CLIMATE AND ENVIRONMENTAL CHANGE

Transcription

1 CLIMATE AND ENVIRONMENTAL CHANGE M.Sc. Module Global Transformation and Environmental Change Prof. Dr. Jürgen Scheffran & Prof. Dr. Udo Schickhoff with slides provided by Prof. Dr. Jürgen Böhner Lecture 5 Prof. Dr. Jürgen Scheffran Abteilung Integrative Geographie, Universität Hamburg Research Group Climate Change and Security Grindelberg 7, Room 2015 (Sprechstunde nach Vereinbarung) Tel: juergen.scheffran@uni-hamburg.de Web: 1

2 CLIMATE AND ENVIRONMENTAL CHANGE M.Sc. Module Global Transformation and Environmental Change Part A: Climate and Environment Jürgen Scheffran I II III Introduction The Climate System Climate Change IV Climate and Environmental Change Part B: Human Impact on World Vegetation Udo Schickhoff

3 Climate Change Impact Hydrosphere Findings of the AR4 (IPCC 2007) Consequences of Climate Change for Fresh Water Availability (IPCC 2007): It is projected with very high confidence that: Dry regions are projected to get drier, and wet regions are projected to get wetter: By mid-century, annual average river runoff and water availability are projected to increase by 10-40% at high latitudes and in some wet tropical areas, and decrease by 10-30% over some dry regions at mid-latitudes and in the dry tropics. Drought-affected areas will become larger. Heavy precipitation events are very likely to become more common and will increase flood risk. Water supplies stored in glaciers and snow cover will be reduced over the course of the century

4 Hydrosphere Climate Change Impact Hydrological Circle Multi-model mean changes in components of the water balance (IPCC 2007)

5 Climate Change Global mean precipitation versus temperature changes relative to Source: IPCC 2013, AR5-WG1

6 Climate Change Multi-model projections of zonal precipitation changes (CMIP5) Mean precipitation Zonal precipitation minus evaporation Source: IPCC 2013, AR5-WG1

7 Climate Change Temperature and precipitation change patterns Source: IPCC 2013, AR5-WG1

8 Geographical ranges of temperature extremes Climate Change Source: IPCC 2013, AR5-WG1

9 Climate Change Return times for precipitation-induced floods aggregated over England/Wales 2010 Russian heat wave Source: IPCC 2013, AR5-WG1

10 General Oceanic Circulation Ocean Dynamics The ocean as carbon sink 10

11 Anomalies in the ocean CO2 ocean-to-atmosphere flux inclimate responseimpact to: Assessment (a) changes in climate, (b) increasing atmospheric CO2 and (c) the combined effects Source: IPCC 2013, AR5-WG1

12 Climate Change Impact Cryosphere Glacier mass balance and atmospheric circulation Equilibrium line: elevation at which accumulation and melting of glacier ice are equal.

13 Cryosphere Climate Change Impact Components of the Cryosphere Area, volume and sea level equivalent (SLE) of cryospheric components. Indicated are the annual minimum and maximum for snow, sea ice and seasonally frozen ground, and the annual mean for the other components. The sea ice area is represented by the extent (area enclosed by the sea ice edge). The values for glaciers and ice caps denote the smallest and largest estimates excluding glaciers and ice caps surrounding Greenland and Antarctica (IPCC 2007).

14 Climate Change Impact Cryosphere Mass balance (WGMS 2008) The cumulative mass balance curves (meter water equivalent) are shown for the mean of all glaciers and 30 reference glaciers with (almost) continuous series since 1976

15 Climate Change Impact Cryosphere Glacier length changes (IPCC 2007) Large-scale regional mean length variations of glacier tongues. The raw data are all constrained to pass through zero in 1950 (IPCC 2007) Glaciers are grouped into the following regional classes: SH (tropics, New Zealand, Patagonia), northwest North America (mainly Canadian Rockies), Atlantic (South Greenland, Iceland, Jan Mayen, Svalbard, Scandinavia), European Alps and Asia (Caucasus and central Asia)

16 Cryosphere Climate Change Impact Sea Ice Arctic Hadley September ice extent ( ) with alternative fits (WALTER et al. 2007)

17 Climate Change Impact Cryosphere Glacier length changes (WGMS 2008) Temporal overview on short-term glacier length changes. The number of advancing (blue) and retreating (red) glaciers are plotted as stacked columns in the corresponding survey year

