We have completed the first two stations of the OUTPACE cruise and we are steaming to Station 3. By noon tomorrow we should be in the center of an eddy that our colleagues back on dry land have used satellite data to identify. Apparently they are detecting very high chlorophyll in the center of the eddy, which should make for good sampling.
Trichodesmium is everywhere out here. I just looked out of the porthole next to the desk in my cabin, and a giant bloom was floating by on the surface of the waves. Filaments of the cyanobacterium Trichodesmium clump together and form little colonies about the size of an eyelash. When we’re on station, Andreas and I fish for colonies using a special net that we tow up and down through the water column to concentrate thousands of liters of water’s worth of biomass. It’s grueling work—I have blisters on my hands and my biceps are sore…but it makes me feel like I’m earning the five-course French meals served on this ship.
Once we’ve fished for colonies, Andi and I individually pluck out Trichodesmium colonies from amidst the other organisms that were concentrated during the tow and rinse them twice in sterile filtered seawater to remove all but the closely associated symbiotic microbes that colonize Trichodesmium. This is grueling work too, but for a very different reason than towing a net. Imagine using a tiny pipette to grab things the size of eyelashes out of water while rocking side to side on a moving ship in 90 degree Fahrenheit weather. Come visit me in the lab at Lamont and I’ll let you try and pick some Tricho—it’s hard even when the ground isn’t moving beneath you.
So far, we’ve set up experiments to look at how nutrient uptake changes when we add different microbial communication molecules to the Trichodesmium colonies we’ve plucked, and of course we’ve taken samples so I can look at the molecular underpinnings of these physiological changes. The first two stations have been pretty successful. The ship is stable enough that I haven’t had to take any Dramamine, and really, the food is incredible. I woke up to sample at 5 a.m. yesterday, buoyed by the smell of freshly baked croissants.
Now that we’ve got our sea legs, I think we’re ready for the big kahuna, so bring on whatever’s happening in that eddy!
The OUTPACE 2015 cruise has set sail on February 20! We left port in Nouméa at 8:30 a.m. last Friday morning. I lost sight of land around 10 a.m. or so, and I won’t see it again until we return to port in Papeete, Tahiti on April 3.
Preparations before departure were so hectic that I didn’t even take a moment to appreciate the last time my feet left dry land as I climbed the gangway onto the ship. I spent the majority of my last two days in New Caledonia in a nickel mine north of Nouméa with a man from Vanuatu named Lulu. One of the byproducts of nickel mining is liquid nitrogen, the ultra-cold substance used to make ice cream, slow down the Terminator, and most importantly, preserve our samples until we can analyze them back at our labs on land. There are around 30 scientists on board, and with the exception of the physical oceanographers, everyone needs liquid nitrogen. I am very thankful for Lulu, he was my escort between ship and mine as I filled dewar flask after dewar flask of liquid nitrogen, he was my translator when I thanked the miners for their time, and he very kindly obliged when I suggested that perhaps he could drive slower because the dewars are fragile and his truck had no seat belts.
Having a stockpile of liquid nitrogen is especially critical for the samples I am planning to take during the OUTPACE cruise. I mentioned before that we are interested in how communication between Trichodesmium and other bacteria influences physiology and biogeochemistry. In the Dyhrman Lab at Lamont-Doherty Earth Observatory, we go about answering these questions in part by looking at what genes these microbes turn on or off under different conditions. To do this, we sequence the RNA, or the messenger molecules that act as the intermediary between the genome and the proteins that do the work in an organism. This data provides us with a snapshot in time of every single thing the cell was doing. The unique challenge is that RNA turns over incredibly rapidly. Shortly after fishing a Trichodesmium colony out of the ocean, their RNA profile could change from representing their in situ physiology to representing the response to sudden changes in temperature, light levels or the other stresses that accompany getting jostled around in a pipette by a graduate student trying to maintain balance on a moving boat. From ocean to liquid nitrogen, I have around five minutes before the samples are ruined.
It’ll be a day and a half until I take the first sample of the cruise, however. We’re currently steaming northwest from the southernmost point of New Caledonia to our first sampling station. For now we are rehashing plans, looking at satellite data to figure out where the eddies are and the patterns in sea surface chlorophyll, and finally ensuring every single thing in the lab is secured now that there is the pitch and roll of a cruising ship.
The most astonishing thing about the universe, in my eyes,
Is not merely its gargantuan, unfathomable size,
But the way its vastness ferries gorgeous, primordial light,
So that as we look up into the night,
The farther afield our gaze penetrates, the higher we climb,
The farther we can see back in time.
