51社区黑料

Up to 36 per cent of animal habitats on land could be exposed to multiple extreme climate events by 2085, according to a new international study.

A 51社区黑料 researcher was part of an international team that used climate impact modelling to project how much of the planet鈥檚 land animals鈥� habitat would experience multiple extreme heat waves, wildfires, droughts or river floods under low- to high-emissions scenarios over the next 60 years.

鈥淲e were looking at what percentage of amphibian, bird, mammal and reptile land habitats would experience repeated extreme events such as back-to-back heat waves or a heat wave followed by a wildfire,鈥� says Sian Kou-Giesbrecht, a contributing author of the study.

鈥淲hen extreme events happen again and again or close together, it leaves very little time for species to adapt or recover.鈥�

Led by the Potsdam Institute for Climate Impact Research (PIK) and published in Nature Ecology & Evolution,  used models to translate climate projections into climate impacts.

At low emissions, in line with the Paris Agreement limiting warming to below 2 degrees C, exposure stays within moderate levels at nine per cent. But experts say if we move into high鈥慹missions scenarios, projections illustrate a massive increase with 36 per cent exposed to extreme events.

鈥淭his study shows that even robust conservation strategies can only go so far,鈥� Kou Giesbrecht says. 鈥淎t some point, limiting biodiversity loss depends on climate change mitigation 鈥� specifically, reducing fossil fuel emissions.鈥�

The findings build on other studies that show similar increases in human exposure to extreme events under high emissions scenarios, she adds.  

Heat waves, wildfires pose the greatest threat

Researchers found heat waves accounted for the largest projected impact. Under high鈥慹missions scenarios, 74 per cent of land species鈥� habitat ranges will be exposed to heat waves by 2050. 

Extreme wildfires are projected to be the second most prevalent event, affecting 16 per cent of animal habitat on land by 2050 and increasing to 25 per cent by 2085 in high-emissions scenarios.

Species鈥憆ich regions such as the Amazon basin, Africa and Southeast Asia are projected to be among the hardest hit. However, the study likely underestimates future exposure in Canada, Kou鈥慓iesbrecht says.

That is largely because current global climate models do not adequately simulate boreal and high鈥憀atitude wildfire behaviour. Canada鈥憇pecific modelling is underway in other research, she adds.

鈥淐anadians are understandably proud of our beautiful lands and the species we share them with,鈥� she says.

鈥淲e can help protect them by staying within Paris Agreement targets to limit warming, alongside robust conservation strategies that account for escalating climate impacts.鈥