of my Greater Mekong Basin project, and will give us the very important record of how the Mekong streamflow may have varied back in key periods of the past millennia. I will send an update from Xishuangbanna when I am there, and try to include some good pictures of the place. I have never been there so I don’t know what to expect.

It has been pointed out to me more than once that I have a tendency to talk about food a lot in my blogs. With this in mind, I will be sure to report on the great meals I am bound to have in Yunnan, and send some pictures as well.

 

My dinner with Usama

Tree Stories - Sun, 01/29/2012 - 14:03
The PAGES Asia2k Workshop participants

The PAGES Asia2k Workshop participants at EFEO, Chiang Mai.

CHIANG MAI, THAILAND — There was one table available, just being vacated, and Orawan and I hurried to grab it. The place was filled with foreign visitors — Australians, Israelis, Americans and Dutch — and they were talking loudly, drinking beer and wine, clinking forks and spoons noisily on plates filled with hummus, tabouleh and falafel. We fought our way through the tight crowd and made it to the table before the previous diners plates had been cleared. Andrew and Piyawit were both running late. This was it, the very end of the PAGES Asia2k workshop for us, and Andrew was the last participant to leave Chiang Mai. It was an exhausting week for us, and now it was over, the dust beginning to settle on a meeting whose objectives were not entirely met. In the midst of the noise and confusion a hand touched my shoulder and I turned to see the owner of Jerusalem Falafel, Zahavit, with a perplexed look on her face.

“What are you trying to do to me?” she said, looking serious. I realized I was smiling at her, in anticipation of our usually warm greeting, so I quickly sobered my expression to match hers.

“Im sorry?” I said. I had no idea what she was talking about. I watched as Orawan secured our table and then I turned to face Zahavit and give her my full attention.

“Why did you bring an Afghani into my restaurant the other night?” she was clearly distraught. “Didn’t you read the news this week? In Bangkok they arrested Al Qaeda members sneaking explosives into Thailand and some of them got away. I nearly had a heart attack when I saw him, but then I realized he was with you.”

“Oh, you mean Usama!” I blurted out, and quickly realized that saying his name likely didn’t help matters. “He’s not Afghan, he’s Pakistani.”I offered, perhaps helping even less. “He’s a great kid, a PhD student from Karachi studying with a colleague of mine. Really, he is a very sweet young man, and very bright.”

“I know now he is okay.” She said, more relaxed. “But at the time I nearly fainted. You should have told me you were bringing him when you made the reservation!” She scolded, and slapped my shoulder lightly to emphasize her concern.

The truth is, it never occurred to me that Zahavit, an Israeli expat living in Thailand, married to a local Chiang Mai man, and running this hugely popular restaurant since 1991, might be alarmed at my bringing Usama to her restaurant. I hadn’t seen any news all week, as I had been too busy with the workshop, but I also hadn’t planned to invite people to dinner here until the end of the day, choosing to come here primarily because we had three vegetarians in tow, and the food has never disappointed us. Zahavit and her husband, Chiang, are very friendly and most gracious, their food is excellent and it is one of my very favorite restaurants in Chiang Mai. Funny enough, when I asked Usama to join us, it occurred to me to ask if it bothered him that the place was Israeli. He looked at me, puzzled, and replied, “If the food is good and it is vegetarian, why would I mind?” Fair enough, I thought, and that was the end of it. But I can only imagine the alarm felt by Zahavit, at the sight of a young Pakistani man, decked out in full local garb and sporting the thickest black beard I have ever seen, walk into her restaurant and take a seat. It has apparently never happened before.

**********************

Usama and I

Usama and I take a coffee break.

