As global warming causes climate change, the issue of effects of global warming on agriculture due to the change in weather conditions is often invoked in arguments on the course of action involving prediction of climate events. These conditions, including temperature, radiation and water, determine the carrying capacity of the biosphere to produce enough food for the human propulation and domesticated animals. Any short-term fluctuations of the climate can have dramatic effects on the agricultural productivity. Thus, the climate has a direct incidence on food supply. Also, the often thought anthropogenic cause of global warming, an increase in the amount of carbon dioxide levels, would also have effects, both detrimental and beneficial, on crop yields. Global mean surface temperatures 1856 to 2004 Mean temperature anomalies during the period 1995 to 2004 with respect to the average temperatures from 1940 to 1980 Global warming describes an increase in the average temperature of the Earths atmosphere and oceans. ... Variations in CO2, temperature and dust from the Vostok ice core over the last 400 000 years The term climate change is used to refer to changes in the Earths global climate or regional climates. ... Composite satellite image showing the progress of a hurricane weather system approaching the East Coast of the United States Weather comprises all the various phenomena that occur in the atmosphere of a planet. ... Temperature is the physical property of a system which underlies the common notions of hot and cold; the material with the higher temperature is said to be hotter. ... Radiation has a variety of different meanings. ... Water (from the Old English word wæter; c. ... In ecology, carrying capacity is the measure of an environment, or habitat, to indefinitely sustain the population of a particular species in a steady-state population density. ... The biosphere is that part of a planets outer shell—including air, land, surface rocks and water—within which life occurs, and which biotic processes in turn alter or transform. ... Food distribution is a vital factor in public nutrition. ... Anthropogenic effects or processes are derived from human activities, as opposed to effects or processes that occur in the natural environment without human influences. ... Carbon dioxide is an atmospheric gas comprised of one carbon and two oxygen atoms. ...

It is hoped that a positive effect of global warming would be increased agricultural yields, because of the role of carbon dioxide in photosynthesis. Global mean surface temperatures 1856 to 2004 Mean temperature anomalies during the period 1995 to 2004 with respect to the average temperatures from 1940 to 1980 Global warming describes an increase in the average temperature of the Earths atmosphere and oceans. ...

Assessment of the effects of global climate changes on agriculture might help to properly anticipate and adapt farming to maximize agricultural production. A farmer in Germany working the land in the traditional way, with a horse and plough Agriculture is the process of producing food, feed, fiber and other desired products by the cultivation of certain plants and the raising of domesticated animals (livestock). ...

Background

Assessment: global vs local

Despite technological advances, such as improved varieties, genetically modified organisms, and irrigation systems, weather is still a key factor in agricultural productivity, as well as soil properties and natural communities. The effect of climate on agriculture is related to variabilities in local climates rather than in global climate patterns. Consequently, agronomists consider any assessment has to be individually consider each local area. ... Italic textGMO is a three-letter abbreviation that could mean: genetically modified organism Gulf, Mobile and Ohio Railroad (AAR reporting mark GMO) This page concerning a three-letter acronym or abbreviation is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ... High-altitude aerial view of irrigation in the Heart of the Sahara Irrigation (in agriculture) is the replacement or supplementation of rainfall with water from another source in order to grow crops. ... Composite satellite image showing the progress of a hurricane weather system approaching the East Coast of the United States Weather comprises all the various phenomena that occur in the atmosphere of a planet. ... Soil is unconsolidated rock particles mixed with organic matter from plant decay. ... Biota can refer to several things: The plant and animal life of a region; see biota (ecology) A municipality in Zaragoza, Aragon, Spain; see Biota (municipality) A superdomain in taxonomy; see Biota (taxonomy) Biota Holdings, the Australian biotech company This is a disambiguation page — a navigational aid which lists other... Agricultural science (also called agronomy) is a broad multidisciplinary field that encompasses the parts of exact, natural, economic, and social sciences that are used in the practice and understanding of agriculture. ... An ecoregion is a relatively large area of land or water that contains a geographically distinct assemblage of natural communities. ...

On the other hand, agricultural trade has grown in the recents years, and now provides significant amounts of food, on a national level to major importing countries, as well as comfortable income to exporting ones. The international aspect of trade and security in terms of food implies the need to also consider the effects of climate change on a global scale. Agricultural economics applies the principles of economics to the production of crops and livestock. ... In economics, gross domestic product (GDP) is a measure of the value of economic production of a particular territory in financial capital terms during a specified period. ... The term climate change is used to refer to changes in the Earths climate. ...

