Climate Change: Global and Australian perspectives

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1 Climate Change: Global and Australian perspectives Michael Raupach Centre for Australian Weather and Climate Research ESSP Global Carbon Project with Pep Canadell Thanks: GCP colleagues, CSIRO colleagues, BoM colleagues CSIRO Alumni, Canberra, 18 June 2008

2 Outline Climate projections World Australia Two amplifying feedbacks and one driver Feedback 1: Ice Feedback 2: Carbon cycle Driver: greenhouse gas emissions Responding to the challenge

3 Greenhouse gases in the Earth System Radiatively active (greenhouse) gases: water vapour, carbon dioxide (CO 2 ), methane,... Provide a thermal blanket which keeps the Earth habitable More CO 2, methane,... makes the earth's surface warmer Solar radiation Thermal radiation

4 A changing earth CO 2 emissions Atmospheric CO 2 concentration Global warming Fossil Fuel Emission (GtC/y) Atmoapheric [CO2] (ppmv) Temperature (deg C) Emissions [CO2] Temperature

5 Global CO 2 emissions from fossil fuels Growth rates: : 1.3% y : 3.3% y 1 Actual emissions since 2000 are at upper end of the range of SRES scenarios CO 2 Emissions (GtC y -1 ) Fossil Fuel Emission (GtC/y Actual emissions: CDIAC 450ppm stabilisation 650ppm stabilisation A1FI A1B A1T A2 B1 B2 Recent emissions CDIAC EIA scaled IEAall scaled A1B(Av) A1FI(Av) A1T(Av) A2(Av) B1(Av) B2(Av) Stabilisation 450 Stabilisation 650 Raupach et al. (2007) PNAS Revised for

6 Global average surface temperature to 2100: multi-model average predictions IPCC (2007) WG1

7 Projections of surface temperature in 2025 and 2095 (relative to ) IPCC (2007) WG1

8 IPCC predictions are conservative Temperature Observed increases in temperature and sea level are at the upper end of the range of IPCC (2001) projections Sea level Rahmsdorf, Church et al. (2007) Science

9 Mean annual temperature change: 2030 AGO (2007) "Climate Change in Australia" Baseline = 1990 ( average) Emissions scenarios: Low = B1 Med = A1B High = A1FI

10 Mean annual temperature change: 2050 AGO (2007) "Climate Change in Australia" Baseline = 1990 ( average) Emissions scenarios: Low = B1 Med = A1B High = A1FI

11 Mean annual temperature change: 2070 AGO (2007) "Climate Change in Australia" Baseline = 1990 ( average) Emissions scenarios: Low = B1 Med = A1B High = A1FI

12 IPCC (2007) WG1 Projected patterns of precipitation changes in 2095 Much local uncertainty (< 2/3 of models agree on trend in white areas) Predictions with some confidence: Greenhouse world will be wetter on average Drying in midlatitude regions (including southern Australia) Increased storminess

13 Annual rainfall change: 2030 AGO (2007) "Climate Change in Australia" Baseline = 1990 ( average) Emissions scenarios: Low = B1 Med = A1B High = A1FI

14 Annual rainfall change: 2050 AGO (2007) "Climate Change in Australia" Baseline = 1990 ( average) Emissions scenarios: Low = B1 Med = A1B High = A1FI

15 Annual rainfall change: 2070 AGO (2007) "Climate Change in Australia" Baseline = 1990 ( average) Emissions scenarios: Low = B1 Med = A1B High = A1FI

16 Murray-Darling Basins Flow in the River Murray South-East Coast Basins Murrumbidgee Basin Unimpaired Catchments Major Rivers Gauge at Wentworth Flow since 2002: 24% of pre-2002 mean Rainfall variations are amplified in runoff by about x 3 Murray flow at Wentworth (GL/mth) Flow since 2002: 24% of previous Flow2 mean Data: Murray-Darling Basin Commission, via Geoff Podger, April

17 Upper soil moisture anomalies 2000 to 2007 (bottom to top) Australian Water Availability Project User: awap Password: phase2

18 Subtropical high-pressure ridge over Australia Ridge is intensifying and moving south, more rapidly in recent decades Pressure Latitude MSL pressure 1000 EST Wed 18 June Ridge pressure [mb] Ridge Latitude [deg S]