Like ancient missives carefully tucked into a bottle,
Flashes of history race towards us full-throttle,
At the speed of light traversing a fabric expanding,
These waves touch our shores, and fuel our understanding
Of quasars and black holes, the light and the dark,
The Very Beginning, the bright cosmic spark
From which all this sprang – upon us, the story rains:
Of how we arose with star stuff in our veins.
Gigantic Black Hole Discovered from the Dawn of Time, National Geographic
An ultraluminous quasar with a twelve-billion-solar-mass black hole at redshift 6.30, Wu et al. (2015) Nature
This is one in a series of poems written by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory and the Department of Marine and Coastal Sciences at Rutgers University.
Scientists from research institutions around the world are participating in a research expedition aboard the R/V L ‘Atalante to study how microorganisms in the South Pacific Ocean influence the carbon cycle. Lamont-Doherty Earth Observatory graduate student Kyle Frischkorn is among them; his goal is to assess how the microorganism Trichodesmium, and other microbes, interact and the resulting physiological and biogeochemical impacts these processes have on marine ecosystems. This is the first in a series of posts in which Kyle shares what it’s like to do research at sea.
I am reporting from the shores of New Caledonia. I am just about as far away from my home in New York City as one can get—literally and metaphorically: New Caledonia is an island in the southern hemisphere, in the subtropical South Pacific, east of Australia. I am in the capital city, Nouméa, where palm trees lines streets that move at a leisurely, island pace. It’s also about 80 degrees Fahrenheit warmer than New York City right now, which is perhaps the most jarring difference of all.
Few have heard of New Caledonia, a French “special collectivity”. I hadn’t either, until I had to get a plane ticket here. During World War II this island served as the South Pacific headquarters of the US military. This was strategically important for the Allied forces during WWII, it had good infrastructure and developed roads. Additionally, the hospitality of the New Caledonians and the tropical amenities offered much needed respite for the soldiers. This is a snippet of what I learned at the Musée de la Seconde Guerre Mondiale, just one stop on my two-day exploration of the city before embarking on 45 days of non-stop science.
As luck would have it, on my way to the museum I rode the bus one stop too far—an easy mistake to make, the street signs are miniscule and in French, also the buses blast catchy, island-y remixes of American Top 40 songs so I was reluctant to disembark. After I stepped off the bus, I got my bearings and by chance found myself face to face with the research vessel L’Atalante, my home for the next 2 months.
Scientists from research institutions around the world are partaking in this expedition, the broad, overarching goal of which is to study how microorganisms in the South Pacific Ocean influence the carbon cycle. My specific project focuses on one particular microorganisms, a cyanobacterium called Trichodesmium. This microbe is important in the low nutrient, oligotrophic ocean because of their ability to take in and fix carbon dioxide through photosynthesis, and because they have the relatively rare ability to transform atmospheric nitrogen into a form that is a utilizable nutrient for other organisms in the ocean. These abilities make Trichodesmium colonies oases of biological activity in a desert-like ocean. My colleague Andreas Krupke, a post-doctoral researcher in the Van Mooy Lab at Woods Hole Oceanographic Institution, and I will be conducting a series of experiments on this transect from Nouméa, New Caledonia to Papeete, Tahiti to assess how other microbes and Trichodesmium interact and the resulting physiological and biogeochemical impacts these processes have.
Before we can get started on the science, however, the first mission is to unpack all of the gear I shipped from Lamont and re-assemble the Dyhrman Lab on L’Atalante. It’ll function just like our lab back on dry land, but all the equipment is literally tied, drilled or bungee corded to the benchtop… stay tuned!
Early winter in the Northern Hemisphere marks the start of austral summer in the Southern Hemisphere, and the beginning of the Antarctic field season. Each year, several thousand scientists head to the icy continent to take advantage of the relatively mild, though still very harsh, weather and the 24-hour daylight; the next time the sun will fall below the horizon at Antarctica’s McMurdo Station is February 20, 2015.
Lamont-Doherty Earth Observatory scientists are among the many researchers currently doing fieldwork in Antarctica. They’re leading and participating in expeditions near, above and on the continent, doing critical studies that will advance understanding of Antarctica’s land and sea processes.
Lamont biogeochemist Sonya Dyhrman is aboard an icebreaking ship, the R/V Nathaniel B. Palmer, for one month. In that time she’ll slowly travel south from Punta Arenas, Chile to research sites located off the Western Antarctic Peninsula. Dhyrman, graduate student Harriet Alexander and the other cruise scientists are investigating polar food web dynamics, with a focus on the feeding and swimming behavior of krill, a small shrimp-like crustacean. During the research cruise, Dyhrman and Alexander will collect samples of water and phytoplankton from a number of different sites. Their goal is to understand the physiological ecology of phytoplankton, which form the base of the marine food web in the Southern Ocean, and are a major source of food for krill.
