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Lamont-Doherty scientist Andy Juhl has found that debris washed up after Hurricane Sandy showed signs of sewage contamination.

A new study by a team of researchers at Lamont-Doherty predicts a 10 percent drop in the Colorado River's flow in the next few decades which could disrupt longtime water-sharing agreements between farms and cities in the U.S. Southwest.

New York City is poised to finish its warmest year since modern record-keeping began, with an average temperature projected to top 57.2 degrees. As a symbol, Sandy was significant, said Lamont-Doherty scientist Adam Sobel. "But if next year doesn't break the record again, it won't mean global warming has slowed," he said.

Francesco Fiondella is normally behind the scenes writing web stories, developing audio slideshows and videos for the International Research Institute for Climate and Society (IRI). But at this year’s annual American Geophysical Union (AGU), the tables were turned for a brief moment. He was video ambushed by climate scientist Andrew Robertson and forced to explain [...]

 

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Currently email service is down for most users due to multiple hardware failures.  We are working on the problem.  There is no estimate as to when we will be back up.

 Mail service for many users is down due to mutiple hardware failures.  We are working on the problem.

Focusing on the American Midwest, Andrew Robertson analyzes the relationships between floods, weather and climate patters throughout the 20th century.

In the spectacular collapse of ice sheets as the last ice age ended about 18,000 years ago scientists hope to find clues for what regions may grow drier from human caused global warming. In a talk Thursday at the American Geophysical Union’s annual meeting, Aaron Putnam, a postdoctoral scholar at Lamont-Doherty Earth Observatory, painted a picture of earth’s dramatic transformation as seen in climate records extracted from ancient cave formations, ice cores, lake shorelines and glacial moraines.

Glaciers advance in colder temperatures, but sometimes a big rock avalanche can also make a glacier grow, new research results presented at the American Geophysical Union’s annual meeting suggests.

Nicole Davi, a postdoctoral scientist at the International Research Institute for Climate and Society and the Lamont Doherty Earth Observatory, thinks tree rings are an ideal way to motivate students to collect and analyze data as well as to learn about climate change.

Andrew Robertson, a climate scientist at the International Research Institute for Climate and Society, discusses his research on helping reservoir managers in northern India make better planning decisions by improving their ability to predict how climate change will influence water availability.

Researchers from the Earth Institute's Center for Research on Environmental Decisions will present their work at the 2012 American Geophysical Union Conference in San Francisco this week. Psychology doctoral candidate Katherine Thompson will present a poster entitled “The Psychology of Hazard Risk Perception”; and visiting research scholar Diana Reckien will present a poster entitled “Realities of Weather Extremes on Daily Life in Urban India—How Quantified Impacts Infer Sensible Adaptation Options.”

In this Q&A, Arthur M. Greene discusses improving climate and agricultural modeling in South America using a new stochastic simulation of future climate.

Public health professionals are increasingly concerned about the impact climate variability and change can have on infectious diseases such as malaria, dengue fever and bacterial meningitis. However, in order to study the relationships between climate and ...

Keep an eye on State of the Planet over the next week for updates on the fall meeting of the American Geophysical Union.

Scientists from Columbia University’s Earth Institute will present important new studies at the Dec. 3-7 meeting of the American Geophysical Union, the world’s largest gathering of earth and space scientists. Below: a chronological guide. Most researchers are at our Lamont-Doherty Earth Observatory (LDEO).More info: http://fallmeeting.agu.org/2012/ Reporters may contact scientists directly at any time, or call [...]

Mount Murphy rises through the ice sheet along the flank of West Antarctica, diverting the flow of ice around it (photo credit J. Yungel, NASA IceBridge Project)

1500 feet above the ground surface is where our suite of instruments normally operates, but for this flight we are taking them up higher, much higher, in fact over 20 times our normal range to 33,000 feet. Our flight plan is to repeat lines surveyed in a previous years by NASA’s Land, Vegetation Ice Sensor (LVIS) a scanning laser altimeter. LVIS has collected data as part of the IceBridge instrument suite in the past, but it was flown separately at high altitude on its own plane, in order to map large areas of both land and sea ice. This flight will refly some of LVIS’s work but using a subset of the instruments on our plane, narrow swath-scanning lidar, the digital mapping camera system, the gravimeter, and our depth radar.

At our higher elevation we will fly faster and can cover a lot of ground. The landscape of Antarctica can be hard to get ones head around – a glacier catchment is usually too big to fit into one field of view, so we see it bit by bit, and try to build up a physical picture in the same way we build up our understanding of the system – piece by piece. We have flown several missions into the Amundsen Sea region on the west Antarctic coast in the past, but this was the first time where we could really see the context of all of these different glaciers – flowing into the same embayment, forming ice shelves, calving ice bergs, and drifting northwards through the sea ice.

