Greenland Ice Sheet Surface Hydrology
The Greenland Ice Sheet is currently the largest contributor to sea level rise. Roughly one half of current mass loss in Greenland is caused by surface mass balance; in other words, the difference between the accumulation (snowfall) and ablation (melting). Understanding the processes that control surface melt and how that melt is routed through the ice sheet to the ocean is critical for constraining future sea level rise.
My masters research at the Scott Polar Research Institute focused on supraglacial lakes, which form and drain on the surface of the Greenland Ice Sheet each summer. In particular, I examined rapid lake drainage events, which occur when a crack opens beneath a lake and allows the water in the lake to drain to the bed of the ice sheet, causing a lake disappear very rapidly, often within hours to days. These events may modulate the flow of ice sheets and are therefore a critical and particularly interesting aspect of ice sheet hydrology. My research, published in Journal of Geophysical Research – Earth Surface, found that previous work likely underestimated the occurrence of rapid drainage events due to observation bias caused by frequent cloud cover.
Predicted probably of rapid drainage depending on the observation percentage (i.e. how many times a lake was observed) using different definitions of rapid lake drainage, from 2017 JGR paper.
In addition to my masters research, I also participated in a six-week field campaign at the margin of the Greenland Ice Sheet during summer 2016, where we the studied the evolution of supraglacial streams and the processes controlling ice sheet ablation. Back at Brown, I also was involved in a project led by Jonathan Ryan using MODIS data to map changes in the snowline of the Greenland Ice Sheet published in Science Advances, which found that snowline elevation critically modulates Greenland Ice Sheet melt.
Supraglacial lake on the Greenland Ice Sheet, observed in June 2016.
Related Publications
Ryan, J.C., L.C. Smith, D. Van As, S.W. Cooley, M.G. Cooper, L.H. Pitcher and A. Hubbard (2019), Greenland Ice Sheet surface melt amplified by snowline migration and bare ice exposure, Science Advances. doi.org/10.1126/sciadv.aav3738
Cooper, M.G., L.C. Smith, A.K. Rennermalm, C. Miege, L.H. Pitcher, J.C. Ryan, K. Yang and S.W. Cooley (2018), Near surface meltwater storage in low-density bare ice of the Greenland ice sheet ablation zone, The Cryosphere 12, 955 – 970. doi.org/10.5194/tc-12-955-2018
Cooley, S.W. and P. Christoffersen (2017), Observation bias correction reveals more rapidly draining lakes on the Greenland Ice Sheet, Journal of Geophysical Research – Earth Surface 122. doi.org/10.1002/2017JF004255