As if submersion of coastal communities by rising sea levels weren't bad enough, scientists have recently added another frightening repercussion to climate change: the loss of species. Scientists are still quibbling over the number of species that may perish with rising temperatures, some claiming zero while others predicting a whopping 54%. In an effort to refine the predictions, Marc Urban, a professor of ecology and evolutionary biology at the University of Connecticut, has crunched the numbers, and although his results don't spell the end for over half the world's species, the numbers are still frightening.
Urban, who specializes in theoretical models that explore the dynamics between climate change and species distribution, examined over 130 studies linking the death of species to changes in global temperatures. Through meta-analysis, Urban was able to combine the results of previous studies to determine an overall risk assessment for loss of species, and what his analysis predicts is the death knell for 7.9% of all species. Put simply, that's one out of six species gone due to changes in global temperatures.
"The future global extinction risk from climate change is predicted not only to increase but to accelerate as global temperatures rise," Urban says in his recent article published this week in the journal Science. At present, the risk to species is 2.8%, but as the Earth warms, the number of species as risk increases. Urban predicts a global temperature rise of only 3°C could put up to 8.5% of species at risk, with amphibians and reptiles at the top of the list.
And the death toll won't be evenly distributed across the planet. Australia, New Zealand, and South America are predicted to suffer the most, since they are home to large numbers of endemic species occupying narrow ranges. South America alone could see a 23% decline, whereas North America and Europe fare better, although Urban admits that there are many regions of the world that have yet to be studied-regions that could face considerable threats.
So how can this information be applied? According to Urban, "We critically need to know how climate change will influence species extinction rates in order to inform international policy decisions about the biological costs of failing to curb climate change and to implement specific conservation strategies to protect the most threatened species