IPCC

The 2001 IPCC Third Assessment Report concluded that the poorest countries would be hardest hit, with reductions in crop yields in most tropical and sub-tropical regions due to decreased water availability, and new or changed insect pest incidence. In Africa and Latin America many rainfed crops are near their maximum temperature tolerance, so that yields are likely to fall sharply for even small climate changes; falls in agricultural productivity of up to 30% over the 21st century are projected. Marine life and the fishing industry will also be severely affected in some places. IPCC is science authority for the UNFCCC The Intergovernmental Panel on Climate Change (IPCC) was established in 1988 by two United Nations organizations, the World Meteorological Organization (WMO) and the United Nations Environment Programme (UNEP) to assess the risk of human-induced climate change. The Panel is open to all... The Third Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) was issued in 2001. ...

Shortage in grain production

Between 1996 and 2003, grain production has stabilized slightly over 1800 millions of tons. In 2000, 2001, 2002 and 2003, grain stocks have been dropping, resulting in a global grain harvest that was short of consumption by 93 millions of tons in 2003. 1996 (MCMXCVI) is a leap year starting on Monday of the Gregorian calendar, and was designated the International Year for the Eradication of Poverty. ... 2003 (MMIII) is a common year starting on Wednesday of the Gregorian calendar. ... Cereal crops are mostly grasses cultivated for their edible seeds (actually a fruit called a caryopsis). ... The word ton or tonne is derived from the Old English tunne, and ultimately from the Old French tonne, and referred originally to a large cask with a capacity of 252 wine gallons, which holds approximately 2100 pounds of water. ... This article is about the year 2000. ... 2001: A Space Odyssey. ... 2002 (MMII) is a common year starting on Tuesday of the Gregorian calendar. ... Hay bales after harvest in Schleswig-Holstein, Germany In agriculture, harvesting is the process of gathering mature crops from the fields. ... Consumption is the using up of a resource. ...

The earth's average temperature has been rising since the late 1970s, with the three warmest years on record coming in the last five years. In 2002, India and the United States suffered sharp harvest reductions because of record temperatures and drought. In 2003 Europe suffered very low rainfall throughout spring and summer, and a record level of heat damaged most crops from the United Kingdom and France in the Western Europe through Ukraine in the East. Bread prices have been rising in several countries in the region. (see w:fr:canicule 2003). The 1970s in its most obvious sense refers to the decade between 1970 and 1979. ... A drought is an extended period where water availability falls below the statistical requirements for a region. ... A satellite composite image of Europe Europe is the worlds second-smallest continent in terms of area, with an area of 10,600,000 km² (4,140,625 square miles), making it larger than Australia only. ... In meteorology, precipitation is any kind of water that falls from the sky as part of the weather. ... Spring is one of the four seasons of temperate zones. ... Summer is a season, defined by convention in meteorology as the whole months of June, July, and August, in the Northern hemisphere, and the whole months of December, January, and February, in the Southern hemisphere. ... A farmer in Germany working the land in the traditional way, with a horse and plough Agriculture is the process of producing food, feed, fiber and other desired products by the cultivation of certain plants and the raising of domesticated animals (livestock). ... Western Europe is distinguished from Eastern Europe by differences of history and culture rather than by geography. ... Pre-1989 division between the West (grey) and Eastern Bloc (orange) superimposed on current national boundaries: Russia (dark orange), other countries of the former USSR (medium orange) and other former communist regimes (light orange). ... French bread has a somewhat rigid crust. ... In economics and business, the price is the assigned numerical monetary value of a good, service or asset. ...

Increases in agricultural production

Between [2003] and [2004] worldwide wheat production increased 13%, oilseed production increased 16%, rice production increased 3%, and cotton production increased 23%. [1]

Models and scenarios used to estimate global climate change consequences

Some major limitations to climate changes consequences estimates are related to the models that are being used. The climate models do not have a true ability to give accurate projections because of inadequate understanding of natural processes and the limitation of computing power, and the sheer amount of variables which bring in the need to invoke chaos theory. As a consequence, the assessment of possible effects of climate changes are based on estimations. Most models are also not able yet to provide reliable projections of changes in climate variability on a local scale, or in frequency of exceptional events such as storms and drought. For example, there tends to be a lack of consensus among experts in prediction of regional soil moisture changes. Climate models use quantitative methods to simulate the interactions of the atmosphere, oceans, land surface, and ice. ... In computer science and mathematics, a variable is a symbol denoting a quantity or symbolic representation. ... In mathematics and physics, chaos theory deals with the behavior of certain nonlinear dynamical systems that (under certain conditions) exhibit the phenomenon known as chaos, most famously characterised by sensitivity to initial conditions (see butterfly effect). ... Extreme weather is weather phenomena indicative of an unstable climate; that is, weather that is at the extremes of historical patterns, especially severe or unseasonal weather. ... Consensus has two common meanings. ... Soil is unconsolidated rock particles mixed with organic matter from plant decay. ... Moisture generally refers to the presence of water in trace amounts. ...

