The Marcus G. Langseth, a research vessel operated by Lamont-Doherty Earth Observatory, traverses the world’s oceans conducting marine seismic studies that contribute to new understanding of Earth systems. The ship typically spends half the year or more on research expeditions led by Lamont-Doherty scientists and colleagues from other research institutes.
Mentions of cruises may conjure up images of mammoth floating hotels and lounge chairs, but the cruises undertaken by earth scientists involve neither of those. Researchers who examine the seismic activity taking place beneath the sea can spend many weeks each year aboard ships deploying instruments and collecting data; these cruises often involve long days working in all manner of sea conditions.
At the American Geophysical Union (AGU) fall meeting, now taking place in San Francisco, scientists and students who use the Langseth for research expeditions, the ship’s operators and administers from Lamont-Doherty and the University-National Oceanographic Laboratory System (UNOLS), and National Science Foundation program managers, met on Dec. 8 for the Marcus Langseth Science Oversight Committee annual community meeting.
At AGU, the oversight committee’s goal was to review results of the ship’s recent expeditions and discuss future research cruises. This year, for the first time, the meeting included a young career scientists workshop, where graduate students and early career investigators who have worked aboard the Langseth gave short talks about their research. Lamont-Doherty presenters included graduate students Natalie Accardo, James Gibson and Shuoshuo Han; postdoctoral researcher Nathan Miller; associate research scientist Angela Slagle; and alum Danielle Sumy (Ph.D. ’11).
Their talks were followed by presentations by scientists on the Langseth’s recent and upcoming cruise activities. Highlights included a talk by paleoclimatologist Pratigya Polissar, who discussed his May 2012 cruise near the Line Islands in the central equatorial Pacific. Scientists on this cruise collected nearly 500 feet of sediment cores, which are being analyzed and used to gain new insight into the alternating El Niño and La Niña weather patterns that affect much of the globe. The oldest core recovered on Polissar’s expedition dates back more than 400,000 years, covering the last three glacial cycles.
Marine geophysicist Fernando Martinez (Ph.D. ’88) from the University of Hawai’i at Manoa reported on a cruise that he led to the Reykjanes Ridge in the North Atlantic Ocean in August 2013. The goal of the month-long cruise was to collect multibeam, magnetics and gravity data that will inform understanding of the evolution of the Reykjanes Ridge, a segment of the Mid-Atlantic Ridge just south of Iceland. This data will be used to test competing theories about what’s happening in this geologically fascinating area, with important implications for our understanding of geodynamic processes in the Earth.
Marine geophysicist Donna Shillington described a new research initiative that will use the Langseth to acquire large geophysical datasets in Atlantic waters as part of the Geodynamic Processes at Rifting and Subducting Margins (GeoPRISMS) project. The ultimate goal of GeoPRIMS is to investigate the coupled geodynamics, earth surface processes and climate interactions that build and modify continental margins over a wide range of timescales. The data Shillington and her group obtain during an upcoming cruise aboard the Langseth will be made available to the scientific community for various studies of the deep structure of the Eastern North Atlantic Margin. The project is also unique in that it features a large education and outreach component, which will train students and early career scientists to acquire and analyze seismic data.
The Langseth is scheduled to undergo maintenance in early 2014 before spending the remainder of the year on expeditions in the North Atlantic, including the GeoPRISMS cruise.
Visit the Marine Operations section of the Lamont-Doherty website to learn more about the R/V Langseth and the Observatory’s long history of seagoing exploration and discovery.
(Updated Dec. 10, 2013. James Hansen’s Frontiers of Geophysics talk has been RESCHEDULED to Wednesday, Dec. 11)
Scientists from Columbia University’s Earth Institute will present important research results and special events at the Dec. 9-13 San Francisco meeting of the American Geophysical Union, the world’s largest gathering of earth and space scientists. Here is a guide in rough chronological order. Unless otherwise stated, presenters are at our Lamont-Doherty Earth Observatory. Abstracts of talks and posters are on the AGU meeting program. Reporters may contact scientists directly, or press officers: Kevin Krajick, firstname.lastname@example.org 917-361-7766 or Kim Martineau, email@example.com 646-717-0134
# # # # #
The $5,000 ‘Dark Data’ Contest Award
As part of an initiative to save data in danger of dying within old floppy disks, tape drives or paper archives, judges will award a trophy and $5,000 to the team that has done the best job of finding and preserving such “dark data.” The International Data Rescue Competition is sponsored by Lamont-Doherty Earth Observatory’s Integrated Earth Data Applications project (which works to preserve dark data), and scientific publisher Elsevier. Sixteen teams from across the world have submitted entries. One group of seismologists has digitized Soviet magnetic recordings of Cold War nuclear tests in hopes of improving modern test-verification procedures. Another is a volunteer group that is digitizing handwritten weather observations from ship logs dating back hundreds of years.
