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State Rethnks Piermont Marsh Herbicide Plans - (Rockland, NY) Journal News

Featured News - Thu, 11/07/2013 - 10:44
Phragmites may be considered an invasive plant, but it helps buffer shorelines from waves during heavy storms, says Lamont's Klaus Jacob.

Climatologist Studies Past Sea Levels to Predict Future - Columbia Record

Featured News - Wed, 10/30/2013 - 11:00
Profile of Lamont-Doherty climate scientist Maureen Raymo.

Oceanographer Studies Clues to Global Warming - Columbia Record

Featured News - Wed, 10/30/2013 - 11:00
Profile of Lamont-Doherty microbial oceanographer Sonya Dyhrman.

The Pluvial Continues… Has the Long Rain Epoch Begun?

The Broadleaf Papers - Sun, 09/15/2013 - 20:04

It was midday. It was dark. It was June! It was pouring. We were sitting in my folk’s cabin in the Adirondacks when my dad groaned, “This is depressing”. Later on that same day, a hometown friend made a similar exclamation. Elizabeth’s update triggered a deluge of similar sentiments. During that discussion, she made reference to The Long Rain. It was the perfect comparison. Judging from the sentiment in our cabin, in the newspapers, and on Facebook, Central New York was on the edge of insanity because of the unrelenting rain.

 N. Pederson

A deluge during the Long Rain of June 2013 at Black Rock Forest. Photo: N. Pederson

 

It was too early in the season to write this post. Predicting future rainfall is like trying to predict Dennis Rodman’s next career move: It will move in a new direction, but no one can pinpoint the trajectory. But now, as Cortland and Macoun apples grace us with their presence, we can now safely say that summer is over (I do not care what the tilt of the Earth says. It is apple season!). In fact, the Northeast Regional Climate Center and NOAA have completed an early overview of this past summer’s climate. Their conclusion regarding precipitation in the Northeastern US? The Pluvial continues.

 it was wet in the NYC region. Image from NOAA's climate summary page. Hat Tip to Stockton Maxwell for sharing this graphic with me.

NOAA August and Summer 2013 summary of significant events. Hint: it was wet in the NYC region. Image from NOAA’s climate summary page. Hat Tip to Stockton Maxwell for sharing this graphic with me.

 

Actually, these overviews typically discuss climate of just the most recent month or season year or versus the “climate normal.” While useful, these summaries do not paint the full picture. Consider this: A climate normal is often based on a recent 30-year period, like 1970-2000. Now consider this: Instrumental records for the Northeastern U.S. (below) and analyses for the Catskills region and southern New York State, here and here, indicate that since the 1960s drought, the region has seen a substantial increase in precipitation; in fact, hydroclimate seems quite unusual since 2000. Now really consider this: A tree-ring reconstruction of moisture availability indicates that the recent wetting comes at the end of a 120-180 year trend (and maybe longer). So, the daily comparisons on TV or other media sources are typically based upon recent climate and ignore the past. Thus, based upon paleo records, the full picture indicates that we are sitting in one of the more unusually wet periods of the last 500 years.

Northeastern US summer precipitation from 1895-2013. 2013 is the second wettest summer on record for the entire region. Data and image procured from NOAA.

Northeastern US summer precipitation from 1895-2013. 2013 is the second wettest summer on record for the entire region. Also note the only two years since 2002 are below the average since 1895. And, they are marginally below the mean at best. Data and image from NOAA.

 

I return to this topic because of: 1) the many implications of this climatic shift and, most importantly, 2) what seems to be a limited amount of public awareness of how wet it has become in recent decades (though this awareness is growing). The substantial change in moisture across the Northeastern U.S. (the draft of the 2013 3rd assessment is here) is more commonly known in the scientific literature, but it seems to be less well-known outside of that community. For example, under the tab “Climate Change” on the Northeast Regional Climate Center’s excellent web resource, one can only find minimum and maximum temperatures when seeking to understand how much the climate has changed. An increasing trend in precipitation just doesn’t seem to grip the attention of most people like an intense heat wave or drought. In fact, an editor remarked to a freelance writer that they’d only do a story on the change in precipitation in the NYC region if “they were painting the lawns green on Staten Island.

For the people in Vermont, the Catskills, Mohawk Valley, and those wishing to use beaches in the summer along the coast, this seems a bit short-sighted. Excess rain is costly. It costs the people still trying to rebuild in the Catskills from the flooding of 2011 (and it isn’t just the two tropical storms that triggered the flooding – new research indicates that because the soils were saturated, the impact of Irene and Lee were worse than they might have been in other times). It costs people in Vermont wanting to rebuild their cultural heritage. It will cost all of us in NY State if tax breaks are given to expand flood relief measures in five counties and restoration and reconstruction of managed water systems; climatic change disregards political boundaries. It might cost us if we are managing forests for a long-gone climatic era. It further erodes trust between country and city folk as well as citizens and their government. Tragically, it costs lives.

So, as we become aware of the impacts of additional rainfall (and certainly there are additional costly impacts than what is listed above), we need to know that precipitation is likely to increase over the coming century. Model projections indicate it is likely that the Northeast will get wetter and have more extreme rain events. This doesn’t mean we will not experience droughts in the future, nor does it mean each summer will be like 2011 or 2013. And, these model projections could be wrong. But, our state of knowledge indicates that these Long Rain conditions could become more common.

