Changes in Winter Warming Events in the Nordic Arctic Region

• DOI: 10.1175/jcli-d-15-0763.1
• Publication Date: 2016-05-24T18:27:32Z
• Authors: Dagrun Vikhamar-S...; Ketil Isaksen; Jan Erik Haugen; Hans Tømmervik; Bartlomiej Luks; Thomas Vikhamar S...; Jarle W. Bjerke
• Keywords: Arctic ecology; Arctic dipole anomaly; Siberian High

Abstract In recent years extreme winter warming events have been reported in arctic areas. These are characterized as extraordinarily warm weather episodes, occasionally combined with intense rainfall, causing ecological disturbance and challenges for societies infrastructure. Ground-ice formation due to rain or melting prevents ungulates from grazing, leads vegetation browning, impacts soil temperatures. The authors analyze changes frequency intensity of the Nordic region—northern Norway, Sweden, Finland, including islands Svalbard Jan Mayen. This study identifies longest available records daily temperature precipitation, well future climate scenarios, performs analyses long-term trends indices aimed capture these individual events. Results show high frequencies during 1920s–30s past 15 (2000–14), weak positive over 90 (1924–2014). contrast, strong occurrence all found 50 with, example, increased rates number melt days up 9.2 decade−1 3–7 mainland. Regional projections twenty-first century indicate a significant enhancement For northern Scandinavia, simulations doubling events, compared 1985–2014, while projected 3 times higher.