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Deep Ocean Heat Is Melting Antarctic Ice

AGU 2010 - Tue, 12/14/2010 - 13:23

Like dirt swept under the carpet, some of the human-made heat produced over the last century has been getting soaked up by the world’s oceans, and sinking into deep waters. Now, it is coming back to haunt the surface, in a very sensitive place: western Antarctica, where vast ice sheets meet the ocean. The result appears to be that ice is rapidly being eaten from the bottom, says Douglas Martinson, a polar scientist at Lamont-Doherty Earth Observatory, who presented the findings Monday at the fall meeting of the American Geophysical Union.

Warm waters carried by the Antarctic Circumpolar Current are brushing the ice front in the western part of the continent, in the area of the Bellingshausen Sea.

Warm waters carried by the Antarctic Circumpolar Current are brushing the ice front in the western part of the continent, in the area of the Bellingshausen Sea. (Click to enlarge. Courtesy Douglas Martinson, Lamont-Doherty Earth Observatory)

Martinson said that heat stored in deep waters far from Antarctica is being pushed southward and becoming entrained in the Antarctic Circumpolar Current, a vast, wind-driven water mass that constantly circles the frozen continent. The evidence comes from 18 years of Antarctic voyages Martinson has made to measure water temperature, salinity and other qualities at different depths. He called the increases in ocean heat in the past few decades “jaw dropping.” Temperatures have risen only a few degrees above the melting point–but that is all it takes to cut at the ice front. “This is like a huge freight of hot coals–fresh, hot water being delivered right to the the front door,” he said.

This raises the specter of sea-level rise driven by melting in this region–but there is a larger implication, said Martinson. Even if all sources of human-produced carbon dioxide in the air were cut off, the built-up heat will remain in the ocean for many years to come. “Pretend your brains out that the politicians did something to stop global warming tomorrow.  Even if they did, we will still have decades and decades of upwelling of that warmed water eating ice,” he said.

Read a Discovery News article about Martinson’s talk.

18,000 Scientists–In One Place

AGU 2010 - Mon, 12/13/2010 - 01:13

This week marks the world’s largest annual gathering of earth and space scientists: the five-day December meeting of the American Geophysical Union. There will be about 18,000 of them, spread across two giant San Francisco convention halls giving talks and discussing the latest in their fields. Scores of researchers from the Earth Institute will be involved. Among many other things, they will give presentations on the destruction of Antarctic ice by warming oceans (from Douglas Martinson, Lamont-Doherty Earth Observatory);  clues contained in ancient trees as to how climate change may affect New York City (Neil Pederson of Lamont); an examination of India’s water crisis (Shama Perveen of the Columbia Water Center); and fast-growing “hotspots” of potential weather-related disasters in the Caribbean” (Bob Chen, director of the Center for International Earth Science Information Network).

On brighter notes, William Ryan and colleagues at Lamont will demo a new mobile app called Earth Observer, scheduled to be released this week at the Apple iTunes store, which gives the general public access to fabulous graphics and information about the earth previously tapped mainly by scientists.  There is also the traditional Lamont-Doherty alumni party, held every year on Tuesday night at AGU—a gathering that reunites top scientists from across the world who studied at Lamont.

Check out our press advisory for journalists , detailing just a few of the significant and interesting talks from Earth Institute staff: http://www.earth.columbia.edu/articles/view/2637.

Return to Malawi: Bringing Home Instruments and Earthquake Data

Retrieving seismic equipment

Retrieving seismic equipment

In early May, Scott Nooner and I returned to Malawi to retrieve our seismic equipment and finally lay eyes on the data recorded over the last 4 months. Picking them up was vastly easier than putting them out. In contrast to the days studying out-dated maps and driving down dirt roads looking for sites, and hours of hard labor under the hot African sun digging holes and constructing vaults, recovery required only minutes at each site to shut down the equipment and safely stow it in plastic cases in the back of our rented truck. It took us about a day to recover all the equipment that we spent a week installing. Since we recovered the seismic equipment so quickly, we had time to collect new GPS data, too.

