Survey of Greenland instrumental temperature records: 1873-2001

Temporal and spatial variability are analysed in Greenland instrumental temperature records from 24 coastal and three ice sheet locations. Trends over the longest period available, 1873-2001, at Ilulissat/Jakobshavn indicate statistically significant warming in all seasons: 5°C in winter. Trends over the 1901-2000 century in southern Greenland indicate statistically significant spring and summer cooling. General periods of warming occurred from 1885 to 1947 and 1984 to 2001, and cooling occured from 1955 to 1984. The standard period 1961-90 was marked by 1-2 °C statistically significant cooling. In contrast to Northern Hemisphere mean temperatures, the 1990s do not contain the warmest years on record in Greenland. The warmest years in Greenland were 1932, 1947, 1960, and 1941. The coldest years were 1918, 1984, 1993, and 1972, several of which coincide with major volcanic eruptions. Over 1991-2000, statistically significant 2-4°C warming was observed in western Greenland, 1.1 °C warming at the ice sheet summit (3200 m), although this is statistically insignificant. Annual temperature trends are dominated by winter variability. Much of the observed variability is shown to be linked with the North Atlantic oscillation (NAO), sea ice extent, and volcanism. The correlation of coastal temperature anomalies with the NAO is statistically significant, in autumn and winter at western and southern sites. Warming from 1873 to 1930 and subsequent cooling persists after the removal of the NAO signal. Temperature trends are often opposite between west and east Greenland. This apparent teleconnection is spurious, however, given insignificant east-west correlation values. Frequency peaks correspond with periods of 3.7, 14.3, 9.1, 5.5-6.0, 11.1, and 7.1 years in both temperature and NAO.