This shouldn’t be viewed as more environmental doom and gloom. Humans have enormous brains and know how to use them! See: Klaus Jacob. We have the ability to prepare for potential adversity. And, if it isn’t clear by now, humans are one of the more adaptable and flexible animals on the planet. Heck, we might even celebrate wetter conditions with some enormous fun. And, from my Broadleaf perspective, the Northeast could become a temperate rainforest with bigger trees and a denser forest.* Folks spend enormous money to experience such things.

 N. Pederson

Dario Martin-Benito and Javier Martin-Fernandez in the Oriental beech dominated Colchic temperate rainforest in the Mtirala National Forest of the Republic of Georgia. Photo: N. Pederson

 

 

 

 

 

 

* unless future warming overwhelms our rain wealth and stunts the future forest…. apologies. It is hard to avoid all of the potential doom and gloom…

 

Service outages

IT Announcements - Tue, 09/03/2013 - 11:14

We are experiencing trouble with a home directory server this morning. It is affecting 40-50% of our users. Multiple short outages may continue throughout today and tomorrow as we prepare and execute plans to migrate users to another server. We apologize for this inconvenience and appreciate your patience as we work to resolve the problem.

Seismology as Performance Art

Jim Gaherty installs a seismic station in Masoko as a crowd looks on

Jim Gaherty installs a seismic station in Masoko as a crowd looks on

Ideally, seismic stations are sited in remote, quiet locations away from any possible cultural noise, especially people, who are very noisy (even if they are not New Yorkers). But other considerations besides peace and quiet are important for a good station, particularly security. As a result, we placed most of our stations in towns near schools, hospitals or town halls, where people could keep an eye on them.

We often attract crowds while installing our exotic seismic gear. Field work with an audience has pros and cons. It’s certainly somewhat distracting to labor and sweat under the sun, tinkering with wires and programming equipment with a big crowd in attendance. Some of the sites are in relatively tight spots, so the curious onlookers occupied much of our working space, making for very close quarters. Several days ago, we installed a station next to the village hall in Ndalisi as a small crowd looked on and an animated town meeting took place next door. Loud passionate speeches inside were matched by loud banging outside as we mounted a solar panel for our station on the roof.

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Students from the Ilindi elementary school watch from a distance

But there are very big upsides. People from the villages where we deployed stations have provided an enormous amount of help with building our sites. We have also had abundant opportunities to tell people what we hope to learn about the active tectonic environment where they live. Continental rifting here gives rise to geohazards such as earthquakes and volcanoes. Because we have tried to locate many of our sites near schools, we particularly hope to communicate our science to students and teachers. At the Matema Beach High School, students peppered us with questions as we installed our gear. Their school is just a stone’s throw from the Livingstone Mountains, the surface expression of a major rift fault that has caused large earthquakes. But our seismic installations admittedly may not be entirely positive; today at Kifule Secondary School, students took a long math exam inside while we were making a racket outside. But hopefully the pros out weigh the cons… Even at Kifule, students burst out of classroom after the test all smiles, so apparently we were not too disruptive.

Surface Views of the Southern East Africa Rift Inspire a Look Underground

P1040254

Kiejo volcano in the Rungwe Volcanic Province with a cinder cone

Driving around the Rungwe volcanic province in the southern East Africa Rift installing seismometers, we have the chance to observe first hand how geological processes in action create the most dramatic forms at Earth’s surface. Looming volcanoes flanked by cinder cones lie along the rift valley, often very close to rift faults. The Livingstone Mountains, the surface expression of a major fault system that bounds the rift to the east in this area, soar over 1.5 km over the valley below, including Lake Malawi (Nyasa).

P1040454

The Livingstone Mountains, which are the surface expression of a major rift fault

The remarkable geological structures evident above ground motivate us to look deeper in the earth. We see volcanoes in particular places at the surface, but where are magmas located at depth below the volcanoes and the rift? Likewise, we see dramatic faults that are helping to thin and break the crust at the surface, but how do they relate to stretching of the entire crust and lithosphere beneath this part of the East Africa rift? And how are the magmas and faults related to one another? These are the core scientific questions motivating our study of the rift around northern Lake Malawi (Nyasa). We hope to use data collected during this program, including the 15 seismic stations that we are deploying now around the Rungwe province, to answer these big questions.

Imaging beneath the southernmost volcanoes in the East Africa Rift

The last time we visited the southern part of the East Africa Rift, we were responding to an unusual series of earthquakes in December 2009 that shook northern Malawi. The faults responsible for these events had not produced any earthquakes historically, and thus caught everyone by surprise. The unexpected occurrence of earthquakes on these faults highlights our poor overall understanding of how the African continent is slowly stretching and breaking apart.

This time, we return to this part of the rift system as a part of a more comprehensive effort to understand the underpinnings of this continental rift using a spectrum of geological and geophysical tools and involving a big international team of scientists from the U.S., Tanzania and Malawi. In the coming three weeks, we plan to deploy ~15 seismometers in southwest Tanzania around the Rungwe volcanic province, the southernmost volcanism in the East Africa Rift system. These stations will record small local earthquakes associated with active shifting of faults and moving of magmas at depth. They will also record distant earthquakes that can be used to create images of structures beneath Earth’s surface and map the faults and magmas.

Rungwe seismic deployment

Map showing elevation and lake depth, locations of volcanoes (red triangles, from Smithsonian Global Volcanism Program), major faults (black lines) with planned locations for seismometers. We plan to deploy 15 stations (light blue circles) in the next three weeks around the Rungwe volcanic province. Dark blue circles show tentative locations of stations to be deployed in the summer of 2014.