More than two thousand miles south, six scientists from Lamont’s Polar Geophysics Group are at McMurdo Station, a U.S. Antarctic research center located on Ross Island. They’re deploying an ice imaging system, known as IcePod, which consists of ice-penetrating radar, infrared and visible cameras, a laser altimeter and other data-collection instruments. IcePod attaches to a New York Air National Guard LC-130 aircraft and measures, in detail, the ice surface and the ice bed; important data that enables the scientists to track changes in ice sheets and glaciers.
The scientists are testing the instrumentation and training the New York Air National Guard in the deployment and operation of the instrument; this is the first time IcePod is being used in Antarctica. After the testing and training, IcePod will be operated in up to 15 other flights for routine data collection.
Also at McMurdo Station are Lamont geologists Sidney Hemming and Trevor Williams. The two scientists and their colleagues Kathy Licht and Peter Braddock will soon fly to a field site in the remote Thomas Hills, near the Weddell Sea in the Atlantic sector of Antarctica. There they’ll spend four weeks making observations and collecting rock samples from the exposed tills on the edge of the massive Foundation Ice Stream, as well as from the Stephenson Bastion and Whichaway Nunataks.
The group is examining how ice sheets in the Weddell Sea embayment will respond to changing climate, specifically how Antarctic ice retreats and which parts of the ice sheet are most prone to retreat. Understanding the behavior of the Antarctic ice sheets and ice streams provides critical information about climate change and future sea level rise.
Thanks to the Internet and the scientists’ dedication to outreach, it’s possible to join their Antarctic expeditions without donning extreme cold weather gear. Follow the Dyhrman’s cruise activities on Twitter via @DyhrmanLab and #TeamDyhrman, and learn more about their research on the cruise website.
The first dedicated Antarctic Icepod mission was flown out across the center of the Ross Ice Shelf. Ice shelves are thick floating extensions of the ice sheet that form as the ice flows off the continent and into the surrounding ocean. These are critical ice features in Antarctica, bounding a full 44 percent of her coastline, where they serve as a buttress to slow the ice movement off the continent into the ocean.
The Ross Ice Shelf is the largest of the Antarctic ice shelves, measuring just under the size of the state of Texas. It is several hundred meters thick, although most of this is below the water surface. Along the ~ 600 kilometer front edge of the shelf, the ice towers up to 50 meters in height; a sheer vertical wall of white and the iridescent blue of compressed ice.
The goal of the six-and-a-half-hour mission was to test how the Icepod could image the varying processes at the base of the ice shelf and how well the gravimeter would work flying 90m/sec.
The gravimeter is a new addition to the Icepod suite of instruments. Housed separately inside the plane, the gravimeter requires a very stable platform. The instrument will be critical for determining the water depth beneath the Ross Ice Shelf, the least explored piece of ocean floor on our planet. The plan was to cross the front of the ice shelf towards Roosevelt Island, then fly inland until the plane crossed the J9 site where the first hole through the ice shelf was drilled in the early 1970s as part of the Ross Ice Shelf Project (RISP). Icepod would then fly back toward McMurdo along a line where there are plans for another science project to drill next year.
The collected radar data showed remarkable variability over the ice. Crossing over Roosevelt Island, the change from floating shelf ice to marginal crevasses (deep cuts or openings in the ice) to ice sitting directly on the bedrock was imaged. The variation in the reflection from the bottom of the ice probably represented the different processes occurring at the ice sheet base. In some places there was evidence of ice being added to the bottom of the shelf.
When the RISP team, which included Lamont’s Stan Jacobs, drilled through J9 in the 1970s, they found refrozen ice with a structure that resembled waffles. That team also captured pictures of fish beneath the ice shelf, demonstrating that the area below was not the wasteland that it was originally believed to be. Icepod overflew the best fishing hole on the Ross Ice Shelf while the team looked at the pictures of the bright-eyed fish in the Science paper, and smiled. It is almost 50 years later, and while we have a much better understanding of Antarctica, there remains so much that is unexplored.
Icepod and the LC-130 returned to Willie Field and began immediately to plan for the next flight.
For more on the IcePod project: http://www.ldeo.columbia.edu/res/pi/icepod/
Scientists at Columbia University’s Earth Institute will present important talks at the Dec. 15-19 meeting of the American Geophysical Union, the world’s largest gathering of earth and space scientists. Here is a journalists’ guide in rough chronological order. Unless otherwise noted, presenters are at our Lamont-Doherty Earth Observatory. Formal abstracts of all presentations are on the AGU meeting program. Reporters may contact scientists directly, or call press officers: Kevin Krajick, firstname.lastname@example.org 917-361-7766 or Kim Martineau, email@example.com 646-717-0134.
Will Rapid Global Warming Resume Soon?
