Climate Change Impacts on Agriculture Weather and the related temperature, light and water determine to a large extent the human society's ability to feed themselves and the animals they care for. When the weather changes due to variations n climate or long-terms changes in climate there are very serious impacts on agricultural production and reduction of crop production and these force the farmers to take up new methods of agriculture so that they can cope up with the new situation. Food security of the world is thus directly affected by the existing climate. (Agriculture and climate change: FAO's role) The changes in climate directly affects climate due to both its effect on the agricultural processes and the impact of the changes of climate on agricultural production. One does not really know totally how all this takes place and how the agricultural processes can be altered so that the impact can be minimized on agricultural production. Human civilization has been depending on agriculture right from the inception and has always been one of the fundamental methods by which humans have been surviving in the world. (Agriculture and Global Environmental Change)

The methods and the production from agriculture is still the main contributor to economy in the developing countries. In certain cases, even the agricultural processes may be contributing to the changes in climate through arable farming, burning and clearing of forests, cultivation of rice in wetlands, raising livestock, use of nitrogenous fertilizers and the resultant increase of carbon dioxide in the atmosphere, the development of methane and nitrous oxide in the air, and so on. At the same time, when the changes in global climate take place, it reduces the availability of land for cultivation, decreases the yield of crops and thus threatens food security. This affects the developing countries a lot. (Agriculture and Global Environmental Change)

Most of these threats are being ignored: climate change, erosion of soil, depletion of water aquifers and expansion of deserts. These changes are all threatening the livelihood and food availability of hundreds of millions of people all over the world. Many of the present national governments do not even recognize these problems. (Time for plan B) It is thus important to note down and inform people of the world about the changes being caused to agriculture due to climate changes, and the changes in climate due to agricultural processes. It is important to apply the correct technology and government policies to reduce these changes in climate. The importance is for the nations, regions and local areas. Normally the people in the local area are aware of the environment in which they live, and these technologies and policies can come out of the human ability to adapt. (Agriculture and Global Environmental Change)

Growth in population and increase of income has tripled the demand for grains in the world during the last fifty years and the growth has been from 640 million tons in 1950 to 1855 million tons in 2000. The point now has to be recognized as to whether the farming community can increase production by 100 million tons a year, so that the 70 million people being added to the world a year can be fed, and along with that build up the stocks in the world to a secure level. The main challenges to the farmers are the rising temperatures and falling ground water levels. The temperatures in the world have risen sharply since agriculture was started by man 11,000 years ago. Along with this, the farmers are now the water in the aquifer they use disappear and a resultant loss of irrigation water. During the last thirty years, the temperatures have been rising steadily. (Time for plan B)

The process of recording temperatures began from 1880, and the 16 hottest years have been after 1980. The hottest three years have come in the last five years and the crops are facing a lot of high temperatures that they have not...

This reduces crop yields through the impact on photosynthesis, moisture balance and fertilization. It has been seen that the process of photosynthesis slows down when the temperatures cross 94 degrees Fahrenheit, and many crops are not able to photosynthesize above temperatures over 100 degrees. So far as the United States is concerned, the corn plants get into thermal shock and dehydrate when the temperatures in the corn belt go over 100 degrees. At those temperatures, every additional day reduces the harvest. The high temperatures also reduce the fertilization needed for the development of seeds. (Time for plan B)
The thumb rule accepted by the research scientists at the United States Department of Agriculture and the International Rice Research Institute in the Philippines is that an increase in temperature by one degree Celsius, over the optimum and during the growing season, will reduce the yield of grain by 10%. The other challenge to the farmers is the rapidly falling water levels. Earlier, the lifting of water from the underground sources used to be done by devices where the motive power used to be provided by men or animals, and these could not provide enough power to draw down their levels. During the last fifty years or so, the drawing of water is done through diesel and electric pumps and these are leading to using of too much water. This has led to a steady increase in the demand for water, including the three countries of China, India and United States which supply fifty percent of the world' grain. In addition to these countries, the water levels are also falling in other countries. This is leading to a situation where the cutbacks in grain production are inevitable, and almost at about the same time. This is being combined with a high growth in population of 70 million a year. (Time for plan B)

It is almost impossible to predict when the growth in food production will drop below the increase in demand due to the growth of population and that will certainly drive up prices. This will lead to a situation when food will become an issue of national security, and this is told by the slowdown of growth in harvest, dropping water levels, and increasing temperatures. The last time grain prices started rising was in 1972-74, and then there was immediately the start of a politics of food scarcity. The countries which were then exporting grain started restricting exports so that the price of grain within the country did not rise. The poorest people in the world now spend 70% of their income on their food grains, and when this rises, it would be a real threat to their existence. If the food prices in the world were to double in a short time, these people would be impoverished almost immediately. They would then naturally blame their governments, and the governments of these low-income, grain-importing countries are likely to be affected. (Time for plan B)

There as always been a natural variation in rainfall, temperature and related conditions in certain parts of the world leading to food insecurity due to variation of agricultural production. This is clearly observed in certain parts of the world like the Sahel, northeast Brazil, central Asia and Mexico - more than other parts of the world. There are also extremes of climate through unusual effects like floods, drought, and storms, which have a high visual impact. The second type of effects has far lesser impact on agricultural production than the first type. The variations in climate and increases of extreme climate may both occur due to the prevalent global warming. (Agriculture and climate change: FAO's role) These changes in climate for a large number of years could effect agricultural production in many ways, and they would all increase food insecurity for the most vulnerable people in the world. It would become impossible to predict the coming weather and climate, and that would make planning for agriculture more difficult. (Agriculture and climate change: FAO's role)

The variations in climate will increase, and that would lead to greater difficulties in farming of difficult terrain. The extremes in climate will increase and it would be impossible to provide for them. The agricultural lands near the coasts would be submerged by the rising sea, as also the nearby low islands. The mangroves and tropical forests would be submerged leading to a loss of substantial amount of fragile environments. The geographical positions of suitable climates for agriculture would shift, and this would lead to a lot of changes and threaten natural vegetation and fauna. The existing imbalance between the food production in the cool and temperate regions and the tropical and subtropical regions would be even more pronounced. In addition to the direct impact on agriculture, the situation regarding fish and seafood also will change and this will damage the existing activities in fishing. The changes in climate will send pests and vector borne diseases into areas that they were not known before. (Agriculture and climate change: FAO's role)

There will be an initial automatic series of responses to climate…