 

Only 144 Miles, Yet Worlds Apart

Peering Through Polar Ice - Sun, 08/04/2013 - 11:25
The icepod team at Raven Camp, Greenland Icesheet. (Photo M. Turrin)

The IcePod team at Raven Camp, Greenland ice sheet. Photo: 2nd Lt. C. Martin, NYANG

144 miles separates Kangerlussuaq from Raven Camp. Not far really, just 144 miles – like traveling from the southern tip of New York City up to Albany. Flying at 270 knots we can be there in about half an hour, no time at all, and yet to the casual observer they seem worlds apart.

Kangerlussuaq Greenland on the Sondrestrom Fjord. (Photo M. Turrin)

Kangerlussuaq Greenland on the Sondrestrom Fjord. Photo: M. Turrin

Kanger sits nestled in the arm of Sondrestrom Fjord, where over the years Russell Glacier has found the soft belly in the rock base, wearing the surface down flat and pushing the rock flour out to sea. Currently the tip of Russell Glacier is a full 20 kms (14 mi) up the fjord. In the summer months, as research teams move through the village, glacial meltwater fills the carved channel that borders the small town.

Meltwater Rushing Behind Kangerlussuaq, Greenland

“Summer meltwater from Russell Glacier rushes around the edge of Kangerlussuaq.”

Although modest in size by our standards, Kangerlussuaq is a transportation hub for Greenland, and has a steady year-round population of ~500 residents.

Population at Raven Camp. (Photo M. Wolovick)

Raven Camp population posting -  “Pop. 2.” Photo: M. Wolovick

Raven Camp sits high up on the Greenland Ice Sheet on a frozen bed of ice, almost 2 kms thick (~1 mi) and millions of years in the making. At almost 7,000 feet of elevation, no seasonal change will bring a rushing river or a population to match that of Kangerlussuaq, but summer research does bring an influx of summer scientists, swelling the population beyond the posted total of 2. With a handful of tents and collapsible housing structures, Raven Camp is a summer town.”

Icepod collecting data as part of the Raven Camp grid. (Photo M. Turrin)

IcePod tucked up for transit to Raven Camp, where it will be lowered to complete the survey grid over the ice landing strip. Photo: M. Turrin

Today we fly to Raven Camp to complete a survey grid over the ice landing strip. A year ago the camp staff detected several cracks (crevasses) in the ice running perpendicular to the airstrip. Crevasses are to be expected around the edges of an ice sheet, where the ice is faster flowing, however, at this elevation and this far inland it is more unusual. Published data for ice movement in this area shows at the base the ice is moving about 2.5 cm a day, while at the surface ice is moving closer to 7 cm a day. It is no surprise that the ice at the base moves more slowly, a result of the increased friction at the bed causing the ice to stick and slow.

Dye 2 facility at the Raven Camp established during the cold war as one of four sites in Greenland that were part of the U. S. Distant Early Warning Line, a system of radar stations to warn of incoming Soviet bombers. (Photo M. Wolovick)

Dye 2 facility at the Raven Camp established during the cold war as one of four sites in Greenland that were part of the U. S. Distant Early Warning Line, a system of radar stations to warn of incoming Soviet bombers. Photo: M. Wolovick

Currently measuring only 10 cms across, it certainly doesn’t seem that this could cause much trouble. But if the crevasses are deep and continue to widen, they will threaten the landing strip. A team of scientists has been collecting measurements on the ground to see if these rates are changing (2013 polarfield blog1); our job is to survey the area with our instruments. The Shallow Ice Radar and the infrared camera collect the depth of the cracks and the temperature differences as the cracks move deeper into the ice. Pulling all this data together will help us understand what is happening to the ice in this area.

The Shallow Ice Radar collects images through the upper layer of ice. (Photo M. Turrin)

The Shallow Ice Radar collects images through the upper layer of ice. Photo: M. Turrin

Our flight grid will be flown low, at 1,000 ft. above the ice surface, one third our normal survey elevation. Two East/West lines are flown perpendicular to the landing strip at 600 meters apart. Then three tie lines are flown parallel to the runway at 100 meters apart.

 

 

 

 

Once the grid is complete, we land on the airstrip, testing the seal on the pod door and collecting some camp cargo. The landing is smooth.

Nick Frearson, lead engineer on the Icepod project prepares to check the pod for snow after the ice runway landing at Raven Camp. (Photo M. Turrin)

Nick Frearson, lead engineer on the IcePod project, prepares to check the pod for snow after the landing on the ice runway at Raven Camp. Photo: M. Turrin

Temperatures today at Raven are a warm 1°C. The snow has lost some of the crispness we had experienced when we had landed in April to install a GPS on the ice. The pod is inspected. The camp looks all but abandoned, yet a snow vehicle appears with cargo that is stashed and secured for transit. While the cargo is loaded, we snap a quick IcePod team photo.

Cargo is loaded into the back of the LC130 at Raven Camp. The aircraft is not turn off during ice landing - all loading is done quickly. (Photo M. Turrin)

Cargo is loaded into the back of the LC130 at Raven Camp. The aircraft is not turned off during ice landing — all loading is timed with the ground for a quick exchange.(Photo: M. Turrin

The new eight-bladed propellers on Skier 92 do their job and the take-off is smooth for our return to Kangerlussuaq, just 144 miles, 30 minutes of transit, and yet seemingly worlds apart.

