Reports that a portion of the West Antarctic Ice Sheet has begun to irretrievably collapse, threatening a 4-foot rise in sea levels over the next couple of centuries, surged through the news media last week. But many are asking if even this dramatic news will alter the policy conversation over what to do about climate change.
Glaciers like the ones that were the focus of two new studies move at, well, a glacial pace. Researchers are used to contemplating changes that happen over many thousands of years.
This time, however, we’re talking hundreds of years, perhaps — something that can be understood in comparison to recent history, a timescale of several human generations. In that time, the papers’ authors suggest, melting ice could raise sea levels enough to inundate or at least threaten the shorelines where tens of millions of people live.
“The high-resolution records that we’re getting and the high-resolution models we’re able to make now are sort of moving the questions a little bit closer into human, understandable time frames,” said Kirsty Tinto, a researcher from Lamont-Doherty Earth Observatory who has spent a decade studying the Antarctic.
“We’re still not saying things are going to happen this year or next year. But it’s easier to grasp [a couple of hundred years] than the time scales we’re used to looking at.”
The authors of two papers published last week looked at a set of glaciers that slide down into the Amundsen Sea from a huge ice sheet in West Antarctica, which researchers for years have suspected may be nearing an “unstable” state that would lead to its collapse. The West Antarctic Ice Sheet is mostly grounded on land that is below sea level (the much larger ice sheet covering East Antarctica sits mostly on land above sea level).
Advances in radar and other scanning technologies have allowed researchers to build a detailed picture of the topography underlying these glaciers, and to better understand the dynamics of how the ice behaves. Where the forward, bottom edge of the ice meets the land is called the grounding line. Friction between the ice and the land holds back the glacier, slowing its progress to the ocean. Beyond that line, however, the ice floats on the sea surface, where it is exposed to warmer ocean water that melts and thins these shelves of ice. As the ice shelves thin and lose mass, they have less ability to hold back the glacier.
What researchers are finding now is that some of these enormous glaciers have become unhinged from the land – ice has melted back from earlier grounding lines and into deeper basins, losing its anchor on the bottom, exposing more ice to the warmer ocean water and accelerating the melting.
In their paper published in Geophysical Research Letters, Eric Rignot and colleagues from the University of California, Irvine, and NASA’s Jet Propulsion Laboratory in Pasadena, Calif., described the “rapid retreat” of several major glaciers over the past two decades, including the Pine Island, Thwaites, Haynes, Smith and Kohler glaciers.
“We find no major bed obstacle upstream of the 2011 grounding lines that would prevent further retreat of the grounding lines farther south,” they write. “We conclude that this sector of West Antarctica is undergoing a marine ice sheet instability that will significantly contribute to sea level rise in decades to come.”
The region studied holds enough ice to raise sea levels by about 4 feet (Pine Island Glacier alone covers about 62,000 square miles, larger than Florida). If the whole West Antarctic Ice Sheet were to melt, it could raise the oceans about 16 feet.
In the second paper, Ian Joughlin and colleagues from the University of Washington used models to investigate whether the Thwaites and Haynes glaciers, which together are a major contributor to sea level change, were indeed on their way to collapsing. “The simulations indicate that early-stage collapse has begun,” they said. How long that would take varies with different simulations – from 200 to 900 years.
“All of our simulations show it will retreat at less than a millimeter of sea level rise per year for a couple of hundred years, and then, boom, it just starts to really go,” Joughin said in a news release from the University of Washington.
Many scientists who’ve been studying the region were already braced for the storm.
“It’s gone over the tipping point, and there’s no coming back,” said Jim Cochran, another Lamont researcher with experience in the Antarctic. “This … confirms what we’ve been thinking for quite a while.”
Cochran is principal lead investigator for Columbia University in Ice Bridge, the NASA-directed program that sends scientists to Antarctica and Greenland to study ice sheets, ice shelves and sea ice using airborne surveys. Much of the data used in the new papers came from the Ice Bridge project.
Tinto, also an Ice Bridge veteran, agreed. “I thought it was pretty exciting, because we’ve all been working on this area for a long time, and that potential for the West Antarctic Ice Sheet to behave in this way, we’ve been aware of it for a long time,” she said. “[It] made me want to get in there and look at the rest of the area, what else is going on.”