18 Climate Change Impact Cryosphere Glacier length changes (WGMS 2008) Temporal overview on short-term glacier length changes. The number of advancing (blue) and retreating (red) glaciers are plotted as stacked columns in the corresponding survey year

19 Climate Change Impact Cryosphere Glacier length changes - Examples Morteratsch Seit Beginn der systematischen Beobachtungen im Jahr 1878 hat der Gletscher 2,2 Kilometer an Länge eingebüsst. Mit rund 6,4 Km ist er der drittlängste Gletscher der Ostalpen

20 Climate Change Impact Cryosphere Glacier length changes - Examples Vadret Pers

21 Climate Change Impact Cryosphere Glacier length changes - Examples Grosser Aletschgletscher um

22 Rhonegletscher around

23 Climate Change Northern Hemisphere near-surface permafrost area Source: IPCC 2013, AR5-WG1

24 Climate Change Simulated area of Northern Hemisphere permafrost in upper 3 m of soil Source: IPCC 2013, AR5-WG1

25 Changes in sea ice extent in Northern and Southern hemisphere Climate Change Source: IPCC 2013, AR5-WG1

26 Climate Change September Arctic sea ice extent as a function of surface warming Source: IPCC 2013, AR5-WG1

27 Cryosphere Climate Change Impact Sea Ice Multi-model mean sea ice concentration (%) for January to March and June to September in the Arctic and Antarctic for the SRES A1B scenario (IPCC 2007)

28 Cryosphere Climate Change Impact IPCC Findings Mountain glaciers and snow cover have declined on average in both hemispheres. Losses from the land-based ice sheets of Greenland and Antarctica have very likely (>90%) contributed to sea level rise since Ocean warming causes seawater to expand, which contributes to sea level rising. Antarctic sea ice shows no significant overall trend, consistent with a lack of warming in that region. Sea ice is projected to shrink in both the Arctic and Antarctic In some projections, Arctic late-summer sea ice disappears almost entirely by the latter part of the 21st century. Multi-model mean sea ice concentration (%) for January to March and June to September in the Arctic and Antarctic for the SRES A1B scenario (IPCC 2007)

29 Climate Change Climate-sensitive processes and components of sea-level change Source: IPCC 2013, AR5-WG1

30 Climate Change Impact Hydrosphere: Sea-level change Ocean warming causes seawater to expand, which contributes to sea level rising. Sea level rose at an average rate of about 1.8 mm/year during the years The rise in sea level during was at an average rate of 3.1 mm/year. It is not clear whether this is a long-term trend or just variability. Consequences of Climate Change for Costal Systems with very high confidence Coasts will be exposed to increasing risks such as coastal erosion due to climate change and sea-level rise Increases in sea-surface temperature of about 1-3 C are projected to result in more frequent coral bleaching events and widespread mortality unless there is thermal adaptation or acclimatisation by corals Many millions more people are projected to be flooded every year due to sea-level rise by the 2080s.

31 Past data and future projections of global-mean sea level rise for RCP2.6 (blue) and RCP8.5 (red) scenarios Source: IPCC 2013, AR5-WP1

32 Ensemble mean net regional sea level change from 21 CMIP5 models for different RCP scenarios between and Source: IPCC 2013, AR5-WP1

33 Climate Change Map of rates of change in sea surface height Source: IPCC 2013, AR5-WG1

34 Climate Change Likely ranges and median values for global mean sea level rise Source: IPCC 2013, AR5-WG1

35 Climate Change Impact Cryosphere Mass balance (IPCC 2007) Greenland ice sheet melt area increased on average by 16% from 1979 to The smallest melt extent was observed after the Mt. Pinatubo eruption in 1992

36 Disintegration of West Antarctic Ice Sheet (WAIS) The WAIS may disintegrate in response to anthropogenic greenhouse gas emissions (Oppenheimer 1998). Warming of 2.5 o C as a WAIS climate limit. Consequences of WAIS collapse: global sea level rise of around 6 meters, disruption of global oceanic circulation patterns.(keller 2005) Two possible positive feedbacks: slip rate -> bottom temperature -> slip rate temp. -> melting rate -> height -> temp.

