Climate change is likely to push species abruptly over tipping points as their geographic ranges reach unpredictable temperatures, according to a new study led by a UCLA researcher.
the new nature and its evolution The study predicts when and where climate change is likely to expose species worldwide to potentially dangerous temperatures.
The research team from UCL, the University of Cape Town, the University of Connecticut, and the University at Buffalo analyzed data from more than 35,000 animal species (including mammals, amphibians, reptiles, birds, corals, fish, cephalopods, and plankton) and seaweeds from every continent and ocean basin, along with projections climate up to 2100.
The researchers studied when areas within each species’ geographic range would cross a heat exposure threshold, defined as the first five consecutive years in which temperatures consistently exceed the maximum monthly temperature extreme experienced by a species across its geographic range over recent history (1850-1850). 2014).
Once a threshold of heat exposure is crossed, the animal won’t necessarily die, but there is no evidence that it can survive the higher temperatures—that is, research projects that could bring about a sudden loss of many species. habitats due to future climate change.
The researchers found a consistent trend that, for many animals, the heat exposure threshold would be exceeded for most of their geographic range during the same decade.
Lead author Dr Alex Piggott (UCL Center for Biodiversity and Environment Research, UCL Biosciences) said: “It is unlikely that climate change will gradually make environments more difficult for animals to survive. Instead, for many animals, there are spaces Much of its geographic range is likely to become uncommonly hot in a short period of time.
While some animals may be able to survive these high temperatures, many others will need to move to cooler regions or evolve to adapt, which they likely cannot do in such short timeframes.
“Our findings suggest that once we begin to notice that a species is suffering under unfamiliar conditions, there may be very little time before most of its range becomes inhospitable, so it is important that we pre-identify which species may be at risk in the future. coming decades.”
The researchers found that the extent of global warming makes a big difference: if the planet warmed by 1.5°C, 15% of the species they studied would be at risk of experiencing unusually high temperatures across at least 30% of the current geographic range in the region of one decade. , but this multiplies to 30% of species at 2.5 °C warming.
Dr. Piggott added: “Our study is another example of why we need to urgently reduce carbon emissions to mitigate the harmful effects of climate change on animals and plants, and avoid a massive extinction crisis.”
The researchers hope their study will help target conservation efforts, as their data provides an early warning system that shows when and where specific animals are likely to be endangered.
Co-author Dr Christopher Tresos (African Climate and Development Initiative, University of Cape Town) said: “In the past we have had snapshots to show the impact of climate change, but here we present the data like a movie, where you can see the changes unfold over time. This shows that the risk is for many “of species is a bit like everything, everywhere, all at once. By revitalizing this process, we hope to assist direct conservation efforts before it’s too late, while showing the potentially catastrophic consequences of allowing climate change to go unchecked.”
Researchers say that this pattern of sudden exposure may be an inevitable feature of living on a round planet — because of the shape of the Earth, there’s more room available for species in environments closer to the hot end than they’re used to, such as in low-lying regions or near the equator.
An earlier study by the same lead authors found that even if we halt climate change so that global temperatures peak and begin to fall, risks to biodiversity could persist for decades afterward. * In another analysis similar to the current study, they found that many species that encounter unfamiliar temperatures will live alongside other animals experiencing similar heat shocks, which can pose serious risks to local ecosystem function. **
The study was supported by the Royal Society, the Natural Environment Research Council, the National Science Foundation (US), the African Academy of Sciences and NASA.