Braddock Linsley firstname.lastname@example.org
Global temperatures rose quickly until about 15 years ago, and have since largely plateaued. Now, coral records from the south Pacific Ocean suggest the so-called “hiatus” may soon end. Researchers hypothesize that water in the Pacific has slowed atmospheric warming by storing excess heat generated by CO2 emissions. But when the most recent phase of the 20-some-year Pacific Decadal Oscillation comes to an end, some of this stored heat may end up back in the air. Geochemical analysis of more than 220 years of coral growth rings from the islands of Fiji, Tonga and Rarotonga adds new support to projections that the PDO will switch states within 5-10 years, triggering a new phase of rapid warming.
Monday, Dec. 15, 8 a.m.-12:20 p.m. Moscone South Posters. A11B-3017
Related: Global Heat Hiding Out in the Oceans
Frontiers of Geophysics Lecture: Jeffrey D. Sachs
Jeffrey Sachs, director of The Earth Institute, is an economist, senior United Nations advisor and best-selling author. In this headliner talk, he will speak on “The Earth Sciences in the Age of Sustainable Development.” Among other initiatives, he will discuss the Deep Decarbonization Pathways Project, a new interdisciplinary effort by scientists from the top 15 carbon-emitting nations to map specific ways each country can reorganize energy systems to limit future warming to 2 degrees C. Journalists wishing to meet with Sachs may contact press officers.
Mon. Dec. 15, 12:30-1:30 p.m., Gateway Ballroom, Moscone South
Sachs’s Earth Institute home page
Deep Decarbonization Pathways Project
Battling Epidemics With Remote Sensing
Andrew Kruczkiewicz email@example.com, Pietro Ceccato firstname.lastname@example.org (Intl. Research Institute for Climate and Society)
Remote sensing is playing a key role in showing how shifts in weather drive outbreaks of deadly diseases, and how to counteract them. Kruczkiewicz will discuss how remote sensing has linked outbreaks of leishmaniasis in Sudan and South Sudan to dryer than normal conditions during the transmission months of April-July. Imagery suggests that cracks in dried-up soil—the breeding habitat of leishmaniasis-carrying sandflies—proliferate during these months, leading to outbreaks later. Ceccato will discuss programs of The Earth Institute, City University of New York and NASA to develop practical remote-sensing tools aimed at helping African nations predict and prepare for outbreaks of leishmaniasis, as well as malaria, trypanosomiasis and schistosomiasis.
Mon. Dec. 15, 5:15-5:30 p.m., 3020 Moscone West. H14A-05
Fri. Dec. 19, 11:20-11:35 a.m., 3001 Moscone West. GC52A-05
IRI’s work on climate and health
All IRI talks at AGU
Arsenic: A Mass Poisoning In Progress
Alexander van Geen email@example.com
It could be the largest mass poisoning in history: the 1990s discovery that newly drilled wells meant to provide clean water across southeast Asia were instead poisoning 130 million people with natural arsenic. International efforts have since gone into studying the geology and hydrology of the problem, drilling wells into safer aquifers, and getting people to use them. But as van Geen reveals, many people are still exposed, for reasons that have as much to do with politics and public education as geologic conditions. Van Geen and colleagues are leaders in studying and remediating all aspects of the problem. They are now working in the United States as well, where new health studies are showing that wells laced with arsenic are affecting people in the eastern U.S. and Canada.
Tues. Dec. 16, 9:30-9:45 a.m., 2005 Moscone West. U21A-06 (Invited)
Related: Do Arsenic Concentrations in Groundwater Change Over Time? Therese Chan, Tues. Dec. 16, 1:40-6 p.m., Moscone West Posters. H23E-0921.
Columbia’s arsenic research program
Van Geen’s work in southeast Asia
Low Ground, High Risk Seismic and Flooding Threats in Bangladesh
Christopher Small firstname.lastname@example.org, Leonardo Seeber email@example.com
A five-year program has brought into focus the potential for Bangladesh, the world’s most densely populated nation, to suffer catastrophic earthquakes, tsunamis and river-course changes—possibly all at once. Seeber and Small will discuss definitive signs of previous big quakes and at least one great tsunami; hidden features under the Ganges-Brahmaputra delta that may drive these disasters; and rapidly moving urbanization that is making the risks ever greater. The evidence rests on satellite imagery, GPS measurements, seismology and sedimentology. Posters on Thursday will delve into the details of apparent past events that could now be repeated with much greater loss of life and property.
Chris Small: Tues. Dec. 16, 8:15-8:30 a.m. U21A-02 (Invited). Leonardo Seeber: Tues. Dec. 16, 9:15-9:30 a.m. U21A-05 (Invited). 2005 Moscone West. Posters: Paleoseismic Records of Earthquakes Along the Southeastern Coast of Bangladesh., T43B-4712; Evidence for Tsunami Generated by the 1762 Great Arkan Earthquake,T43B-4732. Thurs. Dec. 18, 1:40-6 p.m., Moscone South.
