Science Spotlight

Station PALM


Researcher: Grace Nield
Newcastle University
United Kingdom


GPS antenna on a pole at site PALM in Antarctica. The photograph is from the Antarctic summer so most of the coastal snow and ice is melted. An iceberg can be spotted in the background though.


Name: Palmer
State: Antarctica
Country: Antarctica
Elevation: 31.2 m
Lat/Long:  -64.7751 / 295.949

Rapid Bedrock Uplift Due to Glacier Melt in Antarctica

When ice melts from a glacier it doesn't just raise sea levels, it changes the shape of Earth. In particular the Earth rebounds. That rebound provides a natural experiment that allows us to study the interior of Earth - parts of the Earth we cannot access directly because they are tens or hundreds of miles underground. The rebound is governed by (1) Earth's internal makeup and (2) how much ice has been melted.

Turning the problem around, if we measure the rebound with GPS and determine the amount of ice melted with satellite measurements, we can study the interior of Earth. In this project we are measuring how a GPS site in Antarctica is rebounding following the collapse of a series of large ice shelves since the late 1980s. In particular we're using data from the GPS site at the US Palmer Station (see Figure 1) located on the Antarctic Peninsula and recording nearly continuous data since 1998. Colleagues have mapped the glacier elevation change and we are using the GPS with these maps to understand the Earth interior.

Check out these videos:

Figure 1. Palmer Station from the air (top) and sea (below)


Figure 3. The weight of glacier ice causes the crust to subside. When the glacier starts to melt the crust begins to rebound.

 

Figure 2. Elevation change of glaciers flowing into the Larsen B Ice Shelf from 2002 and 2006.


Figure 4. Position changes for PALM in the ITRF2008 reference frame.

Spotlight Questions

  1. How far has the site moved horizontally since it has been operating? How does that compare with other places in the world?
  2. Look at the height - how fast was it going up or down in the first few years? How fast is it going up more recently?
  3. How does the change compare to the time when the Larsen B Ice Shelf broke up?

Last modified: 2019-12-26  16:24:51  America/Denver  

 

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