1 For more on the science being collected on the ground on ice movement: http://www.polarfield.com/blog/tag/greenland-ice-cap/

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

 

 

 

 

 

 

 

 

 

 

The Langseth cruise is winding down!

Mapping the Galicia Rift off Spain - Thu, 08/01/2013 - 09:32

The Langseth Galicia 3D seismic cruise is winding down. By tomorrow we will be back at the dock in Vigo. Like most seagoing science, we will miss the ship experience, we will miss the new colleagues we have met, we will look forward to getting back on shore, and for many of us the awesome multi-year task of processing, interpreting, and publishing the boatload of data we have acquired.

This is an example of the data we have collected. Right is to the East and left is to the West. This is a cross section of the Earth about 65 km long. The blue is water. The water depth here is about 5 km. The red and gray colors are a cross section of the rocks below the water. The flat layers are sedimentary rocks. The lumpy bumps (that is a technical term!) consist of blocks of continental crust and of the mantle.
We thank the Langseth’s Captain and crew for making this possible! These are men and women who live on the sea, and who share their ocean world with us for a month or two. Every now and then, when you can walk 100 meters in a straight line, ask yourself, “Where is the Langseth now, and who is steering the ship, or keeping the engines running, or keeping the deck ship-shape, or providing good food, or every other important task on the ship?” Under your breath say thank you for the experience you had on Langseth.
We thank Robert and his technical team. They worked tirelessly to assemble the 24 km of hydrophone streamer that hears the reflections from the Earth, the 40 or so airguns that make the booms, and all the rigging it takes to tow them spread out behind the ship over 600 meters wide and 7000 meters long. That was just the start. Then they operated the electronic equipment that received the seismic data and recorded it for the scientists. Without them we could not do the science we love.
Thank you to the Science Party. We had a total of 20 scientists, including undergraduate students, graduate students, post-docs, researchers, and professors. On Leg 1 we had 14 scientists and on Leg 2 we had 10 scientists. Four scientists weathered both legs. Six joined us for Leg 2. I am very grateful for all your efforts on behalf of the Galicia 3D science. I hope that you learned a lot, had a good time, and met other scientists for the first time. I suspect that we will meet one another many times in the future.I look forward to that!


This is the Technical team and the Science team for Langseth Leg 2.
I want to thank the Protected Species Observers for sailing with us. They spent countless hours in the observing tower, high above any other part of the ship. They have sighted hundreds of whales, but most did not come close to the ship. It is windy and cold up there, but their role is important for making sure that collecting our scientific data does not interfere with the creatures who call the ocean home.
Thank you for sending your loved ones off on the Langseth. I can certify that they now know how to do their own laundry and to clean up their cabin before they leave the ship. During the weekly emergency drill, they run quickly up to the muster station on deck and put on safety gear. I recommend that you continue to enforce these behaviors ruthlessly! They will forget them if you let them slack-off. On the other hand, they did not have to cook their own food, or wash and dry their dishes. You will still have to work on these behaviors!
As I write this from the Langseth, we should remember that the Galicia 3D experiment goes on. Our colleagues from GEOMAR and University of Southampton will be on the FS Poseidon from 25 August to 10 September. They will be recovering the 78 Ocean Bottom Seismometers that are still on the bottom (on purpose!). They have been recording approximately 150,000 airgun array shots fired by the Langseth. I know what you are thinking. “How many total recordings of shots are recorded in all the OBS’s?” That would be about 11.7 million shot recordings. This will keep the OBS scientists busy for a while!
I particularly want to thank James Gibson for creating this blog. It has reached out to our friends and to strangers. We plan to keep the blog alive. This project will continue for years.

Best regards,Dale SawyerRice University

Behind the scenes of the ship

Mapping the Galicia Rift off Spain - Wed, 07/31/2013 - 12:26

This week we have been exploring all the parts of the ship we have not yet discovered and were lucky enough to get shown around the engine room and the bridge. It is evident that each area of a ship (bridge, engines, science etc.) has a group of people doing those specific jobs and that the combination of everyone doing their part keeps everything running smoothly; like cogs in a massive machine. 
The engine room control panel. With that many buttons no wonder it takes so much training to work in the engine room!The engine room is located in the hull of the ship and is the biggest room on board by far, taking up about 2/3rds of the bottom deck. This is obviously a very important part of the ship because without it we would not be moving anywhere! The Langseth has 2 engines leading to 2 propellers and also 1 bow-thruster. There are so many different bits of machinery down there that it can take 4 years of studying to be qualified to work in the engine room. It is very loud and warm but surprisingly clean and tidy. There are also 2 compressors which are used to pressurise the air for the air guns that we tow. 
One of the very noisy compressors. It is hard to portray the size of these in a photo, they are huge!The heat from the engines is used to produce all the hot water for the ship and the engine room also has machines for desalinising our water. Fuel usage is constantly monitored and fuel moved between all the many tanks spread around the ship to ensure even weight distribution. Even though we only travel at about 4 knots whilst acquiring data we burn between 5000-6000 Gallons of fuel a day due to the massive load of the equipment we are towing behind us.
One of the two enginesThe bridge sits at the front of the ship on top of the main living quarters. From here it seems as if practically everything can be controlled. They drive the ship when we are not driving from the main science lab during acquisition, control the speed, can manage the safety aspects including all alarms and watertight doors and keep a look out for anything floating past that might get caught up in our seismic gear (so far buoys and pallets have been sighted). One very important job of the bridge is to communicate with other nearby vessels. Nobody would expect us to be towing 6km of streamers so we have to make sure we let other ships know with enough time to arrange safe passing, therefore avoiding collisions.
This is the main control panel in the bridge. There are screens for  navigation and
radar as well as all the speed controls. There are two smaller control panels
on the port and starboard sides of the bridge for work that
involves careful maneuvering e.g. picking up OBS's. The last seismic line is just being finished right now and then we can get ready to begin equipment recovery. It is about 40 hours until we are back on dry land again! 
Tessa GregoryUniversity of Southampton  

