More than a quarter of Earth's land surface will become "significantly" drier even if humanity manages to limit global warming to 2 degrees Celsius, the goal espoused in the Paris Agreement, scientists said Monday.
However, if average warming could be capped at 1.5 degrees, the problem would drop to about one-tenth the impact, sparing two-thirds of the land projected to be parched by the predicted 2-degree increase, according to a study published in Nature Climate Change.
With a 1.5-degree increase, parts of southern Europe, southern Africa, central America, coastal Australia and Southeast Asia - areas home to more than one-fifth of humanity - "would avoid the significant aridification" predicted with the larger increase, said study co-author Su-Jong Jeong of the Southern University of Science and Technology in Shenzhen, China.
"Accomplishing a 1.5-degree increase would be a meaningful action for reducing the likelihood of aridification and related impact," he told Agence France-Presse (AFP).
Jeong and a team used projections from several climate models with different warming scenarios to predict land-drying patterns.
The team found that at 2-degree change, which could occur any time between 2052 and 2070, would lead to 24 to 32 percent of Earth's total land surface becoming drier.
This includes land in all five climate zones - hyperarid, arid, semiarid, dry subhumid and humid.
But at 1.5, the lower aspirational limit written into the climate-saving Paris Agreement, the drying effect is reduced to between 8 and 10 percent, said Jeong.
The study authors added,"Because present mitigation policies do not appear to be sufficient to achieve the 1.5-degree goal, more efforts to mitigate global warming are therefore urgently needed to reduce the spread of aridification."