“Usama Zafer Muhammed” I read his name out loud from the workshop participant list. He had joined me on the long teakwood bench outside of the conference room at the Ecole Francaise D’Extreme Orient, the beautiful location along the banks of the River Ping that was hosting our workshop (EFEO). It was during a coffee break, and Usama and I had been discussing the software I had just demonstrated that allows us to create point-by-point regression (PPR) reconstructions of climate from tree rings (while the folks who developed it were busy in another room attempting to reconstruct temperature over Asia — more on that in a minute), or other proxy sources that can be calibrated with climate data.

“Well, your name will almost surely cause you to be delayed at U.S. customs, but other than that I don’t believe you would have any problems”. Usama had asked me, with real concern on his face, if he would be in danger if he came to visit the U.S. The question really threw me, because as Americans we don’t think of our country as being unsafe to others, but it goes without saying that we all think of Pakistan as being a certain death for us to visit. Usama is a devout Muslim, and several times during the workshop he would go into a separate room to pray before returning to our group. He had told me earlier, when talking about sampling in the remote mountains of his country, that even he wasn’t safe in some areas because his religious and political views were far too moderate. However, he added, that if I were to travel with him to some of the areas where he is known, that I too would be safe, and in these other areas, we would both be in danger. I thought about it and realized that there are places in America that I don’t feel safe either, and places where I am pretty certain he might be hassled for being a Muslim. We surely have our share of violence and bigotry in America, though it is a very small minority that would engage in such behavior. Usama was making the point that it was the same in Pakistan, though the constant war and instability in that region, coupled with poverty and lack of real education for many, certainly exacerbate things.

In 2007 I had cancelled my trip to visit Usamas research institute in Karachi due to an attack at the airport in the hour before my plane was to leave Bangkok. Just as we were queuing at the gate, an announcement was made that the flight had been cancelled and they were putting us up at the Novotel for the night. In the ensuing confusion and while we all milled around at the gate the story came out that it was an act of terrorism in Karachi that was responsible for our cancellation. Early reports told of more than 40 people killed, and that the Karachi airport was unsafe. They would put us up for the night and see how things looked in the morning. Among the people on this flight were several Pakistanis, a few Australians, and one American marine on the security team at the Consulate in Karachi, and I had time to talk with many of them. The Pakistanis were all very sad to hear the news of the flight cancellation, and seemed distraught that I was now leaning toward not going. They seemed intent on convincing me that it was not as unsafe as I was hearing and that I should really go. I was headed there at the request of my colleague, Dr. Moinuddin Ahmed, to help him conduct a dendrochronology symposium and training session that was going to introduce tree ring analyses into their University system for the first time. It seemed quite exciting at the time I agreed, but now it seemed a little too exciting. I called Orawan from the airport and as soon as I told her what was happening she said, “I really don’t think you should go. Is it really worth the risk? I would feel better if you came back to Chiang Mai.” As far as I was concerned that was the last word, but I still was tempted to go until the marine took me aside, out of earshot of the others.

“How important is it for you to be in Karachi for this meeting?” he asked.

“Well, I promised my colleague that I would be there, I really ought to try.”

“Listen, you should know that the U.S. considers Karachi to be the most dangerous city for Americans in Asia, less safe even than Kabul and Baghdad. Dude, there is no green zone there and the Consulate is far from the airport. There’s nothing we can do for you if you get into trouble, so unless you absolutely have to go, I wouldn’t.” That was all he said, and that was all I needed to hear. The next morning they had resumed the flight to Karachi as the situation had stabilized, but I was on the first plane to Chiang Mai, to the great relief of my wife.

**********************

Paul Krusic, from Sweden, speaking with Usama

Paul Krusic, from Sweden, speaking with Usama at the workshop.