Short film on the project
Warmer Climate Threatens Airplane Takeoffs
Ethan Coffel firstname.lastname@example.org Radley Horton email@example.com (Center for Climate Systems Research)
Climate plays an important, underappreciated role in how much weight aircraft can safely carry at takeoff. Hot weather can reduce lift, forcing airlines to offload cargo and passengers, eating into their bottom line. In what may be the first study to look at the changing economics of flying in a warmer climate, researchers estimate that airlines flying out of four airports—Phoenix, Denver, New York’s LaGuardia and Washington D.C.’s Reagan—will see 50 percent to 200 percent more weight-restricted days in spring and summer by 2050-2070. Worldwide, airports at higher elevations and with short runways and limited room to expand will feel the impacts most. Future airplanes may have to be designed to compensate for reduced lift in the weather of the future.
Tuesday, Dec. 16, 5:30 p.m.-5:45 p.m. Marriott Marquis Salon 13-15 PA24A-07
Lamont-Doherty Earth Observatory/Environmental Sciences Party
More info: Kevin Krajick firstname.lastname@example.org
Traditionally on Tuesday night at AGU, Lamont-Doherty Earth Observatory and Columbia’s Department of Earth and Environmental Sciences gather staff scientists and the many alumni who have since gone on to other institutions worldwide. It is a great opportunity to make acquaintances, hear informally about the latest ideas and work, and have fun. All journalists covering AGU are welcome.
Tues. Dec. 16, 6:30 p.m.-8:30 p.m. (or beyond), San Francisco Marriott Union Square, 480 Sutter Street, Union Square Ballroom
Mapping Defenses Against Urban Heat Waves
Alex de Sherbinin email@example.com (Center for International Earth Science Information Network)
Already vulnerable to heat waves, city dwellers face greater risks as the planet warms. In Philadelphia, where this is already evident, geographers have combined multiple data sets to pinpoint where higher temperatures, less vegetation and a concentration of poor or elderly puts people most at risk. The map is aimed at helping the city plant trees and vegetation where needed (including on rooftops), help social workers respond, and provide other defenses. In 1980-2013, the average number of heat-wave days per year here grew from 4 to 12, largely because streets and buildings trap heat, and there are fewer trees.
Friday, Dec. 19, 8 a.m.-12:20 p.m., Moscone West Posters. GC51B-0417
Using Submarines to Chart Arctic Ocean Conditions
Raymond Sambrotto firstname.lastname@example.org
Since the 1990s, U.S. Navy subs cruising under Arctic Ocean ice have produced seminal data not available by other means, including measurements of thinning sea ice. The program, dubbed SCICEX, was recently expanded to sample water temperature, chemistry and biology. Sambrotto presents the latest data from the remote western Arctic, gathered in spring 2014. Among other things, it establishes the levels of nutrients under the ice available for biological productivity the following summer, when melting takes place—critical to understanding how ongoing dramatic changes in ice cover may affect Arctic ecology.
Fri. Dec. 19, 8 a.m.-12:20 p.m., Moscone West Poster Hall. OS51C-0989
Water Systems of the Future
Upmanu Lall email@example.com (Columbia Water Center)
Lall, director of the Columbia Water Center, examines currently overlooked opportunities to redesign water systems to meet rising demand and declining supply. He envisions a new world in which water is treated exquisitely, like a crop of expensive vegetables, for consumption. This would include sophisticated systems to harvest rainwater; new technologies to recycle wastewater; and sensors and smart grids to monitor and manage usage in communities and buildings. He will discuss the technological, financial and social barriers that need to be overcome, and ways to accomplish that. Other talks from the Water Center during the week will cover studies of flooding in rivers from the Hudson to the Danube; newly launched satellite tools to survey global surface moisture; and the operation of China’s Three Gorges Dam.
Fri. Dec. 19, 10:35-10:50 a.m., 2009 Moscone West.
All Columbia Water Center talks
# # # # #
The Earth Institute, Columbia University, mobilizes the sciences, education and public policy to achieve a sustainable earth. Researchers at our following centers are presenting at AGU:
Lamont-Doherty Earth Observatory is one of the world’s leading research centers. It seeks fundamental knowledge about the origin, evolution and future of the natural world. More than 300 research scientists study the planet from its deepest interior to the outer reaches of its atmosphere, on every continent and in every ocean.
The International Research Institute for Climate and Society aims to enhance society’s ability to manage the impact of seasonal climate fluctuations. From environmental monitoring and forecasting to risk management tools in water resources, public health, agriculture and food security, IRI and its partners focus on opportunities to build capacity for bringing climate information into regional planning and decision-making.
