Warming may turn quarter of earth arid 

Warming may turn quarter of earth arid 

Context

Over a quarter of the world’s land could become significantly drier even if global warming is limited to the target of two degree Celsius, according to scientists including one of Indian origin

Threat could be curbed if temperature is limited to 1.5 degrees

The change would cause an increased threat of drought and wildfires.

However, limiting global warming to under 1.5 degree Celsius would dramatically reduce the fraction of the Earth’s surface that undergoes such changes.

Projections from 27 global climate models

• Researchers from University of East Anglia (UEA) in the U.K. and Southern University of Science and Technology (SUSTech) in China studied projections from 27 global climate models.
• They identified the areas of the world where aridity will substantially change when compared to the year-to-year variations they experience now, as global warming reaches 1.5 or two degree Celsius above pre-industrial levels.

Aridity

• Aridity is a measure of the dryness of the land surface, obtained from combining precipitation and evaporation.
• Aridification is a serious threat because it can critically impact areas such as agriculture, water quality, and biodiversity. It can also lead to more droughts and wildfires

Prediction

• Our research predicts that aridification would emerge over about 20-30 per cent of the world’s land surface by the time the global mean temperature change reaches two degrees Celsius
• But two thirds of the affected regions could avoid significant aridification if warming is limited to 1.5 degrees Celsius