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

Svalbard -0.12±0.04 m/y

Franz Josef Land -0.08±0.07 m/y

Severnaya Zemlya -0.08±0.05 m/y

Taymir Peninsula

Kara Sea

Putorana Plateau

Novaya Zemlya -0.38±0.06 m/y

Barents Sea

Lyngen

Change in glacier thickness, m/y

+0.50

Polar Urals

-0.50

Figure 4.16 Distribution and recent change in thickness for glaciers in the Barents-Kara Sea region. Colors indicate rate of change in thickness based on ICESat laser altimetry for the period 2003–2009. Glaciers on the Eurasian continent are shown in black, with exaggerated extent for better visibility.

decreased in the south (Käyhkö et al., 2015). While winter and spring discharge have increased in most rivers, there are some indications in northern Lapland that the long-term winter discharge has decreased. One explanation is that the presence of snow is latitude-dependent, but river regulation complicates any interpretation of these trends. Changes in the prevailing air flow over the 20th century has led to changes in river run-off characteristics in the Baltic States (some which overlap with the Barents study area), with increased winter discharge and decreased spring floods. The situation in the Baltic States contrasts with that of the Nordic countries where changes in winter snow melt are not yet apparent (Rasmus et al., 2015). However, future warming is expected to lead to similar cases further north in the Baltic area. An assessment of Norwegian rivers draining into the Barents Sea (Finnmark county), suggest little change over the past 90 years (Hanssen-Bauer et al., 2015). Lotsari et al. (2010) analyzed climate projections and concluded that the flood discharge in the Tana river (average discharge: 203 m 3 /s) draining into the Barents Sea may decline, with spring floods occurring earlier.They also projected that autumnal floods will become more frequent in the future and as a result that their role in sediment transport may also increase. Dankers (2003) suggested that annual discharge from the Tana river may increase by almost 40% under local warming of ~5°C.TheAlta river (average discharge: 90 m 3 /s) and Pasvik river (average discharge: 175 m 3 /s) also drain into the Barents Sea, although

Mountain glaciers on the Eurasian mainland are in rapid decline, and the recent thinning of Langfjordjøkulen near the Barents coast of Norway is stronger than observed for any other glacier in Scandinavia. The Siberian glaciers have few direct observations, but satellite imagery shows considerable glacier area losses over the past decade (Khromova et al., 2014). These mass losses are likely to increase in the future and many of the smaller Russian glaciers are in danger of disappearing completely. Storglaciären in northern Sweden has lost mass since 1992 (Rasmus et al., 2015). The Swedish glaciers respond strongly to changes in climate. Two glacier inventories from northern Scandinavia show a large reduction in ice area between 1973 (321.8 km 2 ) and 2001 (264.5 km 2 ) (Rasmus et al., 2015). More details about climate impacts on land ice are reported in the latest SWIPA assessment (Box and Sharp, 2017). 4.4.4 Fresh water and river ice There has been an observed change in the timing of spring flood associated with changes in the timing of snowmelt (Käyhkö et al., 2015), and ice on waterways is forming later in the season. Earlier break-up dates and shorter periods of ice cover have also been reported. There has been a trend for increased annual river discharge over the period 1961–2000. Over the period 1912–2004, winter and spring discharge in Finland increased most in the north, while summer discharge