And there are still many questions about what’s going on: How fast the ocean that swirls around Antarctica is warming, how those ocean currents shift, and to what extent that is influenced by global warming.
“I have a problem with the widespread implication (in the popular press) that the West Antarctic collapse can be attributed to anthropogenic climate change,” said Mike Wolovik, a graduate researcher at Lamont-Doherty who studies ice sheet dynamics. “The marine ice sheet instability is an inherent part of ice sheet dynamics that doesn’t require any human forcing to operate. When the papers say that collapse is underway, and likely to last for several hundred years, that’s a reasonable and plausible conclusion.”
But, he said, the link between CO2 levels and the loss of ice in West Antarctica “is pretty tenuous.” The upwelling of warmer waters that melt the ice has been tied to stronger westerly winds around Antarctica, which have been linked to a stronger air pressure difference between the polar latitudes and the mid-latitudes, which have in turn been linked to global warming.
“I’m not an atmospheric scientist, so I can’t evaluate the strength of all of those linkages,” Wolovik said. “However, it’s a lot of linkages.” And that leaves a lot of room for uncertainty about what’s actually causing the collapse of the glaciers, he said.
Researchers have been discussing the theory of how marine ice sheets become unstable for many years, said Stan Jacobs, an oceanographer at Lamont-Doherty who has studied ocean currents and their impact on ice shelves for several decades.
“Some of us are a bit wary of indications that substantial new ground has been broken” by the two new papers, Jacobs said. While ocean temperatures seem to be the main cause of the West Antarctic ice retreat, there’s a lot of variability in how heat is transported around the ocean in the region, and it’s unclear what’s driving that, he said. And, he’s skeptical that modeling the system at this point can accurately predict the timing of the ice’s retreat.
But, he added, “this is one more message indicating that a substantial sea level rise from continued melting of the West Antarctic Ice Sheet could occur in the foreseeable future. In the absence of serious near-term greenhouse gas mitigation efforts, such as an escalating tax on carbon, they may well be right.”
“It starts bringing it a little closer to home,” said Tinto. “It’s a significant amount of change, but something we can start planning for. Hopefully [this will] make people stop procrastinating and start planning for it.”
Cochran agreed: The papers’ message is “that … over the next couple hundred years, there’s going to be a significant rise in sea level, and at this point we can’t stop it.” But, he added, “it doesn’t say give up on trying to cut emissions. … [Just] don’t buy land in Florida.”
For further details on what’s going on in West Antarctica, check out these resources:
- A NASA primer on the West Antarctic Ice Sheet
- Images and video on Antarctica from NASA
- J Farmer’s Almanac: an explanation of the studies by Jesse Farmer, a PhD student in the Department of Earth and Environmental Sciences at Columbia University.
- An explanation on the Antarctic Glaciers.org site
- More on the Ice Bridge program
The two papers in question:
Widespread, rapid grounding line retreat of Pine Island, Thwaites, Smith and Kohler glaciers, West Antarctica from 1992 to 2011, E. Rignot, J. Mouginot, M. Morlighem, H. Seroussi, B. Scheuchl, Geophysical Research Letters (2014)
Marine Ice Sheet Collapse Potentially Underway for the Thwaites Glacier Basin, West Antarctica, Ian Joughin, Benjamin E. Smith, Brooke Medley, Science (2014)
Armin Van Buuren, Ancient Wood, and Ghengis Khan: This is not your father’s field research in Mongolia
We never expected this. Enkhbat had us hovering at warp speed along the Millennium Road in the northern shadows of the Khangai Mountains. Armin Van Buuren’s A State of Trance filling our rig. We were starting a new project to study the interaction between climate, fire, and forest history in the land of Chinggis Khaan and a silky voice was lifting us higher, “and if you only knew, just how much the Sun needs you, to help him light the sky, you’d be surprised. Do…do…do.do”. We were exhilarated. The Sun was shining. This was not exactly Chinggis’ steppe. But little did we know, we would eventually be chasing his ghost.
