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How changing climate can effect Pakistan's Agriculture

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2. Shahid Farooq University College of Agriculture, Bahauddin Zakariya University Multan 2 One Day Seminar on Effect of Climate Change on Agriculture Layyah - 31-12-2010 Effect of Climate Change on Agriculture 3. Environment Surrounding of anything that affects its activities is known as environment. Components of Environment Hydrosphere Lithosphere Atmosphere 4. Atmosphere 5. Climate Change: Some Definitions 5 Weather: The state of the atmosphere at a given time and place, with respect to the variables such as temperature, moisture, pressure etc. Climate: Average weather. Statistical description of mean weather conditions over a period of several years, typically 2-3 decades. Climatic elements: precipitation, temperature, humidity, sunshine, wind velocity, phenomena such as fog, frost, and hail storms, and other measures of the weather. 6. Pakistan Climate Pakistan lies in the temperate zone. The climate is generally arid to semi-arid, characterized by hot summers and cool or cold winters, and wide variations between extremes of temperature at given locations. Pakistan has recorded one of the highest temperatures in the world, the hottest of which is recorded in Mohenjo-Daro, Sindh, 53.5 C (128 F) on 26 May, 2010 it is not only the hottest temperature ever recorded in Pakistan, but also the hottest reliably measured temperature ever recorded in the continent of Asia. 7. Our Climate is Changing During the last century, the atmospheric concentration of greenhouse gases have continued to rise as a result of human activities. Global average surface temperatures have increased by about 0.6 C. Global average sea level has risen about 15 cm in the previous century and ocean heat content has increased. There is new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities (IPCC, 2001) CO2 Concentrations and Global Average Temperatures Will Continue to Rise Pre-industrial level: 280 ppm Current level: 360 ppm Level in 2100: ~700 ppm with large uncertainty Source: IPCC, 2001 8. Heat Trapping Mechanism The sunlight mainly consists of 3 types of radiations Ultraviolet, Visible (PAR) and Infrared Infrared rays are heat rays and if trapped cause heating of earth and its atmosphere. When IR are emitted from extremely hot bodies like sun are of short wavelength and cant be absorbed by CO2 and even glass sheet. When IR are emitted from less hot bodies like earth surface or bodies present on earth, are of longer wavelength and can be absorbed by CO2 molecules and other gases present in the atmosphere. Harmful UV rays are absorbed by Ozone layer and most of it dont reach earth surface. 9. Green House Effect The heating of earths atmosphere due to absorption of IR radiations reflected from earths surface by green house gases in atmosphere. These gases are CO2, Methane, Nitrogen oxides, Chlorofluorocarbons, water vapors, Ozone etc. CO2 57% Methane 12% Nitrogen Oxides 6% Chlorofluorocarbons 12% Water vapors and Ozone 5% 10. 10 343 W/m2 30% 11. Greenhouse Effect The Greenhouse Effect plays a crucial role in maintaining a life-sustaining environment on the Earth; If there was no Greenhouse Effect, the average temperature of the Earth would have been -18oC (253K) instead of the present 15oC; Human activity is enhancing the natural Greenhouse Effect by adding gases like carbon dioxide, methane, nitrous oxide, chlorofluorocarbons, ozone, etc; It is this Enhanced Greenhouse Effect which is causing Global Warming and Climate Change. 12. Who Causes the Climate Change!! We do!!! We send greenhouse gases to the atmosphere. Industrial practices; cars, planes, factories, electricity, and solid trash. Environmental practices; deforestation, and pollution. 13. Carbon Dioxide Concentrations 14. Why Climate is Changing??? Deforestation Cultivation of land Industrialization Automobile revolution Urbanization Fossil fuel combustion Population Explosion Refrigerators Chl0rofluorocarbons (CCl3F, CCl2F2) Rockets, Jets sent into space (Each rocket releases 75- 150 tones of Chlorine). 15. Role of Agriculture in Climate Change Emission of green house gases from crops Cultivation of land Intensive agriculture practices Use of chemical fertilizers Use of Pesticides Respiration activities Burnings of straws, stubbles etc. Decomposition of Organic Matter Anaerobic rice cultivation Livestock activities 16. 