19 Outline Climate projections World Australia Two amplifying feedbacks and one driver Feedback 1: Ice Feedback 2: Carbon cycle Driver: greenhouse gas emissions Responding to the challenge

20 Decline in Arctic sea ice 1 Std Dev Summer 2007: 3 Std Devs below mean

21 Decline in Arctic sea ice Ice feedback: Warming => less ice => darker surface => more heating => more warming

22 Decline in Arctic sea ice multi-year ice is resilient Not much is left

23 Canadell, Le Quere, Raupach et al. (2007) PNAS Changes in the global CO 2 balance ( ) fossil fuel emissions CO 2 flux (Pg C y -1 ) Sink Source : 45% of total emissions remain in atmosphere deforestation atmospheric CO 2 land ocean Time (y)

24 Present fate of CO 2 emissions 45% to atmosphere increasing 30% to land steady 25% to ocean decreasing Canadell, Le Quere, Raupach et al. (2007) PNAS

25 Raupach et al. (2007) PNAS Drivers of CO 2 emissions Kaya identity: = CO 2 [ ] Per-capita C intensity Population Emission GDP of GDP Per capita GDP Population Emissions Factor Carbon intensity of GDP

26 Outline Climate projections World Australia Two amplifying feedbacks and one driver Feedback 1: Ice Feedback 2: Carbon cycle Driver: greenhouse gas emissions Responding to the challenge

27 The challenge GHG target to avoid dangerous climate change: 500 ppm CO 2 equivalents or less (measured on Kyoto gases) This requires a cap on total global CO 2 emissions for : Cap ~ 500 PgC ~ 500 billion tonnes C as CO 2 To achieve this, decreases in emissions (from 2000 to 2050) must be: ~60% for global emissions ~80% for developed countries including Australia

28 Sharing emissions reduction targets With a 500 PgC cap, the world has 35 years of CO 2 emissions left at current growth rates 1000 w=0 (share by emissions) w=0.5 (compromise) w=1 (share by population) 100 T i [y] USA 55, 35, 13 India 38, 66, 83 World 35, 35, 35 Time to exhaust regional shares of a total 500 PgC (start in 2004 with emissions growing at 2004 rates) 10 USA EU Japan D1 FSU China India D2 D3 World Australia Canada Taiwan KyotoA1

29 Opportunities Next steps Efficient appliances, insulation,... Passive heating, cooling Efficient vehicles Reduced travel (offsets to renewables) Forestry (plant, manage, store, avoid deforestation) Transformations Renewable energy backbone solar, wind, geothermal energy storage (GW-days) Distributed urban energy (use "waste") Redesigning urban energy, transport, water, lifestyles,... Europe's first commercial solar thermal power plant at la Mayor, near Seville, Spain 11 MW, expanding to 300 MW Molten salt heat storage

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31 Five essential response components Science Observe and understand the coupled Earth System (including humans) Technology Broad portfolio: conservation, renewables, cleaner fossil fuels,... Workable transition pathway Innovation! Economy Carbon price signal, carbon trading Policy Global and national caps on emissions Culture and society: building social capital Global: protection of the shared earth system as a global imperative Local: decoupling quality of life from consumption

32 We are starstuff billion-year-old carbon We are golden caught in the devil's bargain Joni Mitchell

33 Notes for Australian climate projections AGO (2007) "Climate Change in Australia" Projections are given relative to the period (referred to as the 1990 baseline for convenience). The projections give an estimate of the average climate around 2030, 2050 and 2070, taking into account consistency among climate models. Individual years will show variation from this average. The 50th percentile (the mid-point of the spread of model results) provides a best estimate result. The 10th and 90th percentiles (lowest 10% and highest 10% of the spread of model results) provide a range of uncertainty. Emissions scenarios are from the IPCC Special Report on Emission Scenarios. Low emissions is the B1 scenario, medium is A1B and high is A1FI.

34 Development trajectories: CO 2 emissions Plot per capita FF emissions against income, in 1980, 1992, 2004 Per capita FF emissions (tc/y/person) F/P Per capita emissions, F/P [tc/y/person] China FSU World India KyA1 Australia Taiwan EU Japan Canada USA USA EU Japan D1 FSU China India D2 D3 World Australia Canada Taiw an KyotoA Income (g=gp/p) Per capita income (k$/y/person, Y2000 US dollars)