From record-low temperatures to an increase in natural disasters, the effects of climate change are considered visible to some and controversial to others. However, a meta-analysis by Mark Urban, a University of Connecticut ecology and evolutionary biology professor, has revealed the impact of global warming is more tangible and destructive than previously thought.
According to the study, published in the May 1 issue of the journal Science, if global temperatures continue to rise at their current pace, up to one in six species will be threatened with extinction.
“The most surprising finding for me was that extinction risk did not just increase with temperature rise, but accelerated, curving upward as the Earth warmed,” Urban said in an emailed statement. “We need to be even more cautious in our calculations of the effects of climate change on future biodiversity.”
The study estimates that if the Earth continues to warm at its current rate, it would warm nearly 40 degrees F by 2100. Consequently, the species extinction rate would rise to 16 percent. Predictions of extinction risks caused by climate change vary greatly in the scientific community, according to the study.
“My hope is that my results provide a clearer picture about what will happen given different future climate change scenarios,” Urban said. “If we continue on our current course, climate change could threaten one in six species. However, we can limit losses if we choose to rein in greenhouse gases.”
In addition to enacting conservation laws, Urban hopes the study will be used to predict further consequences of climate change.
“I also hope to encourage the further development of extinction models so that we can continue to improve their accuracy and their ability to pinpoint which species are most affected by climate change and thereby require conservation actions,” Urban said.
Gordon Bromley, a research assistant professor at the University of Maine’s Climate Change Institute, praised the meta-analysis for its novelty.
“No one’s ever done it before,” Bromley said. “To pin the blame on our actions in such a stark way is appropriate but entirely new. We’ve heard a lot about how climate is going to keep changing, but we’ve never looked at what the impact will be on species.”
However, the rising extinction rate may be the result of other natural and man-made causes, according to Bromley.
“My question is whether this is just due to climate, whether the climate changing will cause the extinctions, or whether that’s simply symptomatic of other things that might more directly affect species, such as the acidification of the ocean and habitat loss,” Bromley said. “Weather, for example, is chaotic. Our actions will make more chaotic weather. It’s a combination of [the] human and natural chaos of the system.”
The meta-analysis can be practically used to assess the consequences of climate change, according to Benjamin Zuckerberg, an assistant professor of wildlife ecology at the University of Wisconsin-Madison.
“I thought it was very interesting,” Zuckerberg said. “Mark did a really nice job of being able to look at [and] bring together what has been the different number of meta-analyses to try and look at some of the factors that might be most influential in trying to accurately assess extinction risk.”
The meta-analysis also revealed that the risk for higher extinction rates is greatest in South America, Australia and New Zealand. Species in other regions, such as North America and Europe, have adapted due to varying temperatures and climates, according to Zuckerberg. Certain species, such as amphibians, are more vulnerable and only reside in areas that are at risk for higher temperatures.
“Along equatorial regions, climate in general is less variable compared to North America and parts in Northern Europe where there is a lot of seasonality,” Zuckerberg said. “Even a half-degree Celsius change in South America [has a] fundamentally different [impact] than the same amount [of] change in North America.”
The political debate surrounding climate change cripples the scientific community’s ability to work with the public to create change, according to Zuckerberg.
“We have to continue to avoid politicizing climate change,” Zuckerberg said. “We have to continue to emphasize the science—that there is no scientific debate or disagreement among scientists about the validity of climate change and its impact on species.”
Public attention should be directed toward conservation efforts, Zuckerberg said.
“[It’s important that we are] having a discussion about how we actually go about reducing emissions [and] how we go about thinking about conservation of natural habitats, how we start doing climate-smart conservation,” Zuckerberg said. “[These] are really important conversations to have as a society. We need to continue having those conversations without the political chatter that goes on with climate change work.”
Zuckerberg said he hopes the meta-analysis will increase awareness of the realities of climate change.
“There are species we will lose in the coming years that are [a] consequence of modern day climate change,” Zuckerberg said. “Extinction is a very real possibility for species. We have the ability to control or mitigate these effects by changing society’s behavior.”