Byarbaatar & Amy in front of Khorgo, unknowingly about to meet Chinggis’s ghost. Photo credit: Enkhbat.
After about a day’s travel we started passing the Khorgo lava field. Amy asked, “What’s that?” Neil had forgotten about this landmark despite having walked upon it 10 years prior. It is a ~30 km2 lava field with old trees on it. Gordon Jacoby, Nicole Davi, Baatarbileg Nachin, and others had sampled in the early aughts and put together a ca 700 yr long drought record from Siberian larch. Neil relayed this information to Amy and she said that we should sample on it knowing that a 2,000 yr long record in the American Southwest had been produced on a similar landscape feature. We had a tight schedule, but as we drove out to the western edge of the Khangai’s, sampled sites, witnessed a sheep in the dying throes of a brain worm infection, got snowed on, and then sweated in much warmer temperatures, we decided it was worth the time to see what was out there. Little did we know.
By the time we arrived to start sampling, Neil was getting sick (we learned days later that Neil was coming down with tonsillitis) and we were on fumes from some bone-challenging swings in the weather. Amy pushed on during the first day with Byarbaatar and Balginnyam. The found a pile of dead horse bones and couldn’t get the chainsaw running stopping them from acquiring samples from downed, dead trees. It felt almost hopeless.
We summoned our strength the next day and explored a new section of the lava field. Soon after getting out there we starting seeing Siberian pine, a tree Neil hadn’t seen on his first visit and hadn’t been sampled previously at this site. We decided that after our fire history collection we would sample some pine trees just to see what They might have to say.
The Logo Tree: The Siberian pine that clued us into the possibility that there might be something extraordinary on the Khorgo lava field. Photo credit: Amy Hessl
As this collection wasn’t priority, these samples sat until late January of the following year. Here is the first email of the discovery (partially redacted for some sensitive language).
The sample “locked in and said the inner ring i measured was 1235…whoa! that was cool b/c i started a good bit from the pith…. i race back to me scope and measuring stage…..make mistakes. going too fast. fix the mistakes…..the PITH is 1142!!!!
yes, i can see the yr Chinggis was born. i can see the yr he died. i can see the yrs Mongolia rose to rule Asia!
this has been our Holy Chinggis during the entire Mongolian project.
this is totally hot censored.
ps – i guess we are going back to Khorgo, huh?”
KLP0010a – the first sample of Siberian pine from the 2010 Khorgo lava collection to break the 1200s. The pith is 1142 CE (Common Era). Photo credit: Neil Pederson
We secured funding and we went back to Khorgo in 2012 with a bigger crew and one goal in mind – collect more wood.
We cannot believe what we have found.
For centuries, common wisdom held that the Mongols were driven to conquest because of harsh conditions – drought. Our new record, dating back with confidence to 900 CE (Common Era), indicates the opposite. After the unification of the Mongols, Chinggis Khan, you know him as Ghengis Khan, led his army from Northern China in 1211 to the Caspian Sea in 1224 CE. Our new record in PNAS indicates that it was consistently wet from 1211-1225, a period we are calling the Mongol Pluvial (look for an open access version of this paper here or contact Amy or me). No years during this period were below the long-term average, which is a singular rare run of moisture conditions in our 1,100 year long record. Independent tree-ring records over extra tropical Asia also indicate that this period was warm.
On the cool semi-arid steppe of Central Asia, water is life and in those days, water was energy. The Mongol diet is heavily based on the meat of grazers. Their mode of transportation was the short, but Pheidippidic horse. So, for food and for travel, grass is life. Grass is energy. An abundance of moisture would seem to provide the horsepower for the rapidly growing Mongol Empire. The Mongol soldier had five steed at their disposal. With a large army, that quickly translates into a huge herd and a huge need for grass.
Our tree-ring record suggests that the grasslands of central Mongolia were likely productive. They strongly agree with satellite estimates of grassland productivity. Going back in time, then, the trees would suggest the Mongol Empire during its rapid expansion was sitting in a sea of grass, a sea of energy, a potential abundance of life.
That is our hypothesis, anyhow, and something we will test in the coming years with historical documents, environmental records from lake sediments, more tree rings, and ecological modeling experiments.