Crop development models

In order to further study effects of global warming on agriculture, other types of models, such as crop development models, yield prediction, quantities of water or fertilizer consumed, can be used. Such models condense the knowledge accumulated of the climate, soil, and effects observed of the results of various agricultural practices. They thus could make it possible to test strategies of adaptation to modifications of the environment. Farming, ploughing rice paddy, in Indonesia Agriculture is the process of producing food, feed, fiber and other desired products by the cultivation of certain plants and the raising of domesticated animals (livestock). ...

Because these models are necessarily simplifying natural conditions (often based on the assumption that weeds, disease and insect pests are controlled), it is not clear whether the results they give will have an in-field reality. However, some results are partly validated with an increasing number of experimental results. Dandelions, shown here in proliferation, are commonly thought of as weeds. ... A disease is any abnormal condition of the body or mind that causes discomfort, dysfunction, or distress to the person affected or those in contact with the person. ... Look up Pest in Wiktionary, the free dictionary Pest may refer to: A pest, an animal (usually an insect), or sometimes a plant (weed) with characteristics that are injurious or harmful to humans. ...

Other types of biological models

Other models, such as insect and disease development models based on climate projections are also used (for example simulation of aphid reproduction or septoria (cereal fungal disease) development). Families There are 10 families: Adelgidae - adelgids, conifer aphids Anoeciidae Aphididae Drepanosiphidae Greenideidae Hormaphididae Lachnidae Mindaridae Pemphigidae Phloeomyzidae Phylloxeridae Thelaxidae Aphids or aphides, also known as blight, greenfly, plant lice (superfamily Aphidoidea) are minute plant-feeding insects (1 to 10 mm). ... Septoria is a fungal disease due to Septoria tritici. ...

Scenarios are used in order to estimate climate changes effects on crop development and yield. Each scenario is defined as a set of meteorological variables, based on generally accepted projections. For example, many models are running simulations based on doubled carbon dioxide projections, temperatures raise ranging from 1°C up to 5°C, and with rainfall levels an increase or decrease of 20%. Other parameters may include humidity, wind, and solar activity. Scenarios of crop models are testing farm-level adaptation, such as sowing date shift, climate adapted species (vernalisation need, heat and cold resistance), irrigation and fertilizer adaptation, resistance to disease. Most developed models are about wheat, maize, rice and soybean. Development has meaning in several contexts: Science and Engineering Biological development of embryos in the context of developmental biology Child development or post-natal human development (pediatrics, etc) Software engineering, the methodology and process of development of computer software Technology development in industry, as in Software development New product development... Meteorology is the scientific study of the atmosphere that focuses on weather processes and forecasting. ... Carbon dioxide is an atmospheric gas comprised of one carbon and two oxygen atoms. ... Temperature is the physical property of a system which underlies the common notions of hot and cold; the material with the higher temperature is said to be hotter. ... The degree Celsius (°C or ℃ (Unicode 0x2103)) is a unit of temperature named after the Swedish astronomer Anders Celsius (1701–1744), who first proposed a similar system in 1742. ... In meteorology, precipitation is any kind of water that falls from the sky as part of the weather. ... This article needs to be cleaned up to conform to a higher standard of quality. ... Wind is the quasi-horizontal movement of air (as opposed to an air current) caused by Howard Sterns asshole. ... 20 years of solar irradiance data from satellites Solar variation refers to fluctuation in the amount of energy emitted by the Sun. ... Vernalization is a requirement of some temperate cereal crops and trees for a period of low winter temperature to initiate or accelerate the flowering process. ... High-altitude aerial view of irrigation in the Heart of the Sahara Irrigation (in agriculture) is the replacement or supplementation of rainfall with water from another source in order to grow crops. ... Species T. boeoticum T. durum T. monococcum T. spelta References:   ITIS 42236 2002-09-22 Wheat (Triticum spp. ... Binomial name Zea mays L. Maize (Zea mays ssp. ... Binomial name Oryza sativa L. Rice (Oryza sativa) is a species of grass in the genus Oryza, native to tropical and subtropical southeastern Asia, where it grows in wetlands. ... Binomial name Glycine max Merr. ...

