Climate Change, Agriculture and Sustainable Development Dr. S. M. Talekar Head, P. G. Dept. of Botany Mrs. K. S. K. College Beed 1
What is climate ? • Climate is an average of weather (Temperature, Rainfall. . . ) over a “long” time (more than 2 -3 weeks). • Climate encompasses the temperatures, humidity, atmospheric pressure, winds, rainfall, atmospheric particle count and numerous other meteorological elements in a given region over long period of time. • The pattern or cycle of weather conditions such as temperature, wind, rain, snowfall, humidity, clouds, including extreme or occasional ones, over a large area, averaged over many years. • Climate is how weather acts over many years. 2
Types of climates in India 3
Seasons in India • Winter is Shishir (December to February) • Summer is Greeshm (March to may) • Monsoon is Varsha (June to September ) • Post-monsoon is Sharad (October and November) 4
What is climate change? • The climate change problem is related to changes in the concentration of the greenhouse gases (water vapor, CO 2, CH 4, N 2 O, and CFCs), which trap infrared radiation from the Earth's surface and thus cause the greenhouse effect. • This effect is a natural phenomenon, which helps to maintain a stable temperature and climate on Earth. • Human activities, such as fossil fuel combustion, deforestation, and some industrial processes have led to an increase in greenhouse gases concentration. 5
• Climate change is a study dealing with variations in climate on many different time scales from decades to millions of years. • In the most general sense, the term "climate change" encompasses all forms of climatic inconstancy i. e. any differences between longterm statistics of the meteorological elements calculated for different periods but relating to the same area. • The term "climate change" is often used in a more restricted sense, to denote a significant change such as a change having important economic, environmental and social effects in the mean values of a meteorological element (in particular temperature or amount of precipitation) in the course of a certain period of time. 6
What makes the climate change? 7
• Factors primarily responsible are • Variations in the Earth's orbital characteristics. • Atmospheric carbon dioxide variations. • Volcanic eruptions. • Variations in solar output. • • Industrialization Green house gases Land use change Sulfates aerosol and Black carbon • Some cause bigger changes, some cause small changes • Some cause slower changes, some cause fast changes • Some cause changes that last, some cause changes that go away fast 8
How has climate changed in the past? § Ice Ages Big swings in climate over 1, 000 yrs occurred over last million years. ● Advance and retreat of ice sheets. ● Global mean temperature has increased by 0. 740 C. ● Global average sea level increased at avg. rate of 1. 8 mm / yr. over 1961 to 2003. About 3. 1 mm / yr over 1993 to 2003. • Cold days, nights and frost are less frequent, hot days, hot nights and heat waves are more frequent. ● 21 thousand years ago Now 9
Human caused climate change: the Green House Effect Global warming 10
Rising trend in Temperature caused by CO 2 increase 11
Global mean temperatures have increased by 0. 74 o. C during last 100 years. The rate has become faster in recent years Source: IPCC, 2007 12
Future Climate • Although there is considerable uncertainty about future, all climate models indicate a rising trend in temperature. By 2100 a rise of 1. 8 to 4 o. C is expected. • Higher values cannot be ruled out. 13
Build-up of atmospheric carbon dioxide over time 14
Observed Changes in Sea Surface Temperatures NATL = North Atlantic WPAC = West Pacific SPAC = South Pacific EPAC = East Pacific NIO = Northern Indio SIO = Southern Indio 15
Changes in Sea Level since 1850 and Projection (IPCC 4 th AR, WGI, Paris, 5. 2. 2007) 16 Global average sea level has risen since 1961 at an average rate of 1. 8 mm / yr and since 1993 at 3. 1 mm / yr
Sea Level Rise - Observations Sea level increase by ~ 1. 3 mm / year Unnikrishnana et al. Curr. Sci, 90, 365 -372, 2006 17
Glacier melting in the Himalayas • Receding of 7. 3 m per year between 1842 and 1935; • 2. 3 m per year between 1985 and 2001 • Rock Avalanches • Glacier Lake Outburst Flows • Less water downstream in the dry season • More flooding downstream in the wet season • Long-term overall reduction of water supply 18
