Year 2011 Greenland melting remains well above the (1979 \textendash 2010) average; close-to-record mass loss

Melting in Greenland in 2011 was still above the average (1979 \textendash 2010 baseline period), exceptionally high over the west coast and reaching close-to-record simulated surface mass balance, bare ice exposure, albedo and runoff anomalies. The melting index (e.g., the number of melting days times the area subject to melting) in 2011 estimated from spaceborne microwave observations using the approach in (Tedesco, 2007) did not break the previous record set in 2010 (e.g., Tedesco et al., 2011). However, 2011 is positioning itself 6th in terms of melting index, after 2010, 2007, 1998, 2002, 2005. An alternative approach using microwave data as well (Mote and Anderson, 2005) indicates that melt extent for the period June through August 2011 ranked third since 1979, following 2010 and 2007. Satellites data cannot produce estimates of runoff and liquid water content. However, these can be analyzed by means of models. The model used in this analysis (MAR, e.g., Tedesco et al., 2011) indicates that 2011 was comparable to the record season of 2010 with respect to runoff, surface mass balance, albedo and bare ice exposure. Strong negative surface mass balance anomalies occurred in 2011, according to MAR (e.g., the loss in 2011 and 2010 were much higher than the gained mass because of accumulation). Surface albedo simulated by MAR was consistently below or around 2 standard deviations below the mean for the period June \textendash August (e.g., more solar radiation absorbed supporting more melting, see Figure 4 for a diagram). The bare ice area exposed during the summer of 2011 was also large with respect to the mean (close to up 3 standard deviations for the month of July), similarly to what happened in 2010.