Consequences of potential global climate changes on agricultural production

Many scientists hold the position that agricultural shifts are likely. The possible effects proposed are listed below:

The first direct effect is the composition of the earth atmosphere, such the amount of carbon dioxide and ozone. Gases such as methane, nitrogen dioxide and chloroflourocarbon however, are commonly believed not to have any effect on physiological processes. Some indirect effects are climate parameters resulting from climate change, such as temperature, insolation, rainfall, and humidity. Other indirect effects include the side effects due to the climatic changes, such as the increase of the sea level, changes in ocean currents, or tornadoes. Ozone (O3) is an allotrope of oxygen, the molecule consisting of three oxygen atoms instead of the more stable diatomic O2. ... R-phrases S-phrases , , , Flash point −188 °C Autoignition temperature 537 °C Explosive limits 5–15% Supplementary data page Structure and properties n, εr, etc. ... The chemical compound nitrogen dioxide (NO2) is a red or orange/brown gas with a characteristic sharp, biting odor. ... The haloalkanes are a group of chemical compounds, consisting of alkanes, such as methane or ethane, with one or more halogens linked, such as chlorine or fluorine. ... Insolation is the incoming solar radiation that reaches a planet and its atmosphere. ... For considerations of sea level change, in particular rise associated with possible global warming, see sea level rise. ... For the album by Ocean Colour Scene, see North Atlantic Drift (album) The Gulf Stream is orange and yellow in this representation of water temperatures of the Atlantic. ... A tornado. ...

All these influences may combine negatively or positively - the assessment of these effects depends on whether one considers annuals crops (cereals and legumes) or herbaceous perennial cultures (fodder, meadows) or other cultures such as vine or fruit trees. The effects are also different depending on the latitude. In temperate countries, effects are found less negative or even rather beneficial, while in tropical and desertic countries they tend to be adverse. Effects also depend on altitude, for example, places at higher altitudes tend to benefit from a warmer temperature. A farmer in Germany working the land in the traditional way, with a horse and plough Agriculture is the process of producing food, feed, fiber and other desired products by the cultivation of certain plants and the raising of domesticated animals (livestock). ... Cereal crops are mostly grasses cultivated for their edible seeds (actually a fruit called a grain, technically a caryopsis). ... Varieties of soybean seeds, a popular legume The term legume has two closely related meanings in botany, a situation encountered with many botanical common names of useful plants whereby an applied name can refer to either the plant itself, or to the edible fruit (or useful part). ... This article is about the plants used in cooking and medicine. ... A Red Valerian, a perennial plant. ... In biology, a culture refers to a growth of bacteria or other microorganisms which is grown in a laboratory. ... In agriculture, fodder or animal feed is any foodstuff that is used specifically to feed livestock, such as cattle, sheep, chickens and pigs. ... A meadow is a tract of grassland, either in its natural state or used as pasture or for growing hay. ... Latitude, sometimes denoted by the Greek letter φ, gives the location of a place on Earth north or south of the Equator. ... In geography, temperate latitudes of the globe lie between the tropics and the polar circles. ... The tropics are the geographic region of the Earth centered on the equator and limited in latitude by the two tropics: the Tropic of Cancer in the north and the Tropic of Capricorn in the southern hemisphere. ... A dune in the Egyptian desert Desert in California In geography, a desert is a landscape form or region that receives little precipitation - less than 250 mm per year. ...

Climate change induced by increasing greenhouse gases is likely to affect crops differently from region to region. For example, average crop yield is expected to drop down to 50% in Pakistan according to the UKMO scenario whereas corn production in Europe is expected to grow up to 25% in optimum hydric conditions. Increasing atmospheric CO2 levels as measured at Mauna Loa. ... The new building on the edge of Exeter The Met Office (originally an abbreviation for Meteorological Office, but now the official name in itself), which has its headquarters at Exeter in Devon, is the UKs national weather service. ... This page is a candidate to be moved to Wiktionary. ...

More favourable effects on yield tend to depend to a large extent on realization of the potentially beneficial effects of carbon dioxide on crop growth and increase of efficiency in water use. Decrease in potential yields is likely to be caused by shortening of the growing period, decrease in water availability and poor vernalization.

