Man-made water vapour next climate threat
Scientists have warned that increasing levels of water vapour in the upper troposphere – a key intensifier of global warming – owing to greenhouse gases will amplify climate change impacts over the next decades.
Scientists at University of Miami’s Rosenstiel School of Marine and Atmospheric Science conducted the first study to confirm that human activities have increased water vapour in the upper troposphere. To find out the potential causes of a 30-year moistening trend in the upper troposphere, a region 3-7 miles above the earth’s surface, they measured water vapour in the upper troposphere collected by NOAA satellites. They showed that rising water vapour in the upper troposphere cannot be explained by natural forces such as volcanoes and changes in solar activity but by increased greenhouse gases.
Greenhouse gases contribute immensely in raising temperatures by trapping the earth’s radiant heat inside the atmosphere. This warming also increases the buildup of atmospheric water vapour, the most abundant greenhouse gas. The moistening of the atmosphere traps more radiant heat and contributes in amplifying greenhouse effect.
The study explains with the help of climate models that as the climate warms from the burning of fossil fuels, the concentrations of water vapour in the atmosphere will also increase due to that warming which result into trapping of more heat and further increases the Earth’s temperature.