The flight offers views of some of the most noteworthy features in Antarctica. Pine Island Glacier, one of world’s fastest streaming glaciers, developed an 18 mile crack along its face in the fall of 2011 which spread further over the last few months. The crack will inevitably lead to breakage, dropping an iceberg which scientists have estimated will be close to 300 pound in size.

Crack along the front of the Pine Island Glacier as seen form the IceBridge forward facing camera.

The crack in the Pine Island Glacier as it is propagating further through the ice (Photo credit NASA IceBridge)

Bordering the glacier is one of two shield volcanoes we passed over during our flight. Pushing up through the Antarctic white mask, Mount Murphy diverts the ice streaming along the glacier. A steeply sloped massive 8 million year old peak, Mount Murphy pulls my thoughts back New York as it was named for an Antarctic bird expert from the American Museum of Natural History.

Mount Murphy, one of two shield volcanoes we overflew on this mission. (Photo K. Tinto)

From Mount Murphy we continue to the second shield volcano, Mount Takahe. Ash from 7900 years ago found in an ice core from the neighboring Siple Dome has been attributed to an eruption from this volcano. This massive potentially active volcano is about 780 cubic kms in size. The volcano was named by a science team participating in the International Geophysical Year (1957-8) after the nickname of the plane providing their air support …an unusual name for a plane as its origin is that of a plump indigenous Māori bird from New Zealand which happens to be flightless! Regardless the rather round Mount Takahe soars high above the glacier as we move overtop.

Mt. Takahe a slumbering volcano that is believed to have deposited evidence of an eruption in the ice almost 8000 years ago (Photo K. Tinto)

From there we fly over the tongue of Thwaites Glacier as it calves icebergs into the Amundsen Sea. To read more about Thwaites check out my first blog of the season: http://blogs.ei.columbia.edu/2012/10/18/launching-the-season-with-a-key-mission-icebridge-antarctica-2012/

The calving front of Thwaites Glacier. The neighboring glaciers of Pine Island and Thwaites are moving ice off West Antarctica into the surrounding ocean at a rapid rate (Photo K. Tinto)

For more on the IceBridge project visit:

http://www.nasa.gov/mission_pages/icebridge/index.html

http://www.ldeo.columbia.edu/res/pi/icebridge/:

Travel to the Ronne Ice Shelf involved passing by the Ellesworth Mountains. The range contains Antarctica’s highest peak, Vinson Massif at 4897 meters of elevation.

Named after Edith Ronne, the first American woman to set foot on this southern continent, the Ronne Ice Shelf is tucked just to the East of the Antarctic Peninsula on the backside of the Transantarctic Mountains. With an area measured at 422,000 square kms, this is the second largest ice shelf in Antarctica. This vast icy expanse stretches into an indentation in the Antarctic coastline called the Weddell Sea, and gained some attention this past spring when scientists identified a mechanism that will force warming ocean water up against Ronne, which over time will cause it to thin and weaken (Hellmer, H. H. et al., 2012). Ice shelves are important barriers slowing the flux of ice moving off the land into the surrounding ocean. Any weakening in the tight connection of this ice to the land, either at the bottom where the shelf freezes to the ground below or where at the edges where it is tightly fused to the continent, can have major impacts on the speed and volume (flux) of ice moving off the land and into the oceans.

Annotated Antarctic map showing the area of study.

The current mission is being flown to measure the flux of ice currently coming into the Ronne Ice Shelf from the surrounding Antarctic landmass. To determine this we focus on the ‘grounding line’, the area where the ice changes from being frozen solid to the land below to floating as part of the ice shelf. To understand how much ice is moving over the grounding line, we have to understand how much ice is at the grounding line, and to do this we have to fly along the grounding line (or slightly inshore of it).

The majestic Ellsworth Mountains, formed about 190 million years ago, are the highest range in Antarctica, and steeper than the Tetons. Their original name, Sentinel Range, describes their posture, as they watch over the Weddell Sea and the Ronne Ice Shelf.

In many areas of Antarctica, even knowing where the grounding line is takes a lot of work. Much of that work is done using satellite data through a process called “interferometry”. This process compares the returning radar signal from different satellite passes to determine where the ice begins to move under the influence of the ocean tides. In this scale, ice that is responding to the rise and fall of the tides is floating ice, and from this we can mark the grounding line. While technique identifies the grounding line, it does not show how much ice is moving across it; to determine that we need to collect ice thickness measurements. For today’s flight we moved just inland of the grounding line for about half of the Ronne Ice Shelf collecting ice thickness and other supporting data that will begin to fill in this important information.

Reference: Hellmer, H. H. et al. Nature, 2012. DOI:10.1038/nature11064. 


For more on the IceBridge project visit:

http://www.nasa.gov/mission_pages/icebridge/index.html

http://www.ldeo.columbia.edu/res/pi/icebridge/

 

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