Ice covers about 98% of Antarctica. An imaging technique allows us to see what the continent would look like without ice. Explanations.
This imaging technique is the Bedmap2. It was created in 2013 using significant amounts of data on surface elevation, ice thickness and bedrock topography collected by the British Antarctic Survey and NASA from aircraft, surface surveys and satellites.
Without ice, Antarctica becomes a rugged land covered in mountain ranges, rugged terrain and gorges. Scientists also found part of the bed under the Byrd Glacier in Victoria Land. It sits 2,870 meters below sea level, making it the lowest point on Earth’s continental plates. “The bed map shows, in unprecedented detail, the bedrock beneath the Antarctic ice sheets. Before, we had a regional overview of the topography, but this new map, with its much higher resolution, shows the landscape itself; a complex landscape of mountains, hills and rolling plains, dissected by valleys, hollows and deep gorges”said Peter Fretwell of the British Antarctic Survey in a 2013 statement.
One of the tools used to collect this data was an ice-penetrating radar instrument. It is a radar depth sounder. It can determine in particular the thickness of the ice and the subglacial topography.
Scientists explain that it is important to understand what shape the world looks like under the ice of Antarctica. This world does have an impact on the distribution of ice and its melting in the face of rising oceans and temperatures due to climate change. “Ice caps push up because of snow and, like honey poured on a plate, spread outward and thin due to their own weight”explained Sophie Nowicki, an ice sheet scientist at NASA’s Goddard Space Flight Center in Greenbelt, in a different statement. “The shape of the bed is the biggest unknown and affects how the ice can flow. You can influence how the honey spreads on your plate, simply by varying the way you hold your plate. »
The data collected by Bedmap2 ultimately reveals that Antarctica is home to 27 million cubic kilometers of frozen water. If it were to melt, the sea level would rise about 58 meters. In order to better understand the thickness of the ice and the world below Antarctica, scientists are now building a next-generation map: Bedmap3.