Dark Data Talk: Monday, Dec. 9, 10:50-11:05 a.m., 2020 Moscone West. IN12A-03.
Award Ceremony: Monday, Dec. 9, 7-8:30 p.m., Twin Peaks Room, Intercontinental Hotel, 888 Howard St.
International Data Rescue Competition website and submissions
Drying of the Mediterranean and Mideast
Richard Seager firstname.lastname@example.org
Nations surrounding the Mediterranean have been getting drier in the last decades, bringing record droughts to some places. Seager, a climate modeler, links drying in North Africa and Europe mainly to natural variability—but says there is evidence that drying of the Mideast is linked to overall climate warming. Further, based on changes in atmospheric circulation over the Mediterranean, he projects that the entire region from Spain through the Mideast may suffer increasing aridity in coming decades. This could happen not only during the usually dry summer, but during the crucial wintertime, when most rains now come in many places.
Monday, Dec. 9, 11:50 a.m.-12:05 p.m., 3003 Moscone West. GC12A-06 (Invited)
Climate Change: Spark of the Syrian Civil War?
Colin Kelley email@example.com
From 2005-2010, Syria suffered its worst drought on record. Kelley and four colleagues say that natural weather variability played a role, but the root cause was probably a long-term shift in rainfall and heat caused by human greenhouse gas emissions. They say long-term atmospheric circulation changes increased the likelihood of drought in 2011 eight times over—and that increased warmth itself has directly caused drying of soils. While the causes of the war itself are complex, the drought brought food shortages, unemployment and disruption of rural social structures, driving some 1.5 million refugees from the countryside to the peripheries of cities, where discontent exploded into the ongoing bloodbath.
Monday, Dec. 9, 1:40-6 p.m., Posters A-C Moscone South. GC13A-1047
Global Farm Yields, Future Climate, and Conflict
More researchers are exploring the potential for swings in weather and climate to drive armed conflicts, often through crop failures that lead to violence. Looking at data from 1961-2008, Rising and Cane find that during times of high crop yields, conflicts have been less likely to break out. They plan to use this baseline information, along with data on crop varieties that grow in varying conditions, future climate scenarios, and economic and political conditions, to project future conflicts in different parts of the globe.
Monday, Dec. 9, 1:40-6 p.m., Posters A-C Moscone South. GC13B-1069
(Related: Growing Susceptibility of the Global Food-Trade Network to Climate. Michael Puma, firstname.lastname@example.org. Monday, Dec. 9, 8 a.m.-12:20 p.m., Posters A-C Moscone South. GC11D-1038)
Scientists, Activism and the Impacts of Climate Change
James Hansen email@example.com
James Hansen, the outspoken former director of the NASA Goddard Institute for Space Studies, now leads a new policy-oriented climate-change program at the Earth Institute. Known for his efforts to turn science into action, he and colleagues recently made headlines with a study contending that the Intergovernmental Panel on Climate Change has vastly underestimated how quickly CO2 emissions must be slowed. Hansen will give three high-profile talks. On Tuesday, he presents the Union Frontiers of Geophysics lecture. On Thursday, he will speak on “Minimizing Irreversible Impacts of Human-Made Climate Change.” On Friday, his talk challenges the research community on “Communicating the Need to Avoid Dangerous Climate Change.” Among other things, he will discuss his past, present and planned efforts to get information to the public and to the highest levels of government.