Although retrieving the seismic equipment proved easy, transporting numerous 50-lb boxes from one side of the world to the other is not trivial, as we discovered during the deployment. Our hasty departure in January prevented us from obtaining US customs documentation that would have simplified the export/import process, and our seismic equipment had to return from Malawi the way it came in – as checked luggage. We wrested ten ~50-lb pieces of baggage to the check-in counter at the Lilongwe airport, and handed over all of our remaining dollars plus a fistful of Malawi Kwacha for excess baggage fees. Checking in for each subsequent leg of the trip, we braced ourselves to part with more money. Even for the few pieces of equipment that we transported back to the US via a commercial shipper, we faced interesting challenges. The Karonga DHL office lacks a scale, so shipping agents and our Geological Survey colleagues made competing guesses as to the weight of our boxes and compromised on the average when charging us shipping fees.

Example of aftershock recorded on four seismic station on Jan 19, 2010

Example of aftershock recorded on four seismic stations on Jan 19, 2010

Far and away the best part of recovering instruments is the chance to take a first look at the data, and our new dataset from Malawi did not disappoint. While sipping complementary wine on the long flight from Johannesburg to Atlanta, I perused the recordings from our seismometers. While (thankfully) there were no recurrences of the damaging events from December, to my delight I saw that we have recorded a remarkably persistent series of aftershocks. For our purposes, the more aftershocks, the merrier! We plan to determine the location of each aftershock to map out the structures below Earth’s surface that caused the large sequence of earthquakes in December. Stay tuned…..

How Volcanoes Can Change the World - CNN

TRL Featured News - Fri, 04/16/2010 - 10:24
Lamont scientist Rosanne D'Arrigo discusses the global impact on climate from Iceland's Laki volcano eruption in 1783-84.
Categories: TRL

What happened at Angkor Wat? - The Washington Post

TRL Featured News - Sat, 04/03/2010 - 12:00
Discusses study led by Lamont scientist Brendan Buckley.
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Drought and flooding led to collapse of Angkor - Los Angeles Times

TRL Featured News - Wed, 03/31/2010 - 12:00
Discusses new study led by LDEO scientist Brendan Buckley.
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Reaching Out: Educating Specialists and the Public on Earthquake Monitoring

Curious Malawian policemen watch Donna, Winstone and Patrick download seismic data.

Curious Malawian policemen watch Donna, Winstone and Patrick download seismic data.

While installing our seismic network in Malawi, we interacted with everyone from scientists to schoolteachers, and journalists to villagers. The opportunity to provide information and education to Malawians has been the most rewarding aspect of our effort. We trained local scientists and technicians on seismic equipment and data analysis, and educated the public on earthquakes and earthquake monitoring both in person and via media interviews. The Malawi Geological Survey Department (MGSD) prompted our visit by requesting assistance in monitoring aftershocks, and we hope that this temporary seismic deployment will empower them to obtain resources and training for a permanent seismic network.

Because we deployed our seismic stations near schools, clinics and other centers of village life, we met a wide spectrum of Malawians. Everyone we spoke with expressed interest in our undertaking and wanted to know more about the chindindindis (earthquakes in Tumbuka). In the village of Mpata, 5 miles west of Karonga, a crowd gathered around a laptop balanced on the hood of our 4×4 as Jim showed them aftershocks in newly downloaded data; the audience peppered him with pertinent questions about the East African Rift and earthquakes beneath Lake Malawi. Curious policeman looked on as I retrieved seismic records from a station positioned near a checkpoint ~10 miles north of Karonga, inquiring when and where the next earthquake would occur. Science teachers in Mlare helped us install a station near their school and received an impromptu lesson in plate tectonics and seismology.

Journalists from newspapers, radio stations and national TV programs also interviewed us during our visit, which allowed us to communicate with a larger audience about possible causes of the earthquakes and the benefits of monitoring them.

Jim gives a lesson in data analysis to Loveness, Winstone, and Patrick.

Jim gives a lesson in data analysis to Loveness, Winstone, and Patrick.

We worked side by side with scientists and technicians from the MGSD every day of our visit. They taught us local geology, local customs, and local language, and made our joint endeavor possible by facilitating contacts with national and regional officials. In return, we brought them seismic monitoring equipment, helped them deploy it, and taught them new techniques for analyzing the resulting data. Although the MGSD is charged with monitoring earthquakes within the Malawi rift valley, their efforts are severely hampered by paucity of data and lack of training. Only two seismic stations exist in Malawi (provided by Africa Array), and university-level courses in seismology are almost non-existent. The data and training of MGSD employees provided by our temporary deployment following the Karonga earthquakes will help mitigate these problems in the short term; we hope that this experience will equip the MGSD with the ammunition to argue for more national and international resources for seismic monitoring in Malawi over the longer term.

