A new robotic study conducted by a coalition of scientist from the United Kingdom, Australia and United States has shown that the Antarctic sea ice is thicker than previously thought.
The SeaBED autonomous underwater vehicle (AUV) has allowed for more in-depth sea ice analysis than scientists have previously been able to garner from drill data measurements, ship visual measurements (that are unable to access thicker areas) and satellite images (snow cover hinders analysis of images) alone. SeaBED is able to access areas that have previously been inaccessible to researchers.
The SeaBED AUV from Woods Hole Oceanographic Institution (WHOI) is fitted with a camera that enables it to map the underside of the sea ice. Maps were made of three regions of the continent; Weddell, Bellingshausen, and the Wilkes Land. The robot covered an area of 500,000 square metres, the size of 100 football pitches.
Scientist found that the sea ice has an average thickness of between 1.4 meters and 5.5 meters, with some areas having a maximum ice thickness of 17 meters. 76 percent of the ice that was mapped was found to be deformed, this suggests that over the winter period the ice floes repeatedly collided to create a large denser body of ice (“This is in contrast to what scientists previously understood from the Arctic, where larger sections of sea ice, under constant pressure, produce longer linear ‘ridge’ features.“).
Dr. Guy Williams from Institute of Antarctic and Marine Studies adds (co-author on the paper) adds that:
“The full 3-D topography of the underside of the ice provides a richness of new information about the structure of sea ice and the processes that created it. This is key to advancing our models particularly in showing the differences between Arctic and Antarctic sea ice.”
By combining the data from SeaBED, satellite imagery, ice core measures and ship measurements scientist will now be able to form a much better image of what is happening with Antarctic sea ice and calculate better estimates of ice thickness and total sea ice volume.
Dr Jeremy Wilkinson (co-author on the paper) from British Antarctic Survey (BAS) says:
“The AUV missions have given us a real insight into the nature of Antarctic sea ice – like looking through a microscope. We can now measure ice in far greater detail and were excited to measure ice up to 17 metres thick.”
So what next? The scientists want to do large-scale underwater surveys which, can be compared to large-scale observations taken from satellites and aircraft. To get a more complete picture of the whole continent.
Finally, Ted Maksym a WHOI scientist and co-author of the paper lays out the importance of this research and these measurements:
“This work is an important step toward making the kinds of routine measurements we need in order to really monitor and understand what’s happening with the ice and the large scale changes that are occurring.”
I think it is important to remember that this is not counter to climate change taking place and does not mean that ocean and planetary warming is not taking place it just goes to show the variability in climate change worldwide. While this happens in Antarctica the Arctic sea ice is shrinking year on year. This is a very neat study though and is a wonderful development in the ways to monitor and assess sea ice.