Temperature potential effect on growing period

Duration of crop growth cycles are above all, related to temperature. An increase in temperature will speed up development. In the case of an annual crop, the duration between sowing and harvesting will shorten (for example, the duration in order to harvest corn could shorten between one and four weeks). The shortening of such a cycle would have an adverse effect on productivity because senescence would occur sooner. Temperature changes could also have serious implications for crops and trees that need vernalisation. growth is the physical increase in size. ... A cycle (Latin cyclus, from Greek kuklos meaning circle) is anything round, in the physical sense (e. ... Sowing is the process of planting seeds. ... This article is about gathering crops. ... In biology, senescence is the state or process of aging which follows the period of development. ... Vernalization is a requirement of some temperate cereal crops and trees for a period of low winter temperature to initiate or accelerate the flowering process. ...

Potential effect of atmospheric carbon dioxide on yield

Carbon dioxide could have both positive and negative consequences. Carbon dioxide is an atmospheric gas composed of one carbon and two oxygen atoms. ...

CO2 is expected to have positive physiological effects by increasing the rate of photosynthesis. Currently, the amount of carbon dioxide in the atmosphere is 380 parts per million. In comparison the amount of oxygen, is very much higher, at 21,000. This means that often plants may be starved of carbon dioxide, being outnumbered by the photosynthetic pollutant oxygen. The effects of an increase in carbon dioxide would be higher on C3 crops (such as wheat) than on C4 crops (such as maize), because the former is more suspectible to carbon dioxide shortage. Under optimum conditions of temperature and humidity, the yield increase could reach 36%, if the levels of carbon dioxide are doubled. Leaf. ... Parts per million (ppm) is a measure of concentration that is used where low levels of concentration are significant. ... General Name, Symbol, Number oxygen, O, 8 Chemical series nonmetals Group, Period, Block 16, 2, p Appearance colorless Atomic mass 15. ... C3 carbon fixation is a pathway for carbon fixation in photosynthesis. ... Species T. boeoticum T. durum T. monococcum T. spelta References:   ITIS 42236 2002-09-22 Wheat (Triticum spp. ... For other meanings of C4, see C4 (disambiguation) C4 carbon fixation is a common metabolic pathway found in land [[plant](C4 plants). ... Binomial name Zea mays L. Maize (Zea mays ssp. ...

A higher level of carbon dioxide would also allow plants to close their stomata, or make the opening smaller, reducing the loss of water through transpiration. This is because higher carbon dioxide levels would allow the stomata to be closed without suffering photorespiration, which due to too much oxygen in ratio to carbon dioxide, in the plant cell's chloroplasts. Due to the carbon dioxide starvation mentioned above, the carbon dioxide molecules are outnumbered by oxygen molecules, oxygen often replaces carbon dioxide in the Calvin Cycle first. This not only halts sugar production but destroys existing sugars, badly stunting growth and crop output. Higher levels of carbon dioxide would reduce this likelihood, allowing sugar production to take place without destructive setbacks due to oxygen. This would mean the plant would be able to be able to allow the waste product of photosynthesis, oxygen to remain longer inside the chloroplasts, which would normally exit through the stomata, which is the normal solution to excess carbon dioxide. Allowing the stomata to be closed, and thus the reduction of loss of water decreases the plants need for water. This is not about surgically created bowel openings; see stoma (medicine) In botany, a stoma (also stomate; plural stomata) is a tiny opening or pore, found mostly on the undersurface of a plant leaf, and used for gas exchange. ... Evapotranspiration (ET) is the sum of evaporation and plant transpiration. ... Photorespiration is an alternate pathway for Rubisco, the main enzyme of photosynthesis (specifically, the Calvin cycle). ... Plant cell structure // Overview The cells of plants are quite different from the cells of the other eukaryotic kingdoms organisms. ... The inside of a chloroplast The inside of a chloroplast Chloroplasts are organelles found in plant cells and eukaryotic algae which conduct photosynthesis. ... Overview of the Calvin cycle and carbon fixation The Calvin cycle (or Calvin-Benson cycle) is a series of biochemical reactions that takes place in the chloroplasts of photosynthetic organisms. ... In general use, sugar is taken to mean sucrose, also called table sugar or saccharose, a disaccharide which is a white crystalline solid. ...

However, other studies also show a change in harvest quality. The growth improvement in C3 plants could favor vegetative biomass on grain biomass; thus leading to a decrease in grain production yield. C3 carbon fixation is a pathway for carbon fixation in photosynthesis. ... Biomass is organic non-fossil material, collectively. ...