RESCHEDULED TO: Wednesday, Dec. 11, 12:30-1:30 p.m., Hall E 134-135 Moscone North. U22C (Union Lecture)
Thursday, Dec. 12, 5:30-6 p.m., 104 Moscone South. GC44A-06 (Invited)
Friday, Dec. 13, 11:35 a.m.-12:05 p.m., 102 Moscone South. U52A-04
Climate Models! The Pinup Calendar
Co-creators: Rebecca Fowler firstname.lastname@example.org
Francesco Fiondella (International Research Institute for Climate and Society) email@example.com
Now you no longer have to dig through boring journal papers to learn all about your favorite climate scientists; just feast your eyes on the new 2014 Climate Models Calendar. Eye-popping portraits of 13 top Columbia University climate researchers in full regalia amid their natural habitat were conceived by bestselling photographer Jordan Matter (Dancers Among Us) and shot by fashion portraitist Charlie Naebeck. Calendar includes tasty inside info on the researcher of the month, such as favorite dataset or climate phenomenon. Individual dates are marked with famous climate/weather events, scientific meetings and other useful items. (There are 13 models because January 2015 comes as a bonus.) Models will be on hand to autograph calendars. (On sale through the Climate Models Calendar website, and at the Columbia M.A. in Climate and Society Program booth, no. 1329 in the Exhibit Hall.
Tuesday, Dec. 10, 1:40-6 p.m., Posters A-C Moscone South. ED23B-0725
Did a 6th Century Comet Bring Global Famine?
Dallas Abbott, firstname.lastname@example.org
Evidence from tree rings and ice cores suggest that parts of Europe, Asia and North America saw protracted cooling in the 530s, which has been linked to drought and famine. Some scientists hypothesize that Halley’s Comet may have caused this, by leaving a dust trail that the Earth later intercepted during its orbit. Dust in the air could have blocked the sun’s rays. Abbott finds evidence in ice cores drilled from Greenland: as much as 10 times more dust is found in the layer corresponding to 533 A.D. than at other intervals, she says. This dust is rich in markers of extraterrestrial origins such as nickel and iron oxide spherules. She finds that neither volcanism nor solar cycles can fully explain the cooling seen in various records during this decade. Furthermore, spikes of the ice-core dust appear to match the timing of the Eta Aquarid meteor shower, known to be triggered by Halley.
Wednesday, Dec. 11, 8 a.m.-12:20 p.m., Posters A-C Moscone South. PP31B-1869
Burying CO2 in the Newark Basin: Are There Earthquake Risks?
Natalia Zakharova email@example.com
In 2011, a consortium drilled a 1.5-mile deep hole off the New York State Thruway to study the rocks of the Newark Basin, which underlie parts of New York, New Jersey and Pennsylvania. Their goal: to understand the potential to store industrial carbon emissions, and the possible stresses on earthquake faults. Scientists are now analyzing data from this, and a second hole drilled this summer on the campus of nearby Lamont-Doherty Earth Observatory. Zakharova presents early results from the Thruway borehole; these suggest that shallow reservoirs contain critically stressed faults and are not good for injection; injecting fluids 1.2 kilometers or below may be safer.
Wednesday, Dec. 11, 1:40-6 p.m., Posters A-C Moscone South. S33D-2472
Bangladesh: Shaking and Sinking
Michael Steckler firstname.lastname@example.org
For the past four years, a team from several universities has been studying the intertwined natural hazards of earthquakes, sea-level rise and sudden changes in river courses in Bangladesh, earth’s most densely populated nation. Now, detailed portraits of the forces driving these hazards are emerging. Principal investigator Michael Steckler gives an overview of how yearly loads of Himalayan sediment and water are interacting with rising sea level and a maze of underlying tectonic boundaries to create a system of dangers that could be set off by any number of triggers. Posters in a separate session paint a picture of hidden active faults around the capital of Dhaka, and how the delta on which Bangladesh sits is being twisted and squeezed by moving watery sediments and tectonic boundaries.
Wednesday, Dec. 11, 1:40-1:55 p.m., 2005 Moscone West. EP33D-01 (Invited)
Related posters: Monday, Dec. 9, 1:40-6 p.m., Posters A-C Moscone South. T13D-2565 & T13D-2567
Megadroughts: Signposts of the Past
Benjamin Cook email@example.com
Edward Cook firstname.lastname@example.org
Dendrochronologist Edward Cook has documented drought history in North America, monsoon Asia, and parts of Europe, North Africa and the Mideast. Tree rings going back many centuries before instrumental records reveal megadroughts covering vast regions and sometimes lasting more than 100 years—greater than anything seen in modern times. Such droughts were more common in the naturally warm period 600 to 1,000 years ago, he says. This suggests that greater warmth can push large climate systems into long-term aridity, raising the specter of megadroughts in the near future as climate warms. In a related talk, climate modeler Benjamin Cook (Edward’s son) delves into North America, starting with the devastating pan-continental drought of 2012. Similar to his father, he finds that droughts like this are rare, but not unprecedented, and occur most commonly during warmer times.