Hydrothermal Vents Sometimes Colonized From Afar - Science News

TRL Featured News - Fri, 02/26/2010 - 16:46
At that rate, a larva could be wafted about 300 kilometers in a month, said Andreas Thurnherr, a physical oceanographer at the Lamont-Doherty Earth Observatory in Palisades, N.Y. He and a colleague reported analyses of currents along the East Pacific Rise at the meeting on the same day as Mullineaux’s presentation.
Categories: TRL

Risks and Rewards: funding a technical earthquake response

Donna Shillington explains seismic network to Malawi TV

Donna Shillington explains seismic network to Malawi TV

A rapid technical response to the damaging earthquakes in Malawi produces both humanitarian and scientific benefits, and we hoped that both scientific and international assistance agencies would support our effort. Our seismic field effort serves two purposes: (1) to provide badly needed seismic equipment and technical training to the Malawi Geological Survey department (MGSD); and (2) to obtain unique data from very close to the earthquake sources to develop a better scientific understanding of faulting in the East African Rift. Funding has proven difficult, however, and our experience suggests that a technical component to earthquake response often falls through the cracks of the broader relief effort.

The Malawi earthquake sequence spawned a modest international response by several organizations with complementary and overlapping goals. The US Agency for International Development (USAID), through the Office of Foreign Disaster Relief (OFDA), and international organizations (e.g., Red Cross) provided direct humanitarian response: food, water, shelter, and other necessities for the displaced people of Karonga. Two scientists from the US Geological Survey (USGS), with support from USAID, provided a post-earthquake assessment based on field observations of damage and faulting, which constituted the official US government technical response.

 Charles Kankuzi and Loveness (MGSD), Donna Shillington and James Gaherty (LDEO), Walter Mooney (USGS), Winstone Kapanje (MGSD), Frederick Simon (USGS), Nathan and Patrick Chindandali (MGSD).

Earthquake responders in Karonga. Left to right: Charles Kankuzi and Loveness (MGSD), Donna Shillington and James Gaherty (LDEO), Walter Mooney (USGS), Winstone Kapanje (MGSD), Frederick Simon (USGS), Nathan and Patrick Chindandali (MGSD).

Our technical response parallels those efforts, and is typical for the US academic community; individual scientists with existing contacts in and working knowledge of the effected region provide seismological field equipment, analysis, and training. Responding to the earthquakes in a timely manner required an almost instantaneous commitment on our part. Within two days after the largest event, IRIS had mobilized instruments and the funding necessary to ship them to the field. Lamont-Doherty Earth Observatory (LDEO) and the Earth Institute (EI), both at Columbia University, promised to “backstop” our effort – in other words, cover our travel and field expenses while we sought external funding for our effort. Both have strong and long-standing commitments to mitigating earthquakes, hazards, and human suffering worldwide, including in East Africa and Malawi. The project would have immediately stalled without this support.

With the LDEO and EI backstop in hand, we sought external funds from the National Science Foundation (NSF) and USAID, highlighting the unique scientific and outreach opportunities offered by a rapid response to these earthquakes (read our proposal here). USAID characterized the activity as too scientific to be in their purview and declined to fund us. NSF acknowledged a modest scientific benefit, but they described the effort as primarily a humanitarian and outreach response. While NSF agreed to provide some support, the amount available for such short-turnaround projects (via the RAPID program) is very small – enough only to return and recover our instruments.

Technical responses such as this one provide scientific and humanitarian benefits alike and strongly complement the larger response effort. The breadth of the impact should increase their fundability – more bang for the buck. But because of the splintered nature of the US response and funding mechanisms, this breadth can be a detriment to obtaining funding – too scientific to be humanitarian, but too humanitarian to be scientific. In our case, we overcame this quandary only with the strong financial support of our home institution. How many technical response efforts never get off the ground because of this funding uncertainty?

High, Dry and Safe: In Search of the Perfect Site

Stuck SUV a Local Attraction for School Children

Stuck SUV a Local Attraction for School Children

The ideal spot for a seismic station is dry, quiet and safe from vandals and thieves. Seismometers record slight ground motions, allowing them to hear distant (and not so distant) earthquakes. But cars or even kids playing near a seismic station can produce ground vibrations that overwhelm the subtle sounds of earthquakes. Seismic stations include plenty of expensive, high-tech instruments that are worthless to the average person. But they also contain mundane items that can be useful, such as 12-volt batteries and insulated wiring, making theft a problem. And water is the enemy.

