A Warming Arctic: Regional Drama with Global Consequences

Transcription

1 A Warming Arctic: Regional Drama with Global Consequences Norway: Temperature in March was 3,8 C above the normal, 4th highest since 1900 Monthly precipitation for Norway was 120 % above the normal Temperaturein March in Longyearbyen: 6,7 degrees above the normal Monthly precipitation in March was 334 % of the long term average Jan-Gunnar Winther, director Norwegian Polar Institute

2

3

4 Anomaly ( C) relative to IPCC 2013 Fig. SPM.1a Each of the last three decades has been successively warmer at the Earth s surface than any preceding decade since In the Northern Hemisphere, was likely the warmest 30-year period of the last 1400 years (medium confidence).

5 % (Lüthi et al.,2008, NOAA) The atmospheric concentrations of carbon dioxide, methane, and nitrous oxide have increased to levels unprecedented in at least the last 800,000 years.

6 Polar amplification

7 Arctic summer air temperature Arctic average summer air temperature anomalies for the past 2000 years (relative to the 1961 to 1990 mean), estimated from lake sediments, ice cores, and tree rings. Kaufman et al. (2009), Science c/o AMAP (2011);

8 Arctic summer air temperature: past measurements & year 2100 projections +5.8 C, RCP 8.5 Representative Concentration Pathways (RCPs) yielding projected Greenland average summer air temperature anomalies for year 2100 (relative to the 1961 to 1990 mean), based on IPCC AR5 CMIP5 models (Fettweis et al. 2013) C, RCP Arctic average summer air temperature anomalies for the past 2000 years (relative to the 1961 to 1990 mean), estimated from lake sediments, ice cores, and tree rings.kaufman et al. (2009), Science c/o AMAP (2011);

9 Modelled change in annual mean temperature, Arctic ( relative to ) RCP8.5 RCP to +11 C +2 to +3 C Arctic amplification occurred during the past and is expected in the future Climate models are tested against past climate data Global warming by more than 2 C would be outside of the range of variations of the past million years For comparison, modern woman and man has been on Earth for some years

10 Weather versus Climate

11

12 The Arctic influences climate patterns well beyond the boundaries of the Arctic itself Temperature gradient between mid-latitudes and Arctic weakens Influences jet streams track and speed ( waivier ) Causes slower flow of weather systems, which increases the probability for long-lasting (extreme) weather situations/events Changes distribution of temperature and precipitation patterns

13 Number of «skiing days» (average per year)

14 (from The New North / The World in 2050)

15

16

17 Greenland one of the two giants The average rate of mass loss has very likely increased substantially from 34 [-6 to 74] Gt yr 1 over the period to 215 [157 to 274] Gt yr 1 over the period

18 IPCC 2013 Fig. TS.3 Ice loss from Glaciers 226 (±60%) Gt yr -1 ( ) Greenland 215 (±25%) Gt yr -1 ( ) Antarctica 147 (±50%) Gt yr -1 ( ) 100 Gt yr -1 of ice loss corresponds to 0.28 mm yr -1 of global mean sea level rise

19 IPCC 2013 Fig. SPM.9 RCP2.6 ( ), likely range: 26 to 55 cm RCP8.5 (in 2100), likely range: 52 to 98 cm

20

21

22 Reduction in summer sea ice extent Trend per decade: 13,7 % An accelerating negative trend Large natural variability in the system: Also weather plays a role

23

24 Strong observed decline in multi-year sea ice area NASA

25

26

27 Northern Hemisphere September sea ice extent IPCC 2013 Fig. SPM.7b [...], a nearly ice-free Arctic Ocean in September before mid-century is likely for RCP8.5 (medium confidence).

28

29 Polar basin: Polar basin: High density Low density High density Low density nm nm Plot resolution = 5-7 km depending on area Plot resolution = 5-7 km depending on area

30 New longer term uncertainties Low oil price fuel saving on NSR matters less Pressure for lower escort fees Reduced activity in resource extraction projects in the Russian Arctic loss of customers for NSR General uncertainty about economic development in Russia Reduced income = reduced capacity to develop NSR?

31

32

33

34

35

36 Foto: NINA

37 Changes in food production in 2050 versus 2000 (modelled) due to changes in precipitation and temperature % endring fra år 2000 Müller mfl. (2010) Wheeler & von Braun (2013)

38

39

40 Takk for oppmerksomheten! Thank you for your attention!

41 INTO THE ICE The quest for knowledge at the North Pole

42 In this dynamic and unstable environment our solution was to freeze in research vessel Lance as a floating base camp Longyearbyen Lance Svalbard NORWAY

43

44 Ice motion as seen from the ship s radar

45 2 km