Mapping Antarctica’s Bedrock with Bedmap2

Antarctica has long been a fascination for scientists and researchers, and a new map is causing excitement for experts who want to understand more about the southern continent. The map, called Bedmap2, provides a detailed look at Antarctica from its surface of ice all the way down to the bedrock. The map was compiled by the British Antarctic Survey using data from other research organizations around the globe including NASA. Scientists are hopeful that the new map will help them understand how changes in the ice affects the rest of the globe and lead to enhanced simulated models of ice flows in response to climate change.

To build the map, researchers had to shift through a large amount of data from a variety of sources and compile decade’s worth of measurements on Antarctica. One of the biggest contributors to the map has been NASA which has been gathering information over the last several years related to ice thickness, surface elevation, and the parameters of the ice shelf. NASA has been doing this through the ICESat (Ice, Cloud, and Land Elevation Satellite) and Operation IceBridge. In particular, ICESat was instrumental in helping researchers build the map grid for surface elevation in areas that were hard to measure like mountainous terrain using radar and laser altimetry. ICESat was also used to verify the accuracy of other data sets.

NASA’s Operation IceBridge has also been critical to the development of Bedmap2. Operation IceBridge is a six-year airborne survey of Antarctica, and it has been collecting information on areas of the continent not previously surveyed. One of those areas is called the Recovery Ice Stream and IceBridge put it on the map in 2011. IceBridge uses ice-penetrating radar to send signals through the ice. It then records the angle and timing of returning waves to gather measurements on ice thickness and the topography underneath the ice. Moreover, NASA contributed to the map by making the data from ICESat and IceBridge freely available to researchers, something they hope to continue doing.

Bedmap2 provides greater detail and accuracy over the earlier version of the map called Bedmap. The original Bedmap was produced over ten years ago and did not have the same amount of detail that Bedmap2 contains. Both of the maps are laid out in a grid pattern over the continent, but Bedmap2 incorporates tighter grid spacing. This allows for more detail and includes features that were too small in the earlier version. The result of over 25 million additional measurements from satellites, surface readings, and airborne missions is that Bedmap2 has improved accuracy, greater resolution, and more coverage than before. Researchers also made extensive use of GPS technology to gather data on the bedrock, ice thickness, and surface elevation.

Scientists are hopeful that the end result will be more accurate calculations of ice volume and better ways to predict how the ice moves and changes. The Antarctic ice sheet not only contains half of the world’s fresh water but it is also constantly changing as the ice flows towards the sea. By mapping the underlying bedrock and measuring the thickness of the ice, scientists can more accurately predict sea level rise and improve our understanding of how the ice of Antarctica transforms in response to changes in the Earth’s climate. Up until now, this has been a challenge because of limited data on what lies underneath the ice sheet.

Bedmap2 also has the potential to allow researchers to create better models of how the ice sheet will move and respond to changes in air and ocean temperatures. A major ice sheet covers Antarctica, and researches use computer simulated models to try and predict how this ice sheet will respond to climate change. To be able to create accurate models, researchers need to know the shape and structure of the underlying bedrock since features in the bedrock determine how the ice actually moves. Bedmap2 could help researchers create more realistic models in the future. Although Antarctica is one of the least understood areas of the globe, scientists are hoping this will change because of the Bedmap2.

Reference

“NASA’s IceBridge Mission Contributes to New Map of Antarctica.” NASA.gov. NASA, 4 June 2013. Web. 18 June 2013.