The research team utilised remote sensing, remotely controlled boats equipped with specially designed instruments, and helicopter flyovers to map the network of rivers and streams, and collect data on water flow. Alongside the importance of rivers and networks, the study also indicated that discharge from the Isortoq River, one of the largest rivers on the ice sheet, is lower than expected given the amount of water flowing down it. Where and how this ‘missing’ water is being captured under the surface is not yet understood, but is contrary to models used by the Intergovernmental Panel on Climate Change, which assumes all meltwater goes into the ocean. The study will help researchers refine climate models, ultimately developing better global sea level rise projections.
The paper which was published in PNAS is open access.
Image: Supraglacial river networks represent an important high-capacity mechanism for conveying large volumes of meltwater across the Greenland Icesheet surface. Taken direct from the paper.