What will the future climate look like? The south Cascade glacier retreated dramatically in 20 th centaury 1928 2000 Courtecy of the USGS glacier group 19
How will climate change affect people? 20
21
Impacts of climate change • • Extreme weather events (abrupt swings). More frequent and powerful cyclones and hurricanes, More frequent and intense floods and heavy snowfalls, Severe and longer drought periods, Unexpected climatic events, Changes in Weather Patterns, Short winters, earlier spring and longer summers. 22
India and agriculture • Population : 1 billion + • GDP from Agriculture : 34 % (1994), 42 % (1980) • Area under Agriculture : 50 % (160 mha) • Population dependent on Agriculture : 70 % • Average farm size: : 1 to 5 ha • Landless dependent on others Production of wheat and rice : T. Area Irrigated Prod Earnings % of GDP (mha) (mt) (Rs. ) Rice 42 20 73 Wheat 24 21 57 365 22 208 12. 6 23
Effects on Agriculture : • Direct effect : 1. Change in temperature 2. Precipitation 3. Radiation 4. CO 2 concentration • Indirect effects : 1. Change in soil 2. Infestation by pest 3. Diseases 24
• 1997 K. J. Henessey, Scientist, Commonwealth Research Organisation, Australia by mathematical modeling and empirical observations suggested global warming leads to rainfall and flood. • Centre for Mathematical Modeling and Computer Simulation, Bangalooru reported dry areas like S. Gujarat, N. Madhya Pradesh and S. Orissa receiving extreme rainfall. 25
• The Third Assessment Report (TAR) of IPCC indicates that wheat and rice production will drop. 1. 50 C rise in temperature and 2 mm increase in precipitation will decline rice yeild by 15 %. • Kumar and Parikh, 1998 2 - 3. 50 C rise in temperature loose 9 – 25 % in net revenue at farm level. • Sanghi, Mendelson and Dinar, 1998 20 C rise in temperature and 7 % increase in precipitation reduce net revenue by 12. 3 %. 26
Heavy precipitation events over Central India have increased during last 50 years Light to moderate rainfall events (5 -100 mm) Heavy rainfall events (>10 cm) Very heavy rainfall events (>15 cm) Source: IITM, Goswami et al. 2006; data is the frequency in each of 143 grids in the region 27
How could we relate these rainfall with Global Warming : Tirupati based National Atmospheric Research Laboratory published a research paper in Geophysical Research Letters journal on Sept. 20, 2008 28
Some events of heavy rainfall : July 26, 2005 : 944 mm rainfall flooded Mumbai. Paddy and Sugarcane on 90, 000 ha were destroyed. September 2, 2006 : 577 mm of rain in Barmer dist. of Rajasthan over 3 days. More than twice rainfall of average. Farmers lost crops worth Rs. 1300 crores and 75, 000 farm animals. June 28, 2008 : Mahasamund dist. Chhattisgarh, 183 mm rain in one day followed by dry spell for 26 days. 5 sacks of rice instead of 55 sacks. August 27, 2008 : 110 mm Anantpur dist. Andhra Pradesh in a single day instead 0 f 89 mm rain for entire August. Groundnut crop was destroyed. 29
World wide impacts of rise in sea level : • Large part of the world’s population has always lived in the low-lying coastal areas. • The presence of fertile soil and fishing waters and ready accessibility of these areas have always held a great power of attraction over people. • About 10% of world’s population lives near the coast. • Two –Third of these coastal areas has a relatively low population density. • Developing countries are strongly dependent on the river deltas for their food production. • These areas will be partly inundated at a sea level rise of one meter causing the water to become brackish. 30
Sea turns its heat on rains : • As the climate warms in response to increase in green house gases, evaporation from the sea surface also takes place at a faster rate. • This increases water vapor content in the atmosphere that condenses and falls as intense rain when the temperature cools down. • When this vapor condenses and falls as raindrops, the heat trapped within is released and warms the air close to earth surface, which has compound effect leading to more vaporization. • Increase in average wind speed over the sea surface too has contributed to temperature increase. 31