1.17 70% of global N20 emissions from artificial fertilizers 50% of global methane emissions from rice paddies Agricultural Sector Contributes 20% of global anthropogenic GHG emissions 5% of global CO2 emissions from fossil fuel consumption and biomass burning 17. Natural Climate Variability Anthropogenic Influences since the Industrial revolution CLIMATE CHANGE Global Warming Increased Precipitation & its Uneven Distribution Melting of Glaciers & Snow Sea level Rise Increase in Frequency & Intensity of Extreme Weather Events IMPACTS Uncertainty in Water Availability Decrease in Crop Yields Newer perspective for sources of energy Loss of Biodiversity Increased Health Risks Spiraling Population High pace of Industrialization Increasing use of Fossil Fuels in Industry & Transport Deforestation for Agriculture and Urbanization Climate Change Natural + Anthropogenic 18. Future Impacts of Climate Change Severe stress on natural ecosystems Expansion of Earths deserts Melting of the polar ice caps and rise in sea level More extreme weather events Loss of Biodiversity Movement of Traditional agriculture areas Species extinction Decrease of human health and living standards 19. Future Impacts of Climate Change Food Shortage Heavy floods Increase in salinity level Water logging Drought, Water shortage Acid Rains Ozone Depletion 20. Millions at Risk (Parry et al., 2001) 15 September 2006 IEF climate conference 22 21. Impacts of Climate Change on Agriculture Beneficial effects (Lengthen the growing season in cool areas Loss in yield Disturbance of cropping patterns Uneven distribution of precipitation Dangers of floods causing loss of agriculture crops Water shortage Occurrence of drought Increase in salinity Increase in water logging Stunted growth due to oxides of nitrogen and fluoride Increase in evaporation rate 22. Adversely affect crops in heat limited areas Change the life cycle of oilseeds and grains Migration of weeds Climate change may alter the world's habitats and ecosystems. Life depends on a delicate balance of rainfall, temperature, and soil type. Global Warming could upset this balance and seriously endanger many living things. Climate Change used to occur slowly, allowing plants and animals to adapt to the new environment or move somewhere else. However, if future climate changes occur as rapidly as some scientists predict, plants and animals may not be able to react quickly enough to survive. 23. Vulnerability of Water Resources to Climate Change Increased variability of Monsoon More rapid melting of Glaciers threatening IRS Flows Shortage of irrigation water for agriculture, water for industrial and domestic sectors. Increased risks of floods and droughts 24. Melting of Glaciers in Pakistan Glaciers are life line of Pakistani rivers. The total water storage in glaciers in Upper Indus Basin (UIB) is 2,200 MAF Melt water from these Glaciers contributes more than 60% to the flows from UIB. International Commission for Snow and Ice (ICSI) (1999): Glaciers in Himalayas are receding faster than in any other part of the world and, if the present rate continue, the likelihood of them disappearing by the year 2035 is very high. World Bank (2006): Western Himalayan glaciers will retreat for the next 50 years causing increase of Indus River flows. Then the glacier reservoirs will be empty, resulting in decrease of flows by up to 30% to 40% over the subsequent fifty years. 25. 28 Qori Kalis Glacier, Quelccaya Ice Cap, Peru, 1978 2002 26. GLOFS in Pakistan As glaciers retreat, glacial lakes form behind moraine or ice 'dams. These can breach anytime leading to floods known as Glacial Lake Outburst Floods (GLOFs) which can destroy: property, farms, socio-economic infrastructure and livelihood of mountain people and downstream communities. 29 27. There is an urgent need to Assess Pakistans glaciers, future water resources and storage requirements in the wake of climate change threat Take appropriate ameliorative measures well in time to avoid calamites. 30 The Water Challenge: Conclusion 28. Food Security Challenge 29. Agriculture Systems in Pakistan Irrigated Agriculture Consumes >90% of fresh water resources and contributes >80% to national production Rained and Dry land Agriculture Contributes

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