Goddard Institute for Space Studies, an affiliate of The Earth Institute, is a NASA-based climate research center that models and monitors earth systems, to predict atmospheric and climate changes. It also plays an important teaching role, conducting science education programs at universities, schools and other organizations.
The Center for International Earth Science Information Network (CIESIN) works at the intersection of social, natural and information sciences. It specializes in spatial data integration, and interdisciplinary research related to human interactions in the environment, providing data that informs decision-makers worldwide. .
The Columbia Water Center tackles the issue of freshwater scarcity through innovations in technology, public policy and private action. Combining scientific research with policy, it aims to design reliable, sustainable models of water management on local, regional and global levels.
This blog is an outgrowth of my own research examining the past temperature of Earth’s surface and the relationship of temperature to the Earth’s carbon system. I became interested in the scientific aspects of this work as a geology undergraduate, staring at regular layers of rocks in the countryside of central Italy, back and forth, dark and light. These layers were related to past oscillations of the climate, warmer and cooler, related to long-term changes in the incoming solar radiation entering our planet from the sun. Such changes are small, but positive and negative feedbacks in the Earth system interact to translate the small changes into the radically layered rocks we see in outcrops. This was the start of a journey of discovery that continues to this day and is the foundation of my research at the Lamont-Doherty Earth Observatory.
How does the carbon dioxide (CO2) content of the atmosphere influence climate? This question was first seriously considered in the mid- to late-1800s, amid an accelerating, newfound interest in the natural sciences on the European continent. Specifically, the Victorians were fascinated by looking backward in time, at periodic extreme cold spells, also known as ice ages, when glaciers as tall as skyscrapers covered vast areas of land that today are free from ice.
The discourse about past climates began with this approach, through a discussion about how the driving forces in the Earth system might have caused our globe to periodically enter and exit the ice ages. Many factors, including emissions from volcanoes, the rearrangement of continents, the evolution of plants and vegetation, solar sun-spot cycles, and even asteroid impacts can and do impact the average surface temperature of the planet.
Yet time and again scientists returned to the role that greenhouse gases, and specifically carbon dioxide (CO2), play in the climate system. CO2 molecules in the atmosphere absorb heat (infrared radiation) coming from the Earth’s surface and then re-radiate some of that heat back to the surface to generate a warming effect. How is this related to the glacial ice age cycles of the past?
One way to think about this problem is to imagine the Earth system as a huge, naturally occurring experiment (though the sample size by most experimental standards is low). Sometimes the Earth has been warmer than today, even ice-free at the poles. When the ice melts, sea level rises, continents spring back after being depressed by the weight of the ice, and plants that need warmer weather expand their habitat pole-ward. The Earth has also been cooler than today, most recently at the last glacial maximum (~20 thousand years ago) when more ice was locked up in the polar ice sheets rather than in the ocean, making for lower sea level, which exposed more of what is today the ocean floor.
Today the framework of thought has turned around, so that instead of looking back through time to understand the climate of the past, we also try to learn lessons from the past to further our understanding of the climate of the future. By burning fossil fuels for heating, electricity, transportation and other purposes, humans add CO2 to the atmosphere. Yet, by comparing ways in which the Earth’s temperature, CO2 concentration, sea level and ice sheets have changed in the past, we are able to learn valuable lessons about the climate system of today and tomorrow. You can share in this adventure here.
One last word of caution: At the turn of the last century, people also began to wonder if land-use and manufacturing—human-induced variability—could play a role in climate. Because this issue has become highly politicized, I won’t get into all the back-and-forth arguments here. That forum has other locations online. However, for a modern history of this fascinating topic, check out the American Institute of Physics (which can be found at http://www.aip.org/history/climate/co2.htm); and for more on the science, check out what the EPA has to say (http://www.epa.gov/climatechange/ghgemissions/gases/co2.html). Both purport an objective analysis of both the history and basic science involved.
Migrating south in the winter is a behavior that Antarctic scientists share with many species of birds, although the scientists fly just a bit further south. For the IcePod team, it was time to join the migration so they could test their equipment in the most challenging environment the Earth has to offer. After three “equipment shake down” trips to Greenland over the last two years, 20 hours of flight time have been set aside for flights in Antarctica, part of the final hurdle in the commissioning of the pod.
The team arrived early this month at McMurdo Base on a large C-17 to –14°F weather and beautiful clear blue sky as the plane touched down on the Pegasus Blue Ice Runway. The first few days were spent in training for everything from driving trucks in the cold to being environmentally sensitive to the Antarctic microbes to a crash course on interpreting the complex way trash is handled in Antarctica — an impressive 60 percent of everything is recycled.