Malawi presented novel challenges for siting our stations. Our first priority was to find dry, secure locations to prevent damage and loss. As we drove into the Karonga region for the first time, our hearts sank; the epicentral region is low-lying and wet, small villages surrounded by rice paddies. Our arrival during the rainy season did not help.

But with a little hunting, we were able to find high and dry spots for most of our stations. We bumped along narrow village tracks in our rented 4×4, occasionally getting stuck on particularly muddy sections. Most of the dirt roads did not appear on our outdated maps, so we stopped regularly to ask for directions. When our Malawi colleagues explained that we were there to learn about the chindindindis (Tumbuka for earthquakes), they were eager to help!

Jim, Loveness and Hassan wait under mango tree for go-ahead to install station

Jim, Loveness and Hassan wait under mango tree for go-ahead to install station

In many parts of the world, safety and quiet can be achieved simultaneously simply by deploying stations in the middle of nowhere. This is not an option in densely populated Malawi, where one farming village abuts another. Main thoroughfares and small dirt roads alike were crowded with kids walking to school, villagers biking to town, and farmers grazing their goats and sheep. Instead, we sought out village police, teachers, and other officials for help finding safe spots. In some cases we hired guards to look after them.

We spent hours driving, inspecting sites and waiting to meet with officials. We normally skipped lunch, fueling ourselves instead on passion fruit-flavored Fantas and “puffs” (kids junk food akin to cheese doodles). But these efforts paid off – we found good sites for our equipment and started listening.

A Rough Start

Seismic stations awaiting transport.

Seismic stations awaiting transport.

The magnitude 6.0 earthquake that struck Malawi on Saturday night, December 19, spurred us into action. We had been closely following the earthquakes there, but this one confirmed the unusual nature of the seismic sequence. It also happened to be the most destructive. Leonard Kalindekafe, director of Malawi’s Geological Survey, asked us to come and monitor the ongoing quakes. However, mobilizing the needed equipment over the holidays turned out to be a challenge.

Within two days, we located ten seismometers: eight from the Incorporated Research Institutions for Seismology (IRIS), and two from Cindy Ebinger, a seismologist at University of Rochester in upstate New York. Cindy offered to send us her instruments, which we would carry on the plane with us. IRIS planned to ship their instruments directly to Malawi. On Christmas Eve, as we headed home to our families, everything seemed to be in order. We purchased plane tickets for Dec. 30, and planned to celebrate New Year´s Eve in Lilongwe, Malawi’s capital, with a couple of Carlsberg Specials at the Diplomat Pub. From there, we would head north to the epicenter.

Not all of it happened as planned. Shipments were canceled. Boxes went missing. Flights were changed. Shipping the IRIS equipment directly to Malawi required two weeks in transit, minimum. We considered wild back-up plans: “Let’s truck everything from Johannesburg to Malawi!” Just as quickly we rejected them: Johannesburg is 1,000 miles away, and would have required four border crossings.

More or less everything that could go wrong, did. The delays and false-starts were particularly frustrating since the clock was ticking; the rate of aftershocks declines steadily following a major earthquake. Each day of delay meant less information about the origin of the big earthquakes.

After two days of arranging and rearranging, hair pulling and hand wringing, we departed New York on New Year’s Day with equipment for five seismic stations, all of it packed into our checked luggage. We even crammed two seismometers into our carry-on backpacks; they passed through security at JFK apparently unnoticed. Eighteen hours later our eight 50-lb bags arrived at the VIP customs lounge in Lilongwe. Leonard helped speed us and our equipment through customs. Within an hour, we were in a 4×4 speeding towards Karonga. Almost nothing went right prior to our departure from JFK; from that point forward, nothing really went wrong.

East Coast Basalt and Carbon Sequestration - NPR Talk of the Nation

TRL Featured News - Fri, 01/08/2010 - 10:32
Basalt formations off the East Coast of the U.S. could suck up a billion tons of carbon dioxide, according to a new study. Paleontologist Paul Olsen, of Columbia University's Lamont-Doherty Earth Observatory, explains how to get the CO2 into the rocks, and why scientists believe it won't leak out.
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Climategate, global warming, and the tree rings divergence problem - The Christian Science Monitor

TRL Featured News - Mon, 12/14/2009 - 16:19
Much discussion of the Climategate e-mails has centered on tricking tree ring data that may not confirm global warming. Quotes LDEO scientist Roseanne D’Arrigo and discusses her tree ring work in Alaska.
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