Regional characteristics of Arctic temperature variability: comparison of observations with regional climate simulations

Abstract

Regional-scale interannual variability of the seasonal air temperature and the intraseasonal extreme temperature range and their seasonality were investigated for the pan-Arctic and also (in more detail) for Russian Arctic land. Daily mean, minimum, and maximum temperatures were obtained from the 'Global Summary of Day' station data set for the period 1958 to 2008 (51 yr) and from the gridded data of the ERA40 reanalysis and regional climate model HIRHAM simulations for the period 1958 to 2001 (44 yr). Because of a high degree of variability in both temperatures and temperature extremes in the analysis period, it was difficult to identify significant trends. The trends in seasonal temperatures were positive overall, but not significant for the western Russian Arctic. A significant warming in the seasonal temperature was confirmed for the eastern Russian Arctic (0.4 to 0.9°C decade -1 , depending on the season, in the 51 yr station record). Generally, the trends in the seasonal extreme temperature range were of mixed sign and were not statistically significant for the longer record, except for the negative trend of -0.3°C decade -1 for the eastern Russian Arctic in summer. The interannual variability of both temperature measures in turn showed a pronounced decadal variability and considerable regional and seasonal characteristics. The HIRHAM model reproduced the observed temporal evolution and magnitude of the observed temperature variability reasonably well.

Sensitivity of high-resolution Arctic regional climate model projections to different implementations of land surface processes

“…The model covers the area north of 60°N. Several studies recently demonstrated the model's skills at capturing the present-day climate and its variability (Matthes et al 2009;Rinke et al 2010) which gives some confidence in the climate change signals presented here. In the present study, output of the GCM ECHAM5/ MPI-OM (Roeckner et al 2003;Marsland et al 2003) with a resolution of T63(~2°)/L31 for the atmosphere was used as forcing data for the lower and lateral boundaries for the two time slices 1980-1999 (control period) and 2080-2099 (scenario period).…”

A regional climate model hindcast for Siberia: analysis of snow water equivalent

“…Most consider a pan-Arctic domain that includes northern parts of Siberia (e.g., Rinke et al, 2010). Within the SHEBA (Surface Heat Budget of the Arctic Ocean) project, an ensemble was evaluated to quantify the scatter among different RCMs and to assess the reliability of their Arctic simulations (Rinke et al, 2006).…”

Arctic RCM simulations of temperature and precipitation derived indices relevant to future frozen ground conditions

“…The model is configured at a 25 km horizontal resolution and 19 vertical levels. Several studies demonstrated the good model's skill at capturing the present-day air temperature and its spatio-temporal variability (e.g., Matthes et al, 2010;Rinke et al, 2010). Although the model can also reproduce well the observed spatial patterns of the snow water equivalent, it underestimates its magnitude in the Russian Arctic (Saha et al, 2006).…”