by Craig Idso
Sundal, A.V., Shepherd, A., Nienow, P., Hanna, E., Palmer, S. and Huybrechts, P. 2011. Melt-induced speed-up of Greenland ice sheet offset by efficient subglacial drainage. Nature 469: 521-524.
According to Sundal et al. (2011), “fluctuations in surface melting are known to affect the speed of glaciers and ice sheets,” but these authors say that “their impact on the Greenland ice sheet in a warming climate remains uncertain,” citing Meehl et al. (2007), while further noting, in this regard, that “although some studies suggest that greater melting produces greater ice-sheet acceleration (Zwally et al., 2002; Parizek and Alley, 2004),” others have identified a long-term decrease in Greenland’s flow despite increased melting (van de Wal et al., 2008).”
In a study designed to further explore this important subject, and based on data for five different years (1993 and 1995-1998), Sundal et al. used “satellite observations of ice motion recorded in a land-terminating sector of southwest Greenland to investigate the manner in which ice flow develops during years of markedly different melting.” So what did they find? (more…)