Usama presented his tree ring records from the high mountains of Pakistan, collected and processed over the past several years with Dr. Ahmed and other colleagues (see 500 years of Indus River flow modeling with tree rings), and he was here in Chiang Mai because he was among several other Asian researchers who were contributing their data to the overall PAGES Asia2k initiative that is charged with developing temperature reconstructions from Asia that ideally will cover the past 2 thousand years (hence, Asia2k). There are 2k initiatives for North and South America, Europe, Africa, Australia and even the Oceans. In all cases there are challenges of many kinds in producing the desired product (i.e., annual temperature — which will be used for the next AR5 model runs for the next IPCC assessment), but for Africa and Asia there are certainly greater obstacles than for other regions. Many of these difficulties are related to the fact that multiple, and often unstable, political entities comprise these continents, while many others are related to the culture of science in many of these countries where data sharing is simply not the norm. But one of the biggest obstacles is really that the proxy data are mostly precipitation sensitive more than they are temperature sensitive. As I have said previously, I believe that temperature (i.e., AGW related temperature) is only important because of its effects on the distribution of water on the planet, and it seems far more important to me that we understand the variability in precipitation around the globe, and to figure out how this might change in the future.

dr edward cook

Dr. Edward Cook addressing the workshop.

The director of my laboratory, Dr. Edward Cook, and I are both on the Asia2k committee, and at a meeting in Nagoya 2 years ago we worried how far behind our group was compared to others from the Americas, Australia and Europe, with regard to getting the necessary data from the research community. It was then that we hatched the idea (mainly it was Dr. Olga Solominas idea, and a great idea at that) to entice folks to submit their data in exchange for training in analyses that might speed up the process for some non-native English speakers to get their results published in top-tier international journals. The idea was to hold the meeting somewhere in Asia that was convenient for all participants, and not too expensive since our budget was quite limited. Since I was residing in Chiang Mai for several months each year, I offered to be a one-man local organizing committee (really two, to be fair, because of how much assistance I got from Orawan), and arranged to hold the meeting at the EFEO Chiang Mai center, just outside of Chiang Mais inner city wall and along the banks of the River Ping.

The meeting was three days long, and our primary objective was to use the newly contributed data (mostly tree rings, but some historical documentation-derived indices from Japan and China, some ice core data, and some lake sediment data as well) to produce a new temperature reconstruction from the Asian continent. Without going into too much detail here (stay tuned for that), we were not able to get a fully calibrated and verified reconstruction in the short time we had, and with the data set we ended up with, but we are a work in progress. There are a lot of difficulties associated with doing these kinds of reconstructions, not least of which is data quality control. At the end of the day, we are going to have about a 500-year temperature reconstruction for Asia, a far cry from the 2,000-year target, but better than a kebab skewer in the eye.

**********************

Usama grinned broadly and extended his hand to me and I shook it. He was genuinely grateful for the hospitality he was shown while in Chiang Mai, and his presence was one of the pleasant surprises for me. He and our Nepali participant, Narayan Gaire, were leaving the guesthouse together in a red sawng taew (the two-benched pickup trucks that are used in Chiang Mai as public transportation) to go to the airport. They had become good friends over the past few years having met at several regional workshops. These are fledgling dendrochronology programs in both of these countries, and it is remarkable to see the enthusiasm with which these two young men embrace learning this field of study. It will be because of the efforts of people like this that we are to have any chance of improving living standards across the globe, through education and engagement in the work the rest of us are doing — as equals and not perpetually as aid projects.

I was most impressed with these two fine young men, and I wished them both well on their journeys home. It saddens me terribly that our world is so unstable, and that we have the kinds of hatred that leads us to war with peoples in far flung lands, who have so little in material wealth, and yet strive to have the kind of enriched life that we take for granted. It is for that reason that I will think fondly of our little workshop, flawed as it was, and on my dinner with Usama, as a reminder of what is truly important.

And then the rains came …

Tree Stories - Fri, 01/20/2012 - 09:52

malee-nature-lovers-bungalowCHIANG MAI, THAILAND —  ”Rain never come in January.”  Malee had overheard me predicting heavy rain for the night, as the black clouds swirled around the steep limestone cliffs at the base of Doi Luang. The clouds tore off in little wisps of vapor, black and menacing, and rose upward, obscuring the jagged, orange-stained, overhanging wall that was visible from Malee’s Nature Lover’s Bungalows in Chiang Dao. She brought 4 cups of home-roasted coffee, a basket of home made spring rolls, and two plates of coarsely cut French fries, stacked high, to the table and set these down in front of us.