Carbon dioxide is believed by many scientists to be potentially responsible of increase in agricultural production: a 10-15 % increase for wheat and soybean, 8% for corn and rice for a +2°C scenario on average. However, these results mask great differences among countries.

Effect on quality

According to the IPCC's TAR, "The importance of climate change impacts on grain and forage quality emerges from new research. For rice, the amylose content of the grain--a major determinant of cooking quality--is increased under elevated CO2 (Conroy et al., 1994). Cooked rice grain from plants grown in high-CO2 environments would be firmer than that from today's plants. However, concentrations of iron and zinc, which are important for human nutrition, would be lower (Seneweera and Conroy, 1997). Moreover, the protein content of the grain decreases under combined increases of temperature and CO2 (Ziska et al., 1997)."[2]

More than 100 studies have shown that higher CO2 levels lead to reduced plant uptake of nitrogen (and a smaller number showing the same for trace elements such as zinc) resulting in crops with lower nutritional value.[3] [4] This would primarily impact on populations in poorer countries less able to compensate by eating more food, more varied diets, or possibly taking supplements.

Reduced nitrogen content in grazing plants has also been shown to reduce animal productivity in sheep, which depend on microbes in their gut to digest plants, which in turn depend on nitrogen intake.[5]

Global warming and water distribution

Global warming would be able to modify the global distribution of water, possibly leading to several effects, both detrimental and beneficial.

Effects of water availability on productivity

Water is one of the major limiting factors in the growth and production of crops worldwide. In spite of better water efficiency use, higher summer temperature and lower summer rainfall caused by global warming is likely to have adverse effects. The intensification of the extremes of the hydrological global cycle, will have consequences such as more frequent drought in northern sub-tropical areas or desertification extension in arid areas, while causing devastating flood in other areas. The water cycle—technically known as the hydrologic cycle—is the circulation of water within the earths hydrosphere, involving changes in the physical state of water between liquid, solid, and gas phases. ... A drought is an extended period where water availability falls below the statistical requirements for a region. ... Ship stranded by the retreat of the Aral Sea Desertification is the degradation of land in arid, semi arid and dry sub-humid areas into desert, resulting from various factors including climatic variations and human activities. ... Look up Flood on Wiktionary, the free dictionary A flood (in Old English flod, a word common to Teutonic languages; compare German Flut, Dutch vloed from the same root as is seen in flow, float) is an overflow of water, an expanse of water submerging land, a deluge. ...

In developed areas of the world agriculture, and competing industry and municipal users mine fossil water supplies. In coastal areas, deep water wells also reverse normal ground water flow toward the ocean, leading to saline water intrusion into aquifers. Further increases in usage would force societies to conform ground water usage to actual recharge rates. A fossil Ammonite Fossils are the mineralized remains of animals or plants or other traces such as footprints. ... Run-off or runoff may refer to one of the following. ... Saltwater intrusion is a natural process that occurs in virtually all coastal aquifers. ... An aquifer is an underground layer of water-bearing permeable rock, or permeable mixtures of unconsolidated materials (gravel, sand, silt, or clay) (see also groundwater). ...

Temporal variability and forecasting of the climate

If global warming happens, many believe the general ability to predict weather patterns will decrease, due to more extreme weather. This would make it more difficult to plan agricultural actions. If extreme climatic conditions become more frequent, there would be more intense rainfall, droughts and heat spells in different parts of the globe or the year.

Agricultural surfaces and climate changes

Climate change is likely to increase the amount of arable land near the poles by reduction of the amount of frozen lands. Sea levels are expected to get up to one meter higher by 2100, though this projection is disputed. Rise in sea level would result in agricultural land loss, in particular in areas such as South East Asia. Erosion, submergence of shorelines, salinity of the water table due to the increased sea levels, could mainly affect agriculture through inundation of low-lying lands. In geography, arable land (from Latin arare, to plough ) is a form of agricultural land use, meaning land that can be (and is) used for growing crops. ... For considerations of sea level change, in particular rise associated with possible global warming, see sea level rise. ... 2100 is the last year of the 21st century. ... Location of Southeast Asia Southeast Asia is a subregion of Asia. ... Severe soil erosion in a wheat field near Washington State University, USA. Erosion is the displacement of solids (soil, mud, rock, and so forth) by the agents of wind, water, ice, movement in response to gravity, or living organisms (in the case of bioerosion). ... Measurement of recent sea level rise from 23 long tide gauge records in geologically stable environments Changes in sea level since the end of the last glacial episode Sea level rise is an increase in sea level. ... Salinity is the saltiness or dissolved salt content of a body of water. ... The water table is the upper limit of abundant groundwater. ... A flood (in Old English flod, a word common to Teutonic languages; compare German Flut, Dutch vloed from the same root as is seen in flow, float) is an overflow of water, an expanse of water submerging land, a deluge. ... This article needs to be wikified. ...