Effect of temperature rise on agriculture : • Wheat production in India has fallen four to six million tones over the past eight years due to increase in temperature in February and March. • Apple growing of Himachal Pradesh has shifted from Shimla and Kullu where temperatures have risen to Lahaul and Spiti. • Rise in temperature dries up the soil and increases water requirement of crops. • Initial increase in CO 2 levels enhances photosynthesis and crops grow fast. But the temperature increase due to higher CO 2 level stalls growth of plants. 32
Projected impacts of climate change on Indian agriculture : q CO 2 fertilization benefits = < 10% average. q In short-term, impacts of mean changes in climate are likely to be small. q In long run, impacts are likely to be large. Crop productivity to decrease by 10 - 40% by 2100. q Some improvement in chickpea, mustard; rabi maize, sorghum and millets; and coconut in west coast; less frost damage in potato, peas, mustard. q Impact on livestock, fisheries and pests. q Impact on food trade. 33
Managing increasing climatic variability is likely to be difficult but is critical • Increased frequency of short episodes of – droughts – floods – heat • These are likely to significantly increase production variability. 34
Traditional adaptations / coping strategies to climatic stress practiced by farmers • Drought proofing by mixed cropping. • Changing varieties / crops / planting time: matching crop phenology with weather / water availability. • Diversifying income sources including livestock raising. 35
Limitations of available adaptation strategies : – Limited local relief. – Time lag in responses at all scales § Availability of seeds of adapted varieties and other technologies at a short notice § Once planted, only limited relief is possible § Unpredictable extreme events complicate further – Need for other adaptation strategies. 36
Adaptation strategies to climate change in agriculture : n Assist farmers in coping with current climatic risks n Intensify food production systems n Improve land water management n Enabling policies and regional cooperation n Strengthen research for enhancing adaptive capacity and mitigation potential 37
Adaptation strategies in agriculture: contd… • Assist farmers to cope with current climatic risks • Establishing an early warning system of climatic risks / disasters • Promoting insurance for climatic risk management • Strengthening pest surveillance and forecasting mechanisms 38
Adaptation strategies in agriculture: • Assess regional impacts on crops, livestock, fisheries, pests, and microbes • Evolve ‘adverse climate tolerant’ genotypes and land use systems • Re-examine water and fertilizer management for adaptation and mitigation • Study dynamics of pest movements and virulence • Strengthen research on adaptation 39
Solution for sustainable development Carbon capture and storage • Introduce systems to capture CO 2 and store it underground at 800 large coal-fired plants or 1600 natural gas fired plants. • Use capture systems at coal-derived hydrogen plants producing fuel for a billion cars. • Use capture systems in coal derived synthetic fuel plants producing 30 million barrels a day. 40
Renewable and Biostorage • Increase wind-generated power to 25 times current capacity. • Increase solar power to 700 times current capacity. • Increase ethanol biofuel production to 50 times current capacity. About one-sixth of the world’s cropland would be needed. • Stop all deforestation. • Expand conservation tillage to all cropland (normal plowing releases carbon by speeding decomposition of organic matter). 41
• Reject • Reduce • Recycle • Reconstruct 42
• STOP AC STOP CFC • Use Public Transport • Minimize use of Cars. Don’t Burn Unnecessary Fuel • Use CFL Light • Use Capacitors For Agro-Pumps • Avoid Pesticides • Avoid excess use of Water • STOP BURNING FORESTS 43
• Stop TV , Computers , Microwave ovens At Mains when Not In Use • Increase Use of Bicycles • Plantation of New Trees of Different Nature. Avoid Monoculture. • Form a Village Group For Action Plan 44
Conclusions : • Climate change is a reality. • Indian agriculture is likely to suffer losses in long run due to heat, erratic weather, and decreased irrigation availability. • Adaptation strategies can help minimize negative impacts to some extent. • These need research and policy support. 45
Thank you Department of Environmental Science, Shivaji University, Kolhapur 46
Скачать презентацию Climate Change Agriculture and Sustainable Development Dr S
5139b2ecca6d5893d3f45bf3860d360f.ppt