Global warming is a natural phenomenon. But the rate of global warming is accelerating by the rapid addition of Green House Gases (GHGs) as a result of burning of fossil fuels. Rising ambient temperatures, extreme floods, tornadoes, hurricanes, rising sea levels, glacial lake outbursts, droughts, deforestation and desertification are some of the manifestations of climate change due to global warming. The year 2015 has been the warmest year in the last 4000 years.