While this record speaks to a rapid transformation of Eurasian culture during the 13th century, it also speaks about an abrupt transformation in Mongol culture today. Towards the end of our tree-ring record we see a prolonged drought from the end of the 20th century into the beginning of the 21st century. This drought followed the wettest century of the last 11 and occurred during the warmest period of the last 1,100 years in Asia. The abrupt transition in the environmental conditions, a transition that saw hundreds of lakes and wetlands disappear from the landscape, occurs during the transition from a more agriculturally-based economy to a more urban-based economy. These severe conditions, in combination with some harsh winters, killed millions of livestock and are thought to be one trigger of a mass migration of Mongols from the countryside into the capital of Ulaanbaatar.
Ulaanbaatar in 2006. The homes on the far hills likely reflect climatic and economic refugees moving from the countryside into the city. Photo credit: N. Pederson
Though we cannot connect this heat drought to climate change (though maybe we kind of can), warming temperatures have stacked the deck towards higher evaporative demand, so even if the amount of precipitation remains the same, high temperatures will generate a more intense drought. That’s what we observed in the early 21st century and based on past moisture variation in Mongolia and future predictions of warming, we would expect to see similar events in the future.
From Armin Van Buuren to Chinggis Khaan to Armin Van Buuren again. We had no clue of how Summer 2010 would light the sky.*
* this post was requested by a media outlet so they could have the ‘author’s voice’ on this discovery. That version was ultimately sanitized for your protection. Here it is unadultered.
To record these lower-crustal and upper-mantle phases as “first arrivals”, where they are not obscured by the arrival of energy from shallow paths, we use long lines. Long lines mean lots of receivers and lots of driving to deploy and recover these instruments. We could have used lots of sources instead, but the blasts we used to get seismic energy into the lower crust and upper mantle in this experiment take a lot of time and money to setup. Receivers are much cheaper, so we used a lot of them. (For similar wide-angle/long-offset work at sea, airgun sources are cheaper than putting seismometers on the seafloor, so we use many shots and a smaller number of receivers out there.)
South-central part of the seismic line. The yellow line is team 5's section. We have been in a relatively rural part of Georgia and as a result have not encountered many locals save a few who have stopped to ask if we are ok. However, we have seen quite a few interesting things that are quite out of the ordinary (to me at least).
Friendly Muscovy duck.Rocks in a stream bed with associated pink spongy material (?)
Spanish moss.Linguoid (current) ripples on a washed out road. We have also seen quite a few old abandoned farm houses in various stages of aging...
All said we have dug 122 holes in team 5's stretch. We have also helped deploy instruments in other sections as well and while doing so have seen others hard at work.
Meghan and Nate getting it done!Along the way the cars have taken quite a beating and have actually held up pretty well. Although there have been a few instances where people got stuck, I think that the people with the toughest job will be the guys that have to detail the cars upon their return...
A more appropriate vehicle (?)And lastly here's a couple more random pictures that I thought were interesting.
The large disparity in fuel grade gas prices.
A ~perfectly leveled geophone (it's harder than you'd think).Hopefully this random selection of pictures was entertaining. Up next we will post about last night's "shots." In the meantime, I can say that they were all successful with varying degrees of excitement. The most important thing is that all of our hard work is being realized as the instruments are recording refractions from buried geology that will help us unravel some of the mystery that surrounds events that happened in this area long ago.
James Gibson, LDEO
into the field where they undoubtedly got a little mud on their tires.
seismograph will be installed amid the sandy surroundings of a Ponderosa Pine farm.
Adrian Gutierrez, 13 March 14
7:30 am: Leave Georgia Southwestern State University, where we are staying, and head to the site8:20 am: Arrive at site 8:30 am: Start drilling and take geological samples every 5 ft.
11 March 2014
9 March 14
Spanish moss lined trees along our transect south of Valdosta
5 March 2014
We have drilled 2,600 feet below the sea floor and in another 500 feet, will reach the crystalline igneous basalt of the ocean crust. Though finding the age of the basalt is our main aim, the thick sediments that overly the crust also have a story to tell. As the sediments build up over time, they record the geological and climate history of the region.