37 Ice loss for Antarctica, Greenland and glaciers ( ) Source: IPCC 2013

38 Basin-integrated sea-surface height (SSH) anomalies from Greenland run Source: D. Stammer (2008)

39 Surface freshwater flux anomalies Greenland Antarctic Surface freshwater flux anomalies (in m3/s) per model grid point associated with the mass loss of polar ice sheets and added to the NECEP/NCAR net freshwater forcing after division by the surface area of each grid cell Source: D. Stammer (2008) Response of the global ocean to Greenland and Antarctic ice melting

40 December-mean anomalies of SSH from enhanced Greenland freshwater forcing Source: Stammer (2008)

41 December-mean salt anomalies at different years and depths from Greenland Practical Salt Units (PSU): conductivity ratio of a sea water sample to a standard KCl solution Source: Stammer (2008)

42 December-mean anomalies of SSH resulting from a freshwater source around Antarctica Source: D. Stammer (2008)

43 General Oceanic Circulation Ocean Dynamics Thermohaline circulation 43

44 Ocean Dynamics General Oceanic Circulation Possible impacts of a THC shutdown (Kuhlbrodt et al., 2009) 44

45 Climate Change Multi-model mean of projected change in sea surface temperature and salinity Source: IPCC 2013, AR5-WG1

46 Climate Change Projected change in temperature & Atlantic meridional overturning circulation 1 Sverdrup (Sv) = a flow of ocean water of 10 6 cubic meters per second Source: IPCC 2013, AR5-WG1

47 Climate Change Multi-model projections of Atlantic Meridional Overturning Circulation at 30 N Source: IPCC 2013, AR5-WG1

48 Meridional sections of potential temperature anomalies from year 30 (a) 30W in the Atlantic Ocean (c) 180E in the Pacific Ocean Source: Stammer (2008) (b) 80E in the Indian Ocean

49 Climate Change Projected alteration of oceanic fluxes and atmospheric events Source: IPCC 2013, AR5-WG1

50 Climate Change Estimated global mean temperature response based on GTP Source: IPCC 2013, AR5-WG1

51 Climate Change Cumulative land and ocean carbon uptake simulated Source: IPCC 2013, AR5-WG1

52 Climate Change Estimated global mean temperature response based on GTP Source: IPCC 2013, AR5-WG1

53 III CLIMATE CHANGE Climate Change Global carbon cycle with typical turnover time scales for carbon transfers through major reservoirs Source: IPCC 2013, AR5-WG1

54 Climate Change Proportion of global land cover occupied by different land uses Source: IPCC 2013, AR5-WG1

55 Climate Change Projections of climate change-driven biome shifts in the context of land use Source: IPCC 2013, AR5-WG1

56 Climate Change The Kaya Identity Equation Greenhouse Gas Emissions G = Emission Intensity G/E x Energy Intensity E/W x Labor Productivity W/P x Population P G = (G/E) * (E/W) * (W/P) * P = g * e * w * P P is population G is greenhouse gas emissions of this population (e.g. CO2) W is the wealth of the population (GDP) E is the primary energy consumption of the population w = (W/P) is per-capita wealth (labor productivity) e = (E/W) is the energy intensity of wealth (GDP) g = (G/E) is the carbon intensity of energy. Source: IPCC 2013, WG1

57 Climate Change Distribution of regional GHG emissions in relation to population and GDP (excluding international transport) Cumulative distribution of GHG emissions per capita NAM: North-America, POECD: Pacific Organisation for Economic Co operation & Development, EIT: Eastern Europe & former Soviet Union, WEU: Western EU, EAS: East Asia, MNA: Middle East & North Africa, South East Asia & Pacific (PAS), LAM: Latin America, SSA: Sub-Saharan Africa, SAS: South Asia Cumulative distribution of GHG emissions per GDP Source: IPCC 2014, WG-3

58 Climate Change Decomposition of global energy-related CO2 emission changes IPCC 2007: WG-3 TPES: Total Primary Energy Supply GDP-ppp: Income by purchasing power parity

59 GHG emissions per region and capita Climate Change IPCC WG-3 (2014)

60 Climate Change Factor decomposition of fossil energy CO2 emissions at regional level IPCC WG-3 (2014)

61 Climate Change Historical regional trajectories of territorial fossil energy CO2 emissions vs. GDP ( ) IPCC WG-3 (2014)

62 Climate Change Regional and national trends in population and GHG emissions IPCC WG-3 (2014)