low of 3.41 million square kilometers, 44 percent below 1981 to 2010 average. Effect on natural system:1)Agriculture:As the duration of crop growth cycles is related to temperature, an increase in temperature will speed up crop growth and shorten the time between sowing and harvesting. This shortening could have an adverse effect on the productivity of crops and fodder for livestock. Climate change can negatively impact crop yield by effecting agricultural inputs such as water supply for irrigation, amount of solar radiation and prevalence of pests. Extreme events, especially floods, desertification and droughts, can harm crops and reduce yields which are detrimental to national food security. 2)Ecosystems:Climate change is one of the important stressors that contribute to species extinction. As temperatures increase, many animal species move north to higher elevations, in both land and aquatic environments. While this means a range expansion for some species, for others it means moving into less hospitable habitat and increased competition with other species for food.
Changes in conditions such as temperature, light or nutrients, compel coral reefs to expel the algae living in their tissues and turn white in colour. This makes coral reefs less resistant to diseases which ultimately results in their death. Due to rising global temperatures, glaciers in the Arctic and Antarctica are disappearing which is affecting animals like polar bears and emperor penguins who rely on sea ice for breeding and feeding. The impact of climate change on a particular species like zooplankton can ripple through a food chain and affect a wide range of other organisms. Examples of species that are particularly climate sensitive include pika, polar bears and salmon. 3)Forests:Climate change directly and indirectly affect the growth and productivity of forests through changes in temperature, precipitation and amount of carbon dioxide in the air. Tree species generally migrate northward or to higher altitudes in response to increased temperatures, resulting in changes in the geographic distribution of forest types and new combinations of species within forests. Climate change contribute to an increase in the severity of insect outbreaks. Rising temperatures enable some insect species to develop quickly, alter their life cycles and expand their ranges northward. Lack of natural predators or pathogens as well as inadequate defense in trees, allow insects to weaken and kill trees. Climate change is projected toincrease the extent, intensity and frequency of wildfires. Warmer temperatures, coupled with decrease in water availability and dry soil, increase the risk of wildfire.4)Water resources:As temperature increases and the air becomes warmer, more water evaporates from land and sea into the atmosphere. At higher temperatures the atmosphere contains more water vapor, thus increasing the chance of heavy showers. Moreover, climate change disrupts the hydrological cycle and causes shifts in air and ocean currents, due to which moisture-laden air is not evenly