“Not big rain, like you say now” she continued, “sometime small rain only.”  She pronounced the word “small” as suh-mawn. As spelled in Thai based on its Sanskrit origins, words that end with the equivalent of the letter “L” are pronounced as we pronounce “N”, which is one of the more endearing things about Thai speaking English, to my ear.

Malee, always cheerful, has been a friend of ours for more than a decade. Orawan and I stumbled upon this amazing place in 1998 while looking for field sites. I was in search of the two Thai pine species that were reported to grow in the area, and we drove up the narrow road that dead-ended at an amazing cliff side Buddhist temple about 1 km past her rustic sign. At that time hers was the only guesthouse in this entire area, surrounded by empty fields and jungle, and local villagers foraged the nearby forests for bamboo, edible plants, and anything else of use. We stayed there one night and it seemed within hours we were friends, and we stayed with her numerous times until about 5 years ago when we stopped working in the region. Malee came to our wedding in Chiang Mai in October 2001, one month after the terrible 9/11 attacks. Coming back here now was like visiting family again after a long absence. In the years that have passed much has changed, and now there are guesthouses everywhere on this road, in the true Thai fashion of mimicking what has proven successful. But still, in spite of the oversupply of copycat businesses, Malee’s is an oasis of peace and quiet, and her business is very successful.

buddhist temple

Cliffside buddhist wat near Malee's guest house.

It is true that it is highly unusual for heavy rain to fall between December and April in northern Thailand, the months that comprise the driest part of the annual dry season. In the two decades that Malee has run her business, neither she nor any of her staff can remember heavy January rains like that which we were about to get. In most years it remains virtually rain free from late November until late April, when the heat reaches unbearable heights and the humidity boils up from the Gulf of Thailand. That is when the rains come, in May and June, not now.

The rhythm of the Asian Monsoon, as reliable as your own heartbeat, tracks the movement of the Intertropical Convergence Zone (ITCZ), which follows the migration of the sun’s most vertical ray from the Tropic of Capricorn in the Austral summer, to the Tropic of Cancer in Boreal summer — 23.5 degrees latitude in both hemispheres, respectively.  This is the stuff of Physical Geography 101, and I can still hear the booming voice of the late Dr. Dow, my undergraduate advisor and mentor:

“The ITCZ moves north and south with the seasons, and this means… What?… Brendan! What does it mean when the ITCZ moves north to 23.5 degrees latitude?” The fear that accompanied students in Dr. Dow’s classes was ubiquitous across the room, particularly for those inclined not to pay attention. I thought of Dr. Dow now, and how I am glad that I was one of the students who actually did pay attention.

“I don’t know, Malee, it sure looks like heavy rain to me.” I said.

“Not possible” she replied, “it not rain in January”.

Hours later, as the rain pounded the metal roof of our bungalow with hellish force for two straight hours I thought about how one of the lessons of the prior week’s workshop in Chiang Mai applied to the anomalous weather we were experiencing today. Dr. Andrew Bell, a post-doctoral fellow working with me for the past year, presented work we have been doing for our Greater Mekong Basin project that uses our long tree ring records to inform climate predictions with extremely simple models that even small-scale farmers might be able to use. There are predictions made by local religious leaders from nearly all countries in Southeast Asia, for example in Thai from the Nung Seu Bee Mai Mueng “Book of the Northern New Year” which gives some kind of guidance to farmers. What Andrew has found is that these predictions have some degree of predictive skill simply because climate has a tendency to show persistence from one year to the next, and to statisticians this can be modeled as autocorrelation.

brendan

Not only was it raining hard, it was cold too.