Erosion and fertility

With global warming, soil degradation is more likely to occur, and soil fertility would probably be affected by global warming. However, due to the fact that the ratio]] of carbon to nitrogen is a constant, a doubling of carbon is likely to imply a higher storage of nitrogen in soils as nitrates, thus providing higher fertilizing elements for plants, providing better yields. The average needs for nitrogen could decrease, and give the opportunity of changing often costly fertilisation strategies. Retrogression and degradation are two regressive evolution processes associated with the loss of equilibrium of a stable soil. ... Fertility is the ability of people or animals to produce healthy offspring in abundance. ... In mathematics and the mathematical sciences, a constant is a fixed, but possibly unspecified, value. ... General Name, Symbol, Number nitrogen, N, 7 Chemical series nonmetals Group, Period, Block 15, 2, p Appearance colorless Atomic mass 14. ... this is a negative ion,NO3- Discussion In inorganic chemistry, nitrates are the salts of nitric acid. ... A spermatozoon fertilising an ovum Fertilisation (also known as conception, fecundation and syngamy) is fusion of gametes to form a new organism. ...

Due to the extremes of climate that would result, the increase in precipitations would probably result in greater risks of erosion, according to the intensity of the rain. The possible evolution of the organic matter in the soil is a highly contested issue: while the increase in the temperature would induce a greater rate in the production of minerals, lessening the soil organic matter content, the atmospheric CO2 concentration would tend to increase it. Severe soil erosion in a wheat field near Washington State University, USA. Erosion is the displacement of solids (soil, mud, rock, and so forth) by the agents of wind, water, ice, movement in response to gravity, or living organisms (in the case of bioerosion). ... Rain falling For other uses see Rain (disambiguation). ... Organic has several meanings and related topics. ... Minerals are natural compounds formed through geological processes. ...

Potential effects of global climate change on pests, diseases and weeds

A very important point to consider is that weeds would undergo the same acceleration of cycle as cultivated crops, and would also benefit from carbonaceous fertilization. Since most weeds are C3 plants, they are likely to compete even more than now against C4 crops such as corn. However, on the other hand, some results make it possible to think that weedkillers could gain in effectiveness with the temperature increase. Dandelions, shown here in proliferation, are commonly thought of as weeds. ... A herbicide is a pesticide used to kill unwanted plants. ...

Global warming would cause an increase in rainfall in some areas, which would lead to an increase of atmospheric humidity and the duration of the wet seasons. Combined with higher temperatures, these could favor the development of fungal diseases. Similarly, because of higher temperatures and humidity, there could be an increased pressure from insects and disease vectors. The wet season and the rainy season are terms used to describe seasons in which the average rainfall in a region is significantly increased. ... Divisions Chytridiomycota Zygomycota Ascomycota Basidiomycota The Fungi (singular: fungus) are a large group of organisms ranked as a kingdom within the Domain Eukaryota. ... Classes & Orders Subclass: Apterygota Orders Archaeognatha (Bristletails) Thysanura (Silverfish) Monura - extinct Subclass: Pterygota Infraclass: Paleoptera (paraphyletic) Orders Ephemeroptera (mayflies) Protodonata - extinct Odonata (dragonflies and damselflies) Diaphanopteroidea - extinct Palaeodictyoptera - extinct Megasecoptera - extinct Archodonata - extinct Infraclass: Neoptera Orders Blattodea (cockroaches) Isoptera (termites) Mantodea (mantids) Dermaptera (earwigs) Plecoptera (stoneflies) Protorthoptera - extinct Orthoptera (grasshoppers... Traditionally in medicine, a vector is an organism that does not cause disease itself but which spreads infection by conveying pathogens from one host to another. ...

