Rainfall that mainly deals with the water cycle means a lot to living beings.There were 12% more record-breaking rainfall events from 1981-2010, compared to a scenario without global warming, peaking in 2010 with a 26% chance that the increase rainfall levels were brought about by climate change. Southeast Asia felt the biggest increase, with the increase going up to 56%. In Europe, the increase went up to 31% and in the central US, it reached 24%. ?One out of ten record-breaking rainfall events observed globally in the past thirty years can only be explained if the long-term warming is taken into account."For the last year studied,  it is even one event out of four, as the trend is upward."

Then the question comes how does global warming lead to more rain? According to the study in Climatic Change, based on the Clausius-Clapeyron equation, the higher the temperature of the air, the higher its potential to hold more moisture. This greater amount of moisture in the air then translates into stronger downpours.

In context of Nepal?s climate is influenced by the Himalayan mountain range and the South Asian monsoon (NCVST 2009). With the marked spatial and temporal variation, the average annual rainfall is 1800 mm. The monsoon rain is more in east and declines as it moves to west. Temperature varies with altitude and season,Temperature and precipitations have been the major climate variability and observed changes over time. According to a study conducted by OECD (2003) projects a scenario that mean annual temperature to increase by an average of 1.2 degree celsius by 2030, 1.7 degree celcius by 2050 and 3 degree celcius by 2100 compare to pre 2000 baseline. Similalry, the NCVST (2009 ) study using GCM and Regioonal Circulation Model (RCM) projects the mean annual temperature to increase by 1.4 degree celcius by 2030, 2.8 degree celcius by 2060 and 4.7 degree celcius by 2090. Although these study project inconsistent data, the reality is that the temperature is increasing in faster rate than the previous decades. Same studies show higher temperature increment for winter compared to the summer and monsoon seasons.Studies have shown that Nepal?s temperature increases 0.04-0.06 degree celcius annually The rainfall pattern mainly affects on the agriculture and life stock farming. Research has shown that changing in rainfall causes the problems like flood, drought which takes off many life and properties.

There are several international organization working for the awareness and reduction of consequences of flood and drought. One of the such organization is theUNISDR(The United Nations office for Disaster Risk Reduction). This organization promotes the various programs  integrated to the flood management. It also develop comprehensive strategies for flood risk management in a changing climate.