Increasing concentration of green house gases in the atmosphere have already been documented and proved undoubtedly. Global Climate as a whole, is a phenomena which is affected or balanced by many interlinked processes of various systems in atmosphere, ocean etc. Considerable concerns have been made regarding human induced climate change as changed weather will certainly going to affect agriculture. Previous ice core samples and ocean sediments depicts climate change events in history also. Nevertheless, the present scenario of global warming is supposed to be due to escalating concentration in atmospheric green house gases, which change the heat balance of the earth surface. The recent trend includes in global sea level and northern hemisphere snow cover, rising global mean temperatures and increased extreme climatic events in India during last few decades. Various General Circulation Models have projected the global warming could shift temperature zones, rainfall patterns and agricultural belts. Receding glaciers due to global warming are also reported in case of various studies on Dokriani glacier in Gangotri valley, Parbati glacier in Himachal’s Beas basin and other different glaciers. The glaciers are also breaking. The warming may account for about 0.8 to 3 inches of the total expected sea level rise, while the retreat of glaciers and ice may account for about 0.8 to 2 inches. As predicted by the various climate models, by 2100 a rise of 1.8 to 4oC is expected in the average global temperature. Productivity of most cereals would drastically affected due to increase in temperature and decrease in water availability. Increased events of droughts and floods are likely to increase production variability. To mitigate the adverse effect of climate change, conservation of the natural resources and their effective use, proper water conservation techniques and change in the priorities in research and technology should be ensured in future. Adoption of techniques like minimal tillage, residue management and increased production and use of biofules may be helpful in reducing the Green House Gases emission into the atmosphere.The strategies must include breeding of drought and water stress tolerant varieties,improvement in irrigation and water use efficiency of crop plants, reducing atmospheric concentration of greenhouse gases by adoption of various ecofriendly techniques, increase in productivity of existing farmed area and reduce deforestation and paddy plantation which contribute to CH4 emission and modification of microclimate for increasing productivity of crop.

Keywords: Changing climate scenarios; Global climate or in regional climates.