Binning is the name of the game

Mapping the Galicia Rift off Spain - Wed, 07/31/2013 - 03:44
As we come to the end of our cruise I thought that now would be a good time to talk about the way in which both seismic and multi-beam sonar data are quantified (basically nerd out). In both cases we "bin" the data into grid cells, which are predefined based on the resolution that we expect to achieve given the ideal data density of individual cells within the grid. 

A screen capture from the multi-beam sonar Seafloor Information System (SIS).
The image on the left shows swath coverage. The image on the right shows an active ping through the water column.Multi-beam sonar (swath seafloor mapping) data are collected, gridded (binned) to the predefined cell size, and output in two flavors. Bathymetric grids, which are essentially 3D topographic maps, and Backscatter grids, which display the reflectivity of the seafloor. The reflectivity varies due to both incidence angle of the respective beams and the density of the surface (e.g. hard rock, sediment etc). As the ship moves along at a given velocity, the multi-beam sonar sends a "ping" from the transducers (transmitters) to the seafloor and then waits until the receipt of the last return to ping again. The ping rate (Hz or 1/seconds) is a function of the depth of the ocean as well as the sound speed through water (XBT's are useful!). The swath width also scales as a function of depth. Our average depth is ~4800m (2.98 miles), which allows for an achievable swath width of ~20km (12.43 miles!).
Swath coverage display of the backscatter (reflectivity of the seafloor) collected across a swath.In order to gain insight on the density of the multi-channel seismic (MCS) data that we are collecting we use the Spectra software package. Spectra tracks the position of the ship, streamers, and air guns in real time using GPS and an acoustic network, and then bins the data accordingly within the predefined grid. The goal is to get an equal amount of seismic traces (reflected seismic waves) in each bin. The traces can then be stacked (combined), which increases the signal to noise ratio. Stacked traces within a bin are called "fold" and ideally represent traces from all offsets along the streamer in respect to the source.

A screen capture of the Spectra display. The image on the left shows active binning of the MCS data.
The image on the right shows the bins being infilled (filling holes).We are getting to the end of the "No Mores," which means we are finished on Friday!! Stay tuned for a word from our Chief Scientist along with a look at the MCS data (and our cruise pic). 
James GibsonLamont-Doherty

Gone Fishing…Took IcePod!

Peering Through Polar Ice - Tue, 07/30/2013 - 21:19

 

Surface meltwater lake.

Ice sheet surface meltwater lake. (Photo: M. Turrin)

When the New York Air National Guard travels to Kangerlussuaq, they toss in a few fishing poles with the baggage for whatever few hours of free time might be available. A favored pastime for this location’s summer assignments means the local lakes are well known by the crew, so when we sat down to map out the flight plan, a request for locating lakes met with an easy nod. No problem at all. It took only seconds to register that our definition of lakes might differ from theirs.

Icepod 'lakes' are actually surface meltwater pools on the icesheet. (photo M. Turrin)

IcePod ‘lakes’ are actually surface meltwater pools on the ice sheet. Photo: M. Turrin

We are interested in lakes atop the ice sheet surface, places where the ice sheet melt is puddled into lakes of various sizes. It is in locations like these lakes where water, with its darker color, absorbs more heat from the sun than the surrounding white ice surface. This process can contribute to more melt, and in some instances the water finds a weak “joint” in the ice and drains right down to the bottom. Both the extent of the ponding and this process are of interest to the science community in better understanding the ice sheet.

The guard is quick to assure us, no problem, these too can be located!

Chris Zappa,oceanographer and project optics expert, peers out the window of the LC130 aircraft.

Chris Zappa, oceanographer and project optics expert, peers out the window of the LC130 aircraft. Photo: R. Bell

It was an “optics day,” where our focus is on the cameras in IcePod. Using both our Bobcat (visible wavelength) and our (IR) infrared cameras, we will image surface lakes and the meandering meltwater channels on the ice sheet surface, and then fly over a few of the southwest fjords to image meltwater as it plumes at the calving edge of the ice sheet. This is a day that Chris Zappa, our resident oceanographer and optics expert, has been waiting patiently for. The weather is perfect, the sky crystal clear, and the instruments are humming. We are ready to go.

Surface feature on the ice that appears to be a meltwater channel that has been covered over by blown snow. (Photo M. Turrin)

Surface feature on the ice that appears to be a meltwater channel that has been covered over by blown snow. Photo: M. Turrin

The surface of the ice sheet barely resembles our April visit. Large lakes, some a mile across, are printed along the ice sheet surface, as if a skipping stone has skimmed along the surface leaving pockets of water in its wake.

