Quarter of Earth's Land Threatened by Aridity, Drought, Wildfires

Summary

New research pub­lished in Nature Climate Change warns that a rise of 2°C in global tem­per­a­tures could lead to a sig­nif­i­cant increase in arid­ity on over a quar­ter of the world’s land, pos­ing threats of drought and wild­fires. The study sug­gests that keep­ing warm­ing below 1.5°C could ben­e­fit regions like South East Asia, Southern Europe, Southern Africa, Central America, and Southern Australia, where over 20 per­cent of the world’s pop­u­la­tion resides, and mit­i­gate the risk of arid­i­fi­ca­tion in two-thirds of the most at-risk areas.

New research warns that over a quar­ter of the world’s land could become sig­nif­i­cantly drier and at risk of arid­i­fi­ca­tion if world tem­per­a­tures con­tinue to rise. Rising tem­per­a­tures could also increase the threat of drought and the risk of wild­fires across the world.

The study was pub­lished on January 1, 2018 in the sci­en­tific jour­nal, Nature Climate Change.

As part of the research, an inter­na­tional team of sci­en­tists from the University of East Anglia in the U.K. and the Southern University of Science and Technology in Shenzhen, China looked at pro­jec­tions from 27 global cli­mate mod­els in order to iden­tify the areas of the world where arid­ity could sub­stan­tially increase if tem­per­a­tures reach 1.5 and 2°C above pre-indus­trial lev­els.

“Aridification is a seri­ous threat because it can crit­i­cally impact areas such as agri­cul­ture, water qual­ity, and bio­di­ver­sity,” said the study’s lead author, Chang-Eui Park of the Southern University of Science and Technology. ​“It can also lead to more droughts and wild­fires — sim­i­lar to those seen rag­ing across California.”

The researchers esti­mated that an increase in the aver­age world tem­per­a­ture of 2°C between 2052 and 2070 would result in a rise in arid­ity of 24 to 32 per­cent of the earth’s land.

“The areas of the world which would most ben­e­fit from keep­ing warm­ing below 1.5C are parts of South East Asia, Southern Europe, Southern Africa, Central America and Southern Australia — where more than 20 per­cent of the world’s pop­u­la­tion lives today,” warned another of the study’s authors, Tim Osborn from the University of East Anglia.

However, the study con­cluded that arid­i­fi­ca­tion could be avoided in two-thirds of the regions most at risk if aver­age world tem­per­a­tures were lim­ited to an increase of 1.5°C. This means that if appro­pri­ate action is taken to mit­i­gate cli­mate change, the threat of this neg­a­tive con­se­quence is sig­nif­i­cantly reduced.

The Paris Climate Agreement aims to limit the global aver­age tem­per­a­ture rise to below 2°C above pre-indus­trial lev­els, with a pre­ferred tar­get of 1.5°C. Close to 200 coun­tries signed the agree­ment and have pledged to reduce green­house gas emis­sions in an effort to reach this tar­get by 2050.

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