geophysics

McCarthy snip

Christine McCarthy: A Cheerleader for the Physics of Ice

Christine McCarthy, a geophysicist at the Lamont-Doherty Earth Observatory, scrunches blocks of ice between hunks of rock to study how ice behaves under pressure. Her work provides an important piece of the puzzle of how glaciers move, what makes them speed up, and how they are contributing to sea level rise as the climate warms.

by |June 26, 2017
D'Entrecasteaux Islands

The Downs and Ups of Mountain Building

In the islands off Papua New Guinea, the rocks are giving rise to new ideas about the ways mountain chains form. A new scientific model shows how two seemingly opposite processes can take place in the same region.

by |August 18, 2015
Antarctica, NBP1503 science team

Smooth Sailing Back to Tasmania

After a surprisingly smooth crossing of the Southern Ocean, with favorable winds we arrived back in Hobart, Tasmania. The weather maps show that we just got ahead of another big storm system.

by |May 1, 2015
NB Palmer, West Antarctica, CTD system

Taking a 4,000-Meter-Deep Profile of Antarctic Waters

In addition to understanding potential pathways for “warmer” circumpolar deep water to reach the ice shelf, we are also measuring what the structure and properties of the water column are and determining if there is already warmer water on or near the continental shelf that could already interact with the glaciers of East Antarctica today.

by |April 27, 2015
In addition to depth, we can identify many features in the high-resolution multibeam data that we produce. Most of the seafloor near the shelf break (where the water is between 300 and 500 meters deep) is covered with these irregular furrows that are created when large icebergs are grounded here.

Mapping the Seafloor

One of the goals of this expedition is to investigate if water from the Southern Ocean with temperatures above the melting point of glaciers could reach the glaciers in East Antarctica, and if there are any obstacles on the seafloor of the shelf that impact the ability of such water to reach the glaciers and ice streams.

by |April 20, 2015
Some examples of the sea ice that we have encountered so far. Top left: bands of grease ice, Top right: small pancake ice merged together; bottom left: larger pancake ice; bottom right: The Nathaniel B. Palmer steaming through dense sea ice cover.

In the Ice

Several days ago we reached our main work areas along the margin of East Antarctica. Our expedition is relatively late in the season and the seas around Antarctica are starting to freeze.

by |April 10, 2015
During our transit south to Antarctica we deployed seven ARGO floats (yellow device in picture) for the University of Washington. They drift with the currents in the oceans, measure profiles of salinity and temperature and send those via satellite to researchers on land. They are part of an international effort to better monitor the conditions of the oceans.

Closing in on Antarctica

We are less than a day away from our first study area on the continental shelf in front of the Dibble Glacier. As we approach Antarctica we are starting our science program with a 4500 meter deep CTD and multibeam acquisition.

by |April 6, 2015
Map showing the planned track of our expedition with the modifications made due to the storm systems. Our main study areas are on the continental shelf in front of some major East Antarctic glaciers.

On Our Way: Avoiding the Storm

We are now aboard the R/V Palmer and on our way to East Antarctica. Due to¬†two storms in our direct way we are heading west first to go around the storms and we’ll then head south on their backside.

by |March 30, 2015
The icebreaker Nathaniel B. Palmer, our home for the next seven weeks, docked at the pier in Hobart, Tasmania.

Preparing for Seven Weeks at Sea

For our spring expedition, NBP1503, to the margin of East Antarctica we will live and work on board the United States icebreaker Nathaniel B. Palmer. Together we are eight scientists, 10 science support staff and 19 crew members of the ship’s crew.

by |March 23, 2015