Ben Cook: Monday, Dec. 9, 8 a.m.-12:20 p.m., Posters A-C, Moscone South. GC11A-0956
Ed Cook: Wednesday, Dec. 11, 4:45-5:05 p.m., 102 Moscone South. U34A-03
Turning CO2 to Stone
Juerg Matter email@example.com
Some scientists say human-induced climate change could be mitigated by pumping industrial carbon dioxide underground; however, the fear of leaks is a major stumbling block. Matter’s group has been working on ways to turn pumped-down CO2 into a harmless limestone-like solid by harnessing natural chemical reactions underground. In the first field results from a pilot injection outside Reykjavik, Iceland, they have shown that the process can indeed work. The CarbFix project is dissolving CO2 in water and pumping it 500 to 800 meters down into a formation of basalt. Chemical monitoring shows that 85% of the CO2 reacts with the basalt within a year—a rate well beyond initial expectations. Scientists continue to monitor the storage reservoir.
Thursday, Dec. 12, 8 a.m.-12:20 p.m., Posters A-C Moscone South. V41A-2753
Four scientists and one PhD student from the International Research Institute for Climate and Society (IRI) are attending the 2013 American Geophysical Union’s Fall Meeting. Below are links to Q&As with each of the presenters and the schedule of their posters and presentations. For additional information about the scientists’ work, search the conference program for their names here.
The IRI is a research center at Columbia University’s Earth Institute dedicated to enhancing society’s capability to understand, anticipate and manage the impacts of climate in order to improve human welfare and the environment, especially in developing countries.Pietro Ceccato Q&A
Poster: Development and Implementation of Flood Risk Mapping, Water Bodies Monitoring and Climate Information for Human Health (EP53A-0754)
Session: Earth and Planetary Surface Processes General Contributions Posters
Friday, Dec. 13
1:40 – 6 p.m.
Hall A-C (Moscone South)
Poster: Long-lead ENSO Predictability from CMIP5 Decadal Hindcasts (GC43D-1090)
Session: How Reliable and Accurate are CMIP5 Climate Simulations?
Thursday, Dec. 12
1:40 – 6 p.m.
Hall A-C (Moscone South)
Presentation: Climate scenarios for driving AgMIP models (GC31D-06)
Session: Improving the Understanding of climate Variability and Change in Agriculture: AgMIP, Tropical Farm Adaptation and Related Research
Wednesday, Dec. 11
9:15 – 9:30 a.m.
3001 Moscone West
Poster: Sahel rainfall variability as simulated by the CAM4 model and its associated atmospheric dynamics (A11G-0136)
Session: West African Monsoon and Its Modeling
Monday, Dec. 9
8 a.m. – 12:20 p.m.
Hall A-C (Moscone South)
Presentation: Experiences in the New York Academy of Sciences STEM Mentoring Program (PA42A-08)
Session: Communicating the Relationship Between Policy Sciences, Natural Hazards, and Global Environmental Change
Thursday, Dec. 12
12:05 – 12:20 p.m.
2020 (Moscone West)
Session (convener): Subseasonal to Seasonal Prediction: Bridging the Gap Between Weather and Climate
Monday, Dec. 9
8 – 10 a.m.
3010 (Moscone West)
Poster: Diagnostics of Interannual-to-Interdecadal Climate and Streamflow Variability: Applications to Reservoir Management over NW India (GC11A-0960)
Session: Paleoclimate, Observations, and Models: Water Resource Management Under Climate Variability and Change
Monday, Dec. 9
8 a.m. – 12:20 p.m.
Hall A-C (Moscone South)
Poster: Evaluation of Sub-monthly Forecast Skill from Global Ensemble Prediction Systems (A13E-0259)
Session: Subseasonal to Seasonal Prediction: Bridging the Gap Between Weather and Climate II Posters
Monday, Dec. 9
1:40 – 6 p.m.
Hall A-C (Moscone South)
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.
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.
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).
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.
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.
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.
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.
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.”
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.
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.
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.
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.
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
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.
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.
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 image on the left shows swath coverage. The image on the right shows an active ping through the water column.
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).
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.
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!
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.
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.
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 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.
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.
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
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.”
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.
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).
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.
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.
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
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.
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!
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
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 back of the lab where most of the preprocessing and quality control is done.