Relationships Between Precipitation and Air Temperature with Air Circulation Indices in Nuuk (SW Greenland) from the Late 19th to the Early 21st Century

Abstract

Arctic precipitation plays a key role in driving global climate, ecosystem stability, and the mass balance of glaciers and the Greenland Ice Sheet. The cryosphere is crucial to the evolution of the global climate system. Therefore, this study investigates long-term precipitation changes in southwest Greenland (Nuuk station) and their relationships with air temperature and atmospheric circulation indices, including the North Atlantic Oscillation (NAO) and the Greenland Blocking Index (GBI).

For analysis, several datasets of daily, monthly, seasonal, and annual precipitation totals and mean air temperatures from the Nuuk station were used. Due to data gaps, four climatic subperiods were selected for comparative analysis: (A) 1875–83 and 1886–91 (beginning of precipitation measurements in Nuuk during the Little Ice Age), (B) 1925–27, 1929–32, 1934, and 1936–42 (Early Twentieth-Century Warming), (C) 1970–84 (transition from cooling to contemporary warming), and (D) 2000–14 (recent major warming).

Daily precipitation totals for the earlier periods were digitized from meteorological yearbooks, while later data were obtained from the Danish Meteorological Institute database. Monthly NAO indices from the NSF National Center for Atmospheric Research and GBI indices from NOAA were also used.

Preliminary analyses using statistical methods such as Spearman’s rank correlation coefficients reveal strong relationships between precipitation, temperature, and atmospheric circulation patterns in the Arctic.