Icepod Visible wavelength camera captures the meltwater lake as we fly overhead. (Photo M. Turrin)

IcePod visible wavelength camera captures the meltwater lake as we fly overhead. Photo: M. Turrin

These ice surface lakes are viewed more cautiously than our lakes back home, as they pose a threat of suddenly emptying through a “moulin” or drainage tube. Moulins transfer water from the surface to the bottom of the ice sheet in short order, circumventing a process that could otherwise take many thousands of years. Cutting across the surface in various patterns, meandering channels carry the melting surface water into these catchment pools. On the ice sheet these channels are the equivalent of streams from our home communities. Back home they collect runoff and drain into freshwater lakes. Here they serve the same function but are more striking, as there are no plants to screen them.

The tip of the icepod can be seen as we move over this meandering meltwater channel on the icesheet. (Photo M. Turrin)

The tip of the IcePod can be seen as we move over this meandering meltwater channel on the ice sheet. We imaged some of these channels in April. From the plane their frozen surfaces had appeared flat and greytone. Now they are deeply cut and etched, filled with a sparkling aquamarine coloring as the ice has warmed, experiencing some summer melt. Photo: M. Turrin

Icepod images over the heavily crevassed surface of the icesheet. (Photo M. Turrin)

A dense pattern of crevasses cuts across the ice surface, darkened with scattered dust and debris along the edges of the ice sheet, clearing to toothpaste white as we move to the interior. IcePod captures images as it moves over the heavily crevassed surface of the ice sheet. (Photo M. Turrin)

The cameras work furiously. The Bobcat, is a 29-megapixel camera. The IR samples at 100 frames per second. Both cameras collect a staggering 60 gigabytes a second. Images play across the screen showing the temperature contrasts as we move over the surface features.

At the calving front of the glacier meltwater and sediment plumes are among the processes the icepod cameras are capturing. (Photo M. Turrin)

At the calving front of the glacier meltwater and sediment plumes are among the processes the IcePod cameras are capturing. Photo: M. Turrin

We move from the ice sheet to the coastline, where rugged mountains circle Greenland’s perimeter like a crown. Fjords cut through in many areas, allowing deeply stacked ice in the interior to move off the land. Today we are flying down small “arms” of Godthaab Fjord with a focus on their leading edges, where the ice meets the Atlantic water. We are interested in how the IR camera can be used to track thermal plumes at the interface of the cold glacier meltwater and the warmer ocean water. Combining both the Bobcat and the IR cameras allows sediment plumes to be tracked moving through the fjord. Sediment should warm faster than the surrounding water, and may be transferring more heat into the system. Both will tell us about circulation, mixing and transit of the glacial meltwater systems.

Small fishing village along the edge of a fjord in southwestern Greenland. (Photo M. Turrin)

Small fishing village along the edge of a fjord in southwestern Greenland. Photo: M. Turrin

Flying back down the fjord we pass over a small fishing town perched on the edge of the water. There is no apparent movement below. Perhaps they have gone fishing?

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

‘Lipreading’ the Icesheet

Peering Through Polar Ice - Mon, 07/29/2013 - 17:47
A view from the cockpit of the LC130 aircraft as it moves over the Greenland Icesheet. (Photo M. Turrin)

A view from the cockpit of the LC130 aircraft as it is maneuvered down the fjord by the New York Air National Guard up onto the Greenland ice sheet. Photo: M. Turrin

Even the most skilled of English language lipreaders are only able to tease apart about 30 percent of the information being shared. I learned this reading a recent article (Kolb, 20131). The author, herself deaf, went on to note that in some transmissions the information capture is higher while in others there is nothing collected. An average of 30 percent information transfer…most of us seek more information, we are curious beings. I don’t know anyone who is happy to sit comfortably saying “yes we know 30 percent, that is good enough.”

The team heads to the aircraft at Kangerlussuaq Airbase. (Photo M. Turrin)

The team heads to the aircraft at Kangerlussuaq Airbase. Photo: M. Turrin

I am surrounded by question posers, information seekers, hypothesis formers – scientists are an inquisitive bunch for sure – and that is how we find ourselves back in Greenland in July seeking to learn more about the information operating underneath and deep inside this changing ice sheet, and testing just what our IcePod instruments are capable of telling us. Thirty percent is well in excess of what we currently know about ice sheets and their processes, but every line flown and piece of data collected and analyzed builds upon our current understanding.

Moving onto the edge of the Greenland Icesheet flying up Sondrestrom Glacier. (photo M. Turrin)

Moving onto the edge of the Greenland ice sheet flying up Sondrestrom Glacier. Photo: M. Turrin

Prior to arriving at the base for the morning, flight plans were laid well in advance. Discussions threaded through the series of meetings leading up to our return to Kangerlssuaq, piecing together the right combination of flights that would focus on testing instruments and addressing the science. Instrument range, elevation, seasonal snow conditions, old radar lines all are factored in. Once in Greenland we must weave weather and instrument issues into our planning. Weather is cloudy and reports suggest an improvement during the week, so we will shelve our camera testing for the minute and focus on instruments designed to penetrate through the clouds. Today our flight will focus on tuning our Deep Ice Radar System (DICE).

Tej Dhakal and Chris Bertinato confer over the radar data. (photo M. Turrin)

Tej Dhakal and Chris Bertinato confer over the radar data. Photo: M. Turrin

Located at the crest of the ice sheet the elevation is just over 10,500 ft. and seems just the place to test our deep ice radar. Once aloft, we head for deep ice up over Summit. The weather reports are validated – the whole area is socked in with cloud cover and the pilots switch to Instrument Flight Rules (IFR). Our survey flight at Summit is 3,000 ft. above ground level (agl), but the aircraft instruments tell us we are 13,000 ft. above sea level (asl). The ice is deep and DICE is the focus of the next few hours as we survey and resurvey in the same area with dialogue, testing, refining and learning with each pass.