The gear arrived soon after the team… first the gravity meter, borrowed from New Zealand, wrapped in a warm, manly pinkish quilt. With many boxes being stacked in the aircraft, the color was selected for its high visibility to assist with quick location and unloading. The IcePod and the equipment rack had paused on their trip down in Pago Pago, arriving a few days after the rest of the gear, but it was all quickly set up and humming in a bright yellow and blue rack tent next to the Willy Airfield on the Ross Ice Shelf. While waiting to fly, a GPS was installed on top of the tent, and equipment was set up to test performance. Both the GPS and the gravity meter measured the movement of the ice shelf as it shifted up and down on the tide ~ 1 meter a day. In addition to the rhythmic up/down movement, the tent, the airfield and the ice shelf are all moving northwards at 30 cm or 1 foot a day.
Finally, IcePod was cleared to fly and complete her first Antarctic survey mission installed on a Pole Tanker mission flying on Skier 95. The flight was delayed as the C-17 practiced airdrops over the South Pole runway, but as soon as the C-17 was out of the way, icePod took off and headed south.
Low elevation data was collected on the way out to make sure the C-17 was clear. All the instruments worked in the flight across the very flat Ross Ice Shelf, then over the Transantarctic Mountains and across the spectacular East Antarctic Ice Sheet.
The low angle of the sun made the mountains, crevasses and wind scour areas stand out beautifully in the imagery. The deep radar imaged the structure of the Ross Ice Shelf even from 21,000 feet. The infra-red camera showed the variable temperature of the different types of ice in the Beardmore Glacier and the high plateau. The gravity meter that had rolled in on the speed pallet was extremely stable. At the South Pole, Skier 95 offloaded fuel while the IcePod team made a quick trip to the actual pole.
The flight was a success – data collected on an opportune flight and fuel delivered.
For more on the IcePod project: http://www.ldeo.columbia.edu/res/pi/icepod/
There once was the Langseth, a ship
Over wave and trough did she skip.
Many instruments aboard
To always record
Depth, gravity, mag – every blip.
There once was the Langseth, a vessel
Where in their bunks scientists nestled.
‘Til called to their shifts
Their heads they must lift
For with errors and logs they must wrestle.
There once was the Langseth, a boat
On her airguns the crew they would dote.
Oft while in a turn
Guns were brought up astern
To ensure best acoustical note.
There once was the Langseth, seacraft.
Where we launched XBTs down a shaft.
With each probe descent
To the lab data went
So that temperature-depth could be graphed.
There once was the Langseth, a fine tub!
Where the galley crew made us good grub.
But when seas ran high
Up in knots stomachs tied
And to keep the food down, there’s the rub.
There once was the Langseth, fair barge.
To collect seismic data her charge.
Streamer 8-km long
And four gun strings strong
She’s the fleet’s seismic dreadnaught at large!
-Tanya Blacic, aboard the R/V Marcus. G. Langseth
Time series of deployment and recovery. Photo Credit: Ernie Aaron.~Ernie
It takes a team of people to get the OBS in the water and back out again. To illustrate the process of deploying a WHOI or SIO OBS, Gary Linkevich has created a time lapse video. The first part of the video captures two WHOI OBS deployments with Peter, Dave, Dylan, Gary, and Kate. The WHOI OBS are the peanut shaped yellow capsules that appear in the background next to the railing. After the WHOI OBS is in the water, we capture an SIO OBS deployment with Mark, Dylan, Gary and Kate. The SIO OBS are the rectangles with a yellow top and white base. Right after we deploy the SIO OBS, we start putting together a new one for deployment. The assembly process involves an instrument test and then attachment of the metal weight, floatation devices, light, and radio together. The deployment of this SIO OBS happened during the midnight crew shift which includes Ernie, Pamela, Afshin and Jenny. Once they pick her up and put her in, they start the assembly process all over again!
Thanks Gary for putting together this time lapse!
See you Later,
Kate Volk aboard the R/V Endeavor
One of our assistant engineer, Kurt Rethorn, gave us a tour of the engine room. Here's what we learned:
Kurt is an awesome tour guide!
Water quality (Photo credit: Kate Volk)Sea water temperatures in the Gulf Stream are pretty warm (Photo credit: Kate Volk)
Tropical mountain ranges erode quickly, as heavy year-round rains feed raging rivers and trigger huge, fast-moving landslides. Rapid erosion produces rugged terrain, with steep rivers running through deep valleys. However, in a number of tropical mountain ranges, landscapes with deep, steep valleys transition quickly into landscapes with low-sloping streams and gentle slopes at high elevations. This topographic contrast between high and low elevations poses a problem for geologists. Though heavy rains fall throughout the mountain range, erosion seems to sculpt parts of the mountain differently from others.
