Greenland

Greenland experienced regional warming in 2007, with statistically significant positive (warm) annual temperature anomalies in the 1.3° to 2.7°C range for coastal stations and 1.3°C for the inland ice sheet with respect to the 1971–2000 averages. Seasonal temperature anomalies were largest in winter but not positive in every season. Upper air temperatures indicate lower- to mid-tropospheric warm anomalies in all seasons above sounding stations surrounding Greenland. Noteworthy are western and southern locations where mid-tropospheric anomalies exceed those observed at the surface. Ice sheet surface melt duration anomalies were up to 53 days longer than Figure 5.16. Total annual discharge to the Arctic Ocean from the six largest rivers in the Eurasian pan-Arctic for the observational period 1936–2006 (updated from Peterson and others, 2002) (red line) and from the five largest North American pan-Arctic rivers over 1973– 2006 (purple line). The least squares linear trend lines are shown as dashed blue. 90 the 1973–2000 average, based on passive microwave remote-sensing. MODIS-derived surface albedo anomalies in 2007 versus the 2000–2007 period were persistently negative, consistent with extensive surface melting. Greenland’s largest glacier continued its recession, with ice flushing out from an embayment thought to have been ice filled since at least the onset of the Little Ice Age. The overall ice sheet mass budget was likely in mass deficit by at least 100 km³ yr^–1.