Adaptation Actions for a Changing Arctic: Perspectives from the Barents Area

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Adaptation Actions for a Changing Arctic: Perspectives from the Barents Area

4.2.2 Precipitation Extreme precipitation can have major impacts on Arctic communities, especially when it falls as rain on snow and then freezes to form ice (Hansen et al.,2014).Changes in precipitation are expected to include greater amounts,changes in the frequency of occurrence,and a shift in the relative proportions falling as rain and snow (Førland and Hanssen-Bauer, 2003).There have been various efforts to project future precipitation since the previous

IPCC assessment (AR4), and there are indications that the maximumincrease inmarine precipitationmay take place over the Barents andKara seas (Overland et al.,2011).Previous projections for these two areas suggested an increase inprecipitationof 9–39% between1980–1999 and2080–2099,under the SRESA1B scenario (IPCC, 2000). However, more recent projections suggest much stronger increases, of the order of 50% in the Arctic region, which is among the highest globally (Bintanja and Selten, 2014). This corresponds to an increase of 2–10 mm per month, and

Absolute sensitivity

Relative sensitivity

DJF

M-CC=2.4 mm/month/°C

M-CC=3.94 %/°C

MAM

Relative precipitation sensitivity, % / °C

Absolute precipitation sensitivity, mm / month / °C

10 12 14 16 18 20 22

10 12 14 16 18 20 22

M-CC=1.96 mm/month/°C

M-CC=4 %/°C

0 2 4 6 8

0 2 4 6 8

JJA

M-CC=3.29 %/°C

M-CC=1.87 mm/month/°C

-2 -4 -6 -8

-2 -4 -6 -8

-20 -22 -18 -16 -14 -12 -10

-20 -22 -18 -16 -14 -12 -10

SON

M-CC=4.55 %/°C

M-CC=3.66 mm/month/°C

Figure 4.4 Calculated seasonal precipitation sensitivity over the Barents and Scandinavian region using the regional climate model COSMO-CLM driven by the global MPI-ESM-LR Earth SystemModel.Absolute (left) and relative (right) sensitivities following the RCP8.5 scenario for the period 2071–2100 relative to 1971–2000. Numbers at the lower right of each plot give the mean precipitation sensitivity over the domain shown (Dobler et al., 2016).