According to IPCC( 2001),Climate change refers to a statistically significant variation in either the mean state of the climate or in its variability which may be due to natural processes or external forcing,or to persistent anthropogenic changes in the composition of the atmosphere or in land use.

                  The external forces which drives the climatic change may be natural such as volcanic eruption, solar activity or meteorites.Similarly,the anthropogenic factors which leads to the climate change are emission of green houses,particles/clouds,land change.Climate variability accounts for natural variability and climate change refers anthropogenic forcing(due to man-made changes in greenhouse gases,land surfaces,species distributions,etc)
                  Nepalese agriculture is vulnerable to  climate change due to the following reasons:

·       Monsoon dependent 80%rainfall Jun-Sep) agriculture

·       Around 21% of the agricultural land is only irrigated.

·       Fragile land condition.

·       Poor economy and lack of preparedness.

·       Unsustainable growth.

·       Lack of relevant data and study.

·       Implementation gap.

·       Dependency on natural resources.

·       Lack of preparedness.