There are the muds, silts, and sands, shaken loose from shallower depths and transported by gravity down-slope to the deep basin, where our first drill site is located. Ultimately, these sediments come from erosion of the surrounding land, and in this tectonically active part of the world, there is a lot of erosion going on. The island of Taiwan, for example, is being tectonically uplifted at a rate of about 0.2 inches per year, and is being eroded at about the same rate. This may not sound like much uplift, but imagine a world without erosion, Taiwan would stand 12 miles high after 4 million years. All that eroded rock ends up on the seabed, and some of it may find its way to our site.
There are the tiny shells of foraminifera and coccolithophores (familiar to us as chalk, in their pure rock form). They form a continual rain from the sea surface, and build up slowly but steadily on the seabed. The overturn of marker species shows us the age of the sediments, and their chemistry carries a record of ocean temperatures in the past.
Finally, there are volcanic sediments – from thin ash layers from distant volcanoes, to thick beds containing coarse chunks of rock exploded from nearby volcanoes. The close volcanoes are no longer active, and some have sunk beneath the sea to become seamounts. We will know from the depth of these beds in the sediment succession when the volcanoes erupted and for how long they were active.
This diversity means there is always something new and interesting to see in each 33-foot-long core that comes up from the sea bed, each another chapter in the geological history of the South China Sea. Among the 32 scientists on board, we have specialists in sedimentology, micropaleontology, volcanology and other fields. We are an international group; about half of us hail from China, a quarter from the U.S, and the rest from Australia, Brazil, France, Switzerland, Japan, Taiwan, and the Philippines (so there’s a good mix of music in the core laboratory – very nice). And that’s just the science party – the ship’s crew is almost as diverse.
Five days after leaving Hong Kong, the JOIDES Resolution is on site and drilling into the muds and silts of the South China Sea. The expedition’s main objectives are tectonic in nature, and I’m not really a tectonicist (I’m on board for the borehole logging), so for me this cruise is a crash course in the geological history of this area.
The origin of the ocean crust under the South China Sea is enigmatic, and there is ongoing scientific debate about which tectonic forces pulled apart the crust here to form the basin. In one hypothesis, the collision of India into Asia that built the Himalayas and pushed out Indochina to the southeast had the collateral effect of causing extension to form the South China Sea. The leading rival hypothesis says that the extension resulted from slab-pull from subduction at the southern edge of the basin (Borneo and Padawan). Of course, there are theories that mix the two, as well as minor-party candidates (plumes!).
The expedition aims to test the competing hypotheses by dating the earliest ocean crust (at the northern edge of the basin) and the youngest ocean crust (close to the now-inactive spreading center). If the age interval of sea floor spreading matches the age of the extrusion of Indochina (lets say 35 to 16 million years ago), then the Indochina extrusion hypothesis gains support; but if we find different ages, other hypotheses will move up the leader board. The debate and this expedition add to our understanding of the basic forces that shape the Earth’s surface.
Until now, the dating and interpretations rely on magnetic sea floor anomalies and other geophysical surveys. We will date the rocks directly for the first time, by argon-argon dating of the basalt that forms the ocean crust, and by the age of the sediments sitting on the basalt. The tricky part is that the basalt lies under 950 meters of sediments at the first site, and under 1850 meters at the second. To drill to this depth and bring back 100 meters of basalt is challenging to say the least, but there is a highly experienced drilling crew on board, so we are in with a shot. I’ll let you know how we get on!
This week, we are launching a test of “IceTracker”—a tool that allows users to see the trajectories of Arctic sea ice forward or backward from any day between 1981 and 2012, as well as other data including sea-ice speed, air temperature, water depth and the age of the sea ice along the track. We think IceTracker will be useful not only for Arctic research and policy, but for bringing the Arctic sea ice alive for students and the general public.
Researchers interested in climate and arctic dynamics will be able to assess the origin and melt location of sea ice, and seasonal and year-to-year variations in drift trajectories from specific locations. They will also be able to look into the transport of sediment or contaminants on or in the ice; this might for instance shed light on potential trajectories of oil spilled in ice-covered waters, or habitat changes that might affect the foraging patterns of polar bears or other creatures.