This feature of climate data is obvious when thinking about the seasonal shifts that we know well, for example, New York’s winter is cold, so there is a degree of correlation between January of one year and January of the next (i.e., both will be cold). The same is true for the dry season of Thailand — January will be dry in each year, hence the autocorrelation. The anomalous years, however, also tend towards persistence, such that if it is wetter or drier than usual (or colder or warmer, if you will) in a given season, the tendency to remain the same for the next year is slightly better odds than flipping a coin. So, if we assume persistence in the climate we can do a reasonably good job of predicting climate for the following season only. However, if we want to make informed 5-year or longer predictions, so that farmers might make more bold decisions about how and what to plant, and increase their profit margins, we need a better predictive tool than just guessing at persistence.

Andrew demonstrates that by using centuries or more of background data (e.g., long tree ring reconstructions of drought indices) one can do a pretty good job, far better than merely assuming persistence, at deciding what the next 5 years are going to be like, and the longer the record leading up to a given period, the better we do at predicting those next 5 years. The offshoot is more than just deciding what to plant, however. The real prize is in being able to use this information to give some form of blanket insurance to small-scale farmers, known as index insurance, which allows for coverage in case of drought or some other climate index value that is determined to be important. Interestingly, it is not the failure of the crops that is being insured, but the failure in the climate. Whether or not the climate adversely affects the crops is not relevant, as payout is made solely on the basis of climate. And by having lots and lots of small farmers buy into such a scheme, the greedy insurance companies can still make their profits and keep the costs low. For the GMB project, we are tasked with trying to find out how climate and its impacts can lead to conflict, what the parameters are for the conflict, and what factors are necessary to mitigate conflicts when they occur. We always believe that the past can help inform us of our present and our future, so using proxy records in these ways is done with this in mind.

doi luang after the rain

After the rain

The rain had ceased long enough for Orawan and me to walk out to meet our friends Paul and Anna, and their two children, Jonas and Amarita, who had gone out for a late lunch, and we joined them at the Chiang Dao Cave, about 2 km downhill from Malee’s. They sat out the rain in a small roadside restaurant, ordering food by pointing at things that looked appealing and hoping for good results. Paul and Anna are both seasoned travelers, and are no strangers to off-the-beaten-path locations, so they were enjoying their time in the village. We met them and strolled around the neighborhood, finding giant spiders and dead snakes, and an assortment of other horrible things the kids were fascinated with.

By the time we walked back to Malee’s it was near time for dinner, and the rain was beginning again. We had scarcely finished eating around 8:00 p.m. and walked back to our bungalow when the rain began in earnest. Broad sheets of water pounded the roof with a deafening roar until the morning light began to infiltrate our room. It was clear, that for today at least, the rains had come.

When it rains it pours. That phrase entered my mind, as I lay awake, eyes wide open, my wife breathing deeply beside me in the depths of slumber. Malee’s has always been one of the darkest places I have ever been at night, but on this night it was blacker than usual and I had a difficult time making out any features in the room through the impenetrable darkness. I had been having an inordinate number of interpersonal breakdowns with people lately, colleagues in particular, and I considered the notion that often things, negative things, come in groups or clusters, like rain falling. When it rains it pours.  I agonized over the role I may have played, either indirectly or perhaps through callous indifference, in developing these rifts with other people, and I wonder sometimes about karma, and about biorhythms or other phenomenon that can lead to such things. Or maybe it is just the way of the world that sometimes we enter anomalous periods and lots of shit goes wrong. My Vietnamese friends tell me that my age, 53, is a very unlucky year, as is 49.  I don’t remember much about 49, but in truth my 53rd year has been an outstanding year on many fronts. However, whatever is wrong with the cosmos lately that has me offside of so many people could be just a passing anomaly that will wash away, run off or be absorbed like the heavy January rains on the limestone flanks of Doi Luang.

The message of the day resonated with me.

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