Nick Frearson, Robin Bell and Mike Wolovick discuss the possibilities of continuing the flight line or adjusting to focus the day's efforts. (photo M. Turrin)

Nick Frearson, Robin Bell and Mike Wolovick discuss the possibilities of continuing the flight line or adjusting to focus the day’s efforts. Photo: M. Turrin

A question was raised — would we want to move to a second area to look at different conditions? Checking other areas of the ice sheet is tempting, but the science team vetoes this…”We learn more by doing this now,” holding our focus on one location. So we refocused our efforts, collecting more data, making more small adjustments, and consider that with each data point we are improving our lipreading of the ice sheet.

Mike Wolovick and Tej Dhakal troubleshoot radar data wearing appropriate eye protection gear! (Photo M. Turrin)

Cool Dudes! Mike Wolovick and Tej Dhakal troubleshoot radar data wearing appropriate ice sheet eye protection gear. Photo: M. Turrin

For more about IcePod: http://www.ldeo.columbia.edu/icepod.

1Kolb, Rachel, Seeing at the speed of sound, in Standford Magazine, March/April 2013 http://alumni.stanford.edu/get/page/magazine/article/?article_id=59977

Nom, Nom, Nom: Meals aboard the R/V Langseth

Mapping the Galicia Rift off Spain - Mon, 07/29/2013 - 07:15

After all these posts about how we live and work onboard the R/V Langseth you may just be wondering what sort of sustenance keeps us going during the long hours.  Well you’re in luck! The excellent cooks serve meals with a smile promptly three times a day at 7:20 am, 11:30 am, and 5:30 pm.  Breakfasts always include mountains of eggs, bacon, sausages, and pancakes and on special occasions scrumptious muffins.  Lunch usually comes with toasty grilled sandwiches, soup that warms your limbs, and crunchy French fries.  Dinner varies but commonly consists of a juicy steak or pork chop, rice, mashed potatoes that put even your Mom’s Thanksgiving potatoes to shame, and a delicious desert like cherry pie.  The salad bar is open 24 hours a day and even this far into the cruise still contains crisp spinach, olives, tomatoes, and a variety of other vegetables.A sampling of the meals served onboard with cooked by the always smiling galley staff.
From left to right breakfast, lunch, and dinner.
In the center image the galley staff made up of June, Hervin, and Brian pose behind a lunch of pizza and soda.We are now in the home stretch of our cruise, steaming furiously down our final sail lines to complete our 3D grid.  Can’t believe there’s only four more dinners until we set foot back on dry land!
Natalie AccardoLamont-Doherty

5 lessons I have learnt on my first scientific cruise

Mapping the Galicia Rift off Spain - Sat, 07/27/2013 - 08:40

I was sent to join this cruise half way through because a lot of the scientific party had to leave and nobody more qualified than me could be found at such short notice! I have never been on a cruise before and had no idea what to expect, or any idea how complex and time consuming 3D seismic acquisition is. I have learnt so much about the technical side of acquisition and a little bit about the processing side; however I have also gained a lot of non-scientific tips and tricks!

Here are my top 5 tips: 

1) ‘Boring science is good science’ – If you are bored on a 6 hour watch that is a good thing because it means that everything is running smoothly and good data is being collected. Having things to do is always a bad sign! Things have been running pretty well recently and as a result I have greatly improved my crossword skills.

2) Things will break, don’t panic! – This is a hand me down ship filled with second-hand instruments from industry vessels. Because of this a lot of the equipment is temperamental and repeatedly needs to be fixed. However, I have also seen instruments that have been offline for days randomly start working again so you never know!

3) Duck tape has a million uses – There is no end to the list of things duck tape is used for on this ship: keeping weights in place on streamers, keeping your laptop on the desk during bad weather, taping your ladder to your bunk so it doesn’t bang during rough weather and keeping ropes in place on the deck to name a few. It seems like any problem can be fixed with tape.
If you don't want your office chair rolling around or you need a cable tie just use tape!
4) Hoard food – When food you like is put out in the mess then take it while you can. A few days ago a gigantic tub of mini snickers and bounty bars was put out in the mess….I have never seen chocolate disappear so fast!

5) Taking a shower is the most dangerous activity on the ship – I recommend keeping either an elbow or hand on the wall at all times so you can feel when you start to move. I think taking a shower is probably the best form of exercise on the ship because of the amount of effort and energy it takes just to balance. Also, never soap the bottom of your feet in rough seas. That is probably classified as an extreme sport!

Tessa GregoryUniversity of Southampton

Free Time: Let's see what we have here!

Mapping the Galicia Rift off Spain - Fri, 07/26/2013 - 11:35
As Natalie told you, the Main Lab operates for 24 hours a day, but we have a 6 hour shift (nobody can work for 24 hours of course!).  So, what are we going to do in our free time? That is a great question!  Let me show you the Marcus Langseth's free-time facilities.