The IceTracker might eventually be used to consider future management options in the Arctic. Among these: projecting where declining sea ice is likely to persist, providing future potential refuge for threatened arctic creatures (an idea that got a lot of attention at AGU in 2010). It can even be used to recreate historical events; we used it to figure out where Fridtjof Nansen and his crew would have drifted had they frozen their ship into the ice today, rather than during their famous 1893-1896 trans-Arctic drift.
IceTracker is an excellent inquiry-driven research environment for any student with access to a computer. Teachers can use the IceTracker in guided exercises, or let students work on their own to learn about ice dynamics, interannual variability and climate change. For instance, we have set up team competitions where students can vie to be the first to reach the North Pole by drifting with the ice, or to make it out alive through Fram Strait. By exploring the Arctic in this way, the IceTracker lets students do their own sampling of a real-world non-linear system. They can see how diminished ice cover has changed ice speed, and demonstrate for themselves how initial conditions can affect ice movements much farther down the line.
Others might use IceTracker to consider historical conditions in planning adventure expeditions, or to visualize changing conditions for Arctic wildlife.
We will present IceTracker at AGU on Friday, Dec. 13, at the Moscone South poster hall (look for abstract number C15A-0490). You can also try running trajectories yourself at our beta testing web site: www.thepolarhub.org. We would appreciate ideas on how to make it better. Send feedback to: email@example.com.
The project has received funding from the U.S. Office of Naval Research and the U.S. National Science Foundation.
Some further resources:
Fowler, C. and M. Tschudi. 2003. Polar Pathfinder Daily 25 km EASE-Grid Sea Ice Motion
Vectors. Boulder, Colorado USA: NASA DAAC at the National Snow and Ice Data Center.
Pfirman, S., G.G.Campbell,B. Tremblay, R. Newton, W. Meier. New IceTracker Tool Depicts Forward and Backward Arctic Sea Ice Trajectories AGU San Francisco, December 2013. C51A-0490.
Pfirman, S., C. Fowler, B. Tremblay, R. Newton, 2009a. The Last Arctic Sea Ice Refuge. The Circle, 4:6-8. http://www.panda.org/what_we_do/where_we_work/arctic/publications/the_circle/?183741/The-Circle-0409
Pfirman, S., B. Tremblay, C. Fowler, 2009b. Going with the Floe: An analysis of the epic expeditions of Fridtjof Nansen and Sir Ernest Shackleton. American Scientist, 97: 484-493.
Stephanie Pfirman is Hirschorn professor of environmental science at Barnard College, and an adjunct senior scientist at Lamont-Doherty Earth Observatory.
Are you attending the American Geophysical Union (AGU) meeting this week in San Francisco? Are you interested in hearing from social scientists about Natural Hazards? The Center for Research on Environmental Decisions (CRED) will be there to answer your questions. Below is a schedule of sessions that CRED researchers are speaking at or convening.
We hope to see you there. If you can’t be at AGU in person we encourage you to livestream the sessions here.
Katherine Thompson, CRED PhD candidate, “The Problem with Probability: Why rare hazards feel even rarer”
Tuesday December 10, 1:55-2:10 PM PST, 2000 (Moscone West)
Session: Why Should We Talk About What We Don’t Know? Implications of Communicating Scientific Uncertainty II
How is probability of natural hazards events actually used by decision makers? The presentation will make recommendations on presenting probabilistic information to best take advantage of people’s tendencies to either amplify risk or ignore it, as well as recent findings that may shed light on ways that the negative effects of uncertainty can be mitigated.
David H. Krantz, CRED co-director, “Coordination of Individual and Organizational Planning for Natural Hazards”
Thursday December 12, 1:40-1:55 PM PST, 3002 (Moscone West)
Session: Climate Change Effects on Natural Hazards: Science, Communication and Policy I
Dave Krantz will explore the four different kinds of decision aids needed to improve natural hazard planning: mechanisms that support horizontal dissemination of plans, mechanisms that support vertical dissemination, mechanisms for examining goal conflicts and reducing these through plans that take others’ goals into account, and mechanisms for examining belief conflicts.
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
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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