Ozone and UV-B

Some scientists think agriculture could be affected by any decrease in stratospheric ozone, which could increase biologically dangerous ultraviolet radiation B. Excess ultraviolet radiation B can directly effect plant physiology and cause massive amounts of [[mutation]s, and indirectly through changed pollinator behavior, though such changes are difficult to quantify. [6] However, it has not yet been ascertained whether an increase in greenhouse gases would decrease stratospheric ozone levels. Ozone (O3) is an allotrope of oxygen, the molecule consisting of three oxygen atoms instead of the more stable diatomic O2. ... Ultraviolet (UV) radiation is electromagnetic radiation of a wavelength shorter than that of the visible region, but longer than that of soft X-rays. ... Physiology (in Greek physis = nature and logos = word) is the study of the mechanical, physical, and biochemical functions of living organisms. ... A pollinator is the agent that moves pollen from the male anthers of a flower to the female stigma of a flower to accomplish fertilization or syngamy of the female gamete in the ovule of the flower by the male gamete from the pollen grain. ...

In addition, a possible effect of rising temperatures is significantly higher levels of ground-level ozone, which would substantially lower yields.[7]

Conclusions

In the long run, the climatic change could affect agriculture in several ways :

• productivity, in terms of quantity and quality of crops
• agricultural practices, through changes of water use (irrigation) and agricultural inputs such as herbicides, insecticides and fertilizers
• environmental effects, in particular in relation of frequency and intensity of soil drainage (leading to nitrogen leaching), soil erosion, reduction of crop diversity
• rural space, through the loss of previously cultivated lands, land speculation, land renunciation, and hydraulic amenities.

They are large uncertainties to uncover, particularly because there is lack of information on many specific local regions, and include the uncertainties on magnitude of climate change, the effects of technological changes on productivity, global food demands, and the numerous possibilities of adaptation. Quantity is a generic term used when referring to the measurement (count, amount) of a scalar, vector, number of items or to some other way of denominating the value of a collection or group of items. ... Quality refers to the inherent or distinctive characteristics or properties of a person, object, process or other thing. ... Image:Http://www. ... An insecticide is a pesticide whose purpose is to kill or to prevent the multiplication of insects. ... Fertilizers or fertilisers are compounds given to plants with the intention of promoting growth; they are usually applied either via the soil, for uptake by plant roots, or by foliar spraying, for uptake through leaves. ... Drainage is the natural or artificial removal of surface and sub-surface water from a given area. ... Severe soil erosion in a wheat field near Washington State University, USA. Erosion is the displacement of solids (soil, mud, rock, and so forth) by the agents of wind, water, ice, or movement in response to gravity. ... Biodiversity or biological diversity is the diversity of and in living nature. ... Speculation involves the buying, holding, and selling of stocks, bonds, commodities, currencies, collectibles, real estate, derivatives or any valuable thing to profit from fluctuations in its price as opposed to buying it for use or for income ( via dividends, interest etc). ...

Most agronomists believe that agricultural production will be mostly affected by the severity and pace of climate change, not so much by gradual trends in climate. If change is gradual, there will be enough time for biota adjustement. Rapid climate change, however, could harm agriculture in many countries, especially those that are already suffering from rather poor soil and climate conditions, because there is less time for optimum natural selection and adaption. The adoption of efficient new techniques tends to be far from obvious. Some believe developed nations are too well-adapted to the present climate. developing nations also would often have extensive social or technical constraints that prevent them from achieving sustainable production. Biota can refer to several things: The plant and animal life of a region; see biota (ecology) A municipality in Zaragoza, Aragon, Spain; see Biota (municipality) A superdomain in taxonomy; see Biota (taxonomy) Biota Holdings, the Australian biotech company This is a disambiguation page — a navigational aid which lists other... Natural selection is the process by which variants displaying favorable or deleterious traits end up producing more or fewer progeny relative to other individuals of the same population. ... A developed country is a country that is technologically advanced and that enjoys a relatively high standard of living. ... A developing country is a country with low average income compared to the world average. ... Sustainable agriculture integrates three main goals: environmental stewardship, farm profitability, and prosperous farming communities. ...

See also

• Global warming
• Global dimming

Global mean surface temperatures 1856 to 2004 Mean temperature anomalies during the period 1995 to 2004 with respect to the average temperatures from 1940 to 1980 Global warming describes an increase in the average temperature of the Earths atmosphere and oceans. ... A NASA photograph showing aircraft contrails and natural clouds. ...

References

• Fischer G., Shah M. and van Velthuizen H. (2002) "Climate Change and Agricultural Vulnerability". International Institute for Applied Systems Analysis. Report prepared under UN Institutional Contract Agreement 1113 for World Summit on Sustainable Development. Laxenburg, Austria

External links

• John Vidal and Tim Radford, The Guardian, June 30, 2005, One in six countries facing food shortage
• http://fr.news.yahoo.com/030512/202/36vt5.html
• http://news.independent.co.uk/world/environment/story.jsp?story=633349