Located next to the Galley we have our Library which has a lot of good books (I was reading the Che Guevara's travel book before the beginning of this part II, I really want to finish it!) and these excellent chairs...they're really comfortable, believe me. You can also find a variety of mystery, fiction and scientific books on the shelves.
The library with a wide variety of books
Yeah, but John actually I'm not a book lover ...No problem! This is what you need! A 42-inch TV screen and a big collection of movies and TV shows. Ah, and don't forget the PS3, which makes the crew's free-time fun.  I have to admit something to you, I've never used the movie room, but maybe sometime I will go there to catch a movie or documentary.The movie room with seating for plentyBut if you're an athletic person, this is your place, the gym!
It's a little bit small, but if you think we're in the middle of the ocean, the luxury of having some equipment must be appreciated.
The gym ... be careful when the ship is moving!So, there is a treadmill, some free weights, etc. Be aware of the pitch, roll and heave! These are the movements made by the ship.  Instead of explaining them, I'll post an image which can perfectly illustrate what I'm trying to say.
The differences between pitching, rolling, and heavingFor those who appreciate an indoor sport, we also have a ping-pong table. It's located one level below the Galley, at the Main Deck. I didn't use this table either, but I'll launch a challenge: Try to play ping-pong during rough seas! Imagine how cool a ping-pong game is inside a ship facing waves of 5 or 7m (or even higher).
The ping pong table ... this could get interesting in rough seasThank you...or should I say Obrigado?

João (John) Pedro T. Zielinski
Complutense University of Madrid/Federal University of Santa Catarina

The beginning of the "No Mores"

Mapping the Galicia Rift off Spain - Fri, 07/26/2013 - 11:18
Today marks the final day before we start the infamous "No Mores".  No more Saturdays, then no more Sundays, and on and on until it is time for us to set a course towards dry land.  With almost two weeks behind us on this second half of the cruise we have only a handful of sail lines left to complete (see figure below).  Once we finish the lines we will head back down to the bottom half of our work site to fill in holes; isolated spots where we were unable to collect data due to strong currents or short-lived equipment problems.  After that it's back to port where we will wave farewell to the R/V Langseth as it steams towards the waters offshore of Iceland for another scientific adventure.
Don't forget to check out our progress as we fill in the sail lines here

Happy TGIF!

Natalie Accardo
Lamont-Doherty

Step into our Office: A tour of the main science lab in the R/V Langseth

Mapping the Galicia Rift off Spain - Tue, 07/23/2013 - 08:32
A panorama view of the main science labWe left off last time with a tour of our sleeping quarters thus it seems only appropriate to now walk through the room where we spend most of waking hours; the main science lab.   Located one level below the gun deck, the main lab operates 24 hours a day controlling every aspect of data acquisition from monitoring the multichannel streamers and air-gun arrays to building the computers needed to process the terabytes of data that barrel in.  An up close view of the numerous computer screens in the main labIt can safely be said that when acquiring 3D seismic data during which approximately 6.5 terabytes of raw data will be recorded over 43 days you can never have enough computers.  In the main lab, laptops and computers occupy every surface.  Stand-alone computer monitors duck taped onto desks sit next to laptops anchored by bungee cables.  Power cords, Ethernet cables, and USB connections snake across tables in every direction periodically diving down into a dark power outlet. A bank of computer screens approximately 12 monitors wide and 3 monitors tall encircles nearly half of the lab.  These screens (39 in total) act as terminals that allow us to monitor and control a myriad of processes that are summarized in the image below.  Possibly of greatest importance are the terminals dedicated to “driving the ship.”   We aim to always have the four streamers following in perfect straight lines behind the ship however, cross-currents make this is a difficult charge.  Given the length of 6 km (3.7 miles!) and the weight of the streamers, it is akin to a toy boat towing four 23 m (75 ft) fishing lines straight behind it on a windy day. Thus to keep the streamers in the optimum orientation with respect to our acquisition line we continuously nudge the ship north and south while pulling the heads of the streamers with us. All of the steering is done from a combination of three monitors with the use of the software package “Spectra,” which in the simplest sense determines real time data coverage given the location of the air guns and the streamers.  A labeled view of the bank of computer monitors that dominates the labOf equal importance are monitors that display the health of the four streamers and the two air-gun arrays.  We aim to keep the streamers at a constant depth relative to the air-gun arrays and also at a depth that keeps them protected from passing ship traffic.  In this part of the Atlantic fishing vessels are common and with our gear sitting kilometers behind our ship and 12 m (40 ft) beneath the sea surface one could see how a vessel might not know that it is there.  Therefore, whenever we see an approaching boat we implore them to keep a safe distance away both for the safety of their vessel and for our gear.  

The back of the lab where most of the preprocessing and quality control is done.Additionally, we use this bank of terminals to monitor for the presence of critters in the water, the weather and sea conditions, and the health of the EM122 multi-beam.  Sitting back from the semi-circle of computers is another set of desks where the we, the students and scientists, stake our claim.  Outfitted with no-slip fabric and duck tape, we have covered the back of the room with our computers, which we use for pre-processing and quality control (QC) of the incoming data. 
That about covers the main lab, they keep it pretty cold down here for the sake of the computers so I’m headed up to grab another sweatshirt before I get frost bite.  Stay warm out there!
Natalie AccardoLamont-Doherty

What a difference a month makes!

Mapping the Galicia Rift off Spain - Sat, 07/20/2013 - 12:34

For those of you who have been following our adventure here's a comparison of the sea-state. I know that the few of us who have been out here for both halves definitely appreciate the difference, and for those joining for the second half it looks like smooth seas ahead!
Also, we have now reached 10,000 page views!! So thanks Mom (and everybody else).
James Gibson Lamont-Doherty
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