Mount Chirripó, Costa Rica’s highest peak, bears exactly this type of terrain, with flat valleys at high elevation capping rugged valleys below. The beveled summit of Mount Chirripó bears striking resemblance to summits as far away as Taiwan, Papua New Guinea and Uganda. Some geologists think that tectonic forces deep below earth’s surface pushed Chirripó into its flat-topped form about 2.5 million years ago. Others think glaciers did the work, sculpting the peak in over hundreds of thousands of years.
Max Cunningham, a graduate student at Columbia University’s Lamont-Doherty Earth Observatory, traveled to Chirripó this past summer to test the idea that mountain glaciers carved the summit we see today. Working with his adviser Colin Stark, a geomorphologist, and Michael Kaplan, a geochemist, both at Lamont-Doherty, Cunningham chiseled away samples of glacial debris to take home for analysis. The researchers hope to eventually pin down when the high-elevation valleys capping Mount Chirripó’s summit eroded into their current form. Read more about their work in the above slideshow.
Photos by Max Cunningham unless otherwise credited.
It was nearing time to launch the next expendable bathythermograph probe, or XBT. The software was readied and two scientists headed out of the lab, radio in hand. They donned lifejackets that had once been bright orange but were now closer to a dull rust color from long and dirty use on the deck and selected a T-5 probe from the box.
Out on the deck they were alone, perched partway up the stack of levels in the stern of the ship, the gun deck below them and the paravane deck above. It seemed that the others working the graveyard shift were all inside, perhaps wrestling with some mechanical puzzle or else simply keeping watch to make sure all was well, sipping strong coffee, playing cards to pass the time. The scientists snapped the probe into the gun-shaped launcher. They removed the plastic end cap from the black cylinder that housed the probe and its spool of fine copper wire.
“We’re in position.”
There was a pause, then the radio crackled back, “Launch probe.”
In a moment the probe was sliding down the long tube that extended out and downward from the starboard side. With a small splash it plunged from the end of the tube into the inky deep. Now to wait while it made its journey towards the bottom, more than 4000 meters below. Despite the very late (or very early, depending on your point of view) hour, it was warm. The air was muggy – not exactly a welcome change from the air-conditioned lab, although the tinge of diesel fumes was less out here in the relative open. There was little wind and the seas were calm. Standing on the moving island of light that was the ship the sea quickly disappeared into the surrounding void. What surface that could be seen appeared to rise disturbingly close up alongside them, like a churning wall of water. It was only visible at all by the few swirls of foam formed by the ship’s passage and a reflection here and there off the constantly moving face of the black oily-looking water. They waited for the go ahead to terminate the probe.
Down in the lab, there was a strange blip on the screen showing the multibeam bathymetry data, but no one noticed as they were too busy entering in location data for the XBT or scrutinizing the movement of the streamer birds that regulated the depth of the hydrophone streamer. There were, after all, 36 other monitor screens to watch.
Outside there was a louder than usual splash. The two scientists peered into the gloom.
“Dolphin?” one wondered out loud.
“While we’re shooting? I hope not,” the other replied, “We’ll end up having to interrupt the line.”
Was there something just under the water surface? A pale sinuous shape at the very edge of the ship’s halo of light? No, it must be a trick of the light and the weird perspective engendered by the lack of any sense of distance. Perhaps more coffee was in order when they got back inside.
The radio crackled again, “Terminate probe.”
The scientists broke the wire that was still spooling out to the probe that was now falling behind them. “Probe terminated,” they reported. They were just turning to leave when it emerged.
At first it looked like a whale back, though pale milky green in color rather than the expected grey. As it lifted free from the surface it became clear that it was much longer than an orca or even a grey whale, more like an ancient marble column turned soft and rubbery. It tapered as more of its length was exposed until the tip broke free of the clinging water. One side of the enormous snake-like shape was covered with round suckers the size of dinner plates in a poisonous green color. The cyclopean tentacle towered out of the water, waving gently with a sickening sort of grace ten meters or more above the uppermost deck. Here and there along its length were clots of a coppery tangled substance, almost like seaweed wrapped around it. “The XBT wire,” one of the scientists realized from the midst of her fascinated horror.
The tentacle hovered for another movement before swooping down with surprising swiftness. The two scientists were neatly plucked from the ship in the blink of an eye. With a clatter, the radio fell to the deck. They were held above the water for a long moment, crushed together so tightly they couldn’t speak and could barely draw breath. Then, slowly, the tentacle disappeared beneath the smoothly rolling waves.
Two hundred and sixty-seven shots until the next XBT.
-by Tanya Blacic aboard the R/V Langseth (with a wink to H. P. Lovecraft)