Transcript Parry
Water and agriculture in Europe under a changing climate Martin Parry Imperial College London [email protected] Warming is “ “unequivocal” Rising atmospheric temperature Rising sea level Reductions in NH snow cover THE KEY CHARACTERISTICS OF EUROPEAN CLIMATE CHANGE • Annual temperatures increase at the rate of 0.1 to 0.4C/decade • Hot summers will double in frequency by 2020 (increase x5 in S. Spain); 10 times as frequent by 2080 • Summers become drier in S. Europe • Winters become wetter in N. Europe; and intensity of rainfall increases • Additional risks: possibility of change in the Gulf Stream; at present little known about this. Summer Precipitation (only significant changes shown) Acacia project Daily maximum temperatures Number of days per year above 30°C UK Met. Office Present 1 2080s 5 10 20 30 40 50 60 70 80 90 100 200 WATER AVAILABILITY, 2050s (CHANGE IN ANNUAL RUNOFF) Acacia Project WATER AVAILABILITY • Increased availability of water in northern Europe; increased risk of flooding. • Reduced availability of water in southern Europe. • And in the mountains: increased flood risk (20% increase of flood risk in Alps Impacts of reduced Summer rainfall • Reduced summer rainfall will increase risks of: – Irrigation water shortages – Reduced diluting of pollution – Reduced crop yields – Soil loss on light lands – Reduced water cooling for power stations Impacts of winter rainfall increase • Heavier, more intense winter rainfall will increase risks of: – River flooding – Soil leaching – Soil water-logging, – Difficult access to land for animals/machines … Effects on food production Suitability for grain maize cultivation with increasing temperature Expansion of suitable area with increased temperature +5°C +4°C +3°C +2°C +1°C baseline (1961-1990) unsuitable NORTHWARD SHIFDT OF FARMING POTENTIAL Suitability for grain maize, sunflower and soya, 2050s red/brown/blue: suitability extension green/yellow/purple: Baseline 1961-90 PRUDENCE Changes in wheat yield, 2080 (amount of agreement between 9 regional models, A2) Reduced yield in all models Increased yield in all models Models do not agree Dry Danube Croatia - fires France: Several thousand excess deaths HEATWAVE AUGUST, 2003 IN EUROPE UK train tracks buckle COPA Effects of 2003 summer heat wave on EU agriculture France 4000 m € (1500 m € for cattle) Germay 1500 m € Italy 4/5000 m € Spain 810 m € Fodder/cattle Wheat Maize Austria 197 m € -60 -50 -40 -30 -20 Yield change (%) -10 0 10 Farmed landscape, Eastern England, 2000 Increase in renewable energy sources Northward movement of crops Farm-scale biofuel power station Introduction of biofuel crops e.g. Miscanthus spp. Univ of East Anglia, U.K. Farmed landscape,Eastern England, 2050 ? Europe in the context of global climate change Global climate change Global climate change First order impacts on food production First order impacts on food production Second order effects on world prices and demand climate change over Europe Second order effects on world prices and demand Most key impacts stem from reduced water availability. Changes in run-off, 21st century. White areas are where less than two-thirds of models agree, hatched are where 90% of models agree (IPCC SYR) Undefined SI > 75 : Very high SI > 63 : High SI > 50 : Good SI > 35 : Medium SI > 20 : Moderate SI > 5 : Marginal SI > 0 : Very marginal Not suitable Water -100 -88 -75 -63 -50 -38 -25 -13 0 13 25 38 50 63 75 88 100 Suitability for rain-fed cereals (reference climate, 1961-90). Change in suitability for rain-fed cereals (HadCM3-A1FI, 2080s). Cancun agreed Global mean annual temperature relative to pre-industrial 1 2 3 $100 bn target funding Financed adaptation 4 Emissions cuts pledged at Copenhagen Emission peak 2035; T peaks 2100 at c. 3 deg C mitigation Global mean annual temperature relative to pre-industrial 1 2 Impacts not avoided Financed adaptation 3 4 outcome for current pledges Global mean annual temperature relative to pre-industrial 1 2 3 Impacts not avoided Financed adaptation TASK 1 TASK 2 4 outcome for current pledges Conclusions (1) : Effects… • Warmer in the north; drier in the south; intensification of rainfall; increased frequency of extremely hot days or seasons. • This implies more benefits to the north; more “disbenefits” to the south. • Will worsen current resource issues: e.g, more water shortage and heat stress in south; and more flooding in the centre, north and mountains. • May aggravate current environmental problems: eg desertification in south; soil leaching in north. • = a south-to-north geographical shift of climate resources in Europe; increasing the difference in regional resource endowment. Conclusions (2) : Implications for policy in Europe • Need : a) a north-to-south shift of support policies to compensate for shift of climate resources. • Need: b) to “mainstream” climate change into EU policy development: eg i) into environmental policies, such as directives on water, policies on desertification. (This has started). ii) into regional support policies. • In the global context, Europe faces less negative effects than most other parts of the world, implying: a) There may be an opportunity to increase Europe’s share of world food production; b) And, from the global viewpoint, it will be necessary to increase food production in Europe in order to maintain global food security. Programme of Research On Climate Change Vulnerability, Impacts and Adaptation http:// www.provia-climatechange.org THANK YOU! Programme of Research On Climate Change Vulnerability, Impacts and Adaptation http:// www.provia-climatechange.org Professor Martin Parry Grantham Institute, Imperial College London Chair, Pro-Via Interim Scientific Steering Committee