Recent Research: Climate Change May Force Numerous Species Past Sudden Thermal Thresholds

Climate change, according to a new study, could drastically push species past their thermal exposure limits, resulting in an immediate loss of habitat. This highlights the pressing need to reduce carbon emissions and focus on strategic biodiversity conservation.

The study, spearheaded by a researcher from University College London and published in Nature Ecology & Evolution, sheds light on how climate change may unexpectedly force species past critical limits by subjecting them to unprecedented temperatures in their respective geographic habitats.

The study offers predictions on the timing and places where species globally might confront potentially life-threatening temperature shifts due to climate change.

An international research team, hailing from UCL, the University of Cape Town, the University of Connecticut, and the University at Buffalo, examined data from over 35,000 animal species (including mammals, amphibians, reptiles, birds, corals, fish, cephalopods, and plankton) and seagrasses across all continents and ocean basins, in conjunction with climate projections up to 2100.

The researchers identified the periods and regions within each species’ geographical range where the thermal exposure threshold—defined as the initial five consecutive years with temperatures persistently above the species’ most extreme monthly temperature recorded over recent history (1850-2014)—may be surpassed.

Crossing the thermal exposure threshold doesn’t necessarily signify the extinction of a species. However, there’s no proof that they can survive higher temperatures, indicating the possibility of a sudden habitat loss for many species due to future climate change.

The researchers observed a common trend: for a large number of animals, much of their geographic range will surpass the thermal exposure threshold within the same decade.

Dr. Alex Pigot, the lead author from UCL Centre for Biodiversity & Environment Research and UCL Biosciences, expressed that climate change is not likely to gradually create harsher environments for animals. Rather, for many species, considerable parts of their geographic range are expected to become uncomfortably hot in a brief period.

He added that while some animals might survive these higher temperatures, many others will need to relocate to cooler areas or evolve to adapt—a task they probably can’t achieve in such short timeframes. He further emphasized that timely identification of species at risk is crucial, as once we start noticing their suffering, we may not have much time before the majority of their range becomes unsuitable.

The extent of global warming is a significant factor, the researchers found. With a planet warmer by 1.5°C, 15% of the studied species risk encountering unusually high temperatures across at least 30% of their current geographic range in a single decade. This risk doubles to 30% of species with a 2.5°C increase in temperature.

Dr. Pigot further emphasized the urgent need to cut carbon emissions to mitigate climate change’s detrimental impacts on fauna and flora and avert a large-scale extinction crisis.

The research team hopes that their study could inform and guide conservation efforts, providing an early warning system for when and where certain animals are likely to be at risk.

Co-author Dr. Christopher Trisos of the African Climate and Development Initiative at the University of Cape Town highlighted the innovative approach of their study, presenting the data as a “film” that shows changes over time. He also underscored the potentially devastating consequences of unchecked climate change.

The researchers theorize that this abrupt exposure pattern might be an unavoidable feature of inhabiting a spherical planet. The Earth’s shape provides more area for species in hotter environments, such as low-lying regions or near the equator.

Previous research by the same lead authors indicated that even if we manage to halt climate change, allowing global temperatures to peak and begin to decline, biodiversity threats could linger for decades. They also found that many species encountering unusual temperatures will be cohabiting with other species facing similar thermal shocks, posing significant risks to local ecosystem functionality.

This study, titled “Abrupt expansion of climate change risks for species globally,” was funded by the Royal Society, the Natural Environment Research Council, the US National Science Foundation, the African Academy of Sciences, and NASA.

Reference: Alex L. Pigot, Cory Merow, Adam Wilson, and Christopher H. Trisos, “Abrupt expansion of climate change risks for species globally,” 18 May 2023, Nature Ecology & Evolution. DOI: 10.1038/s41559-023-02070-4.

Frequently Asked Questions (FAQs) about Climate Change Impact on Species

More about Climate Change Impact on Species

• Nature Ecology & Evolution
• University College London (UCL) Centre for Biodiversity & Environment Research
• African Climate and Development Initiative, University of Cape Town
• National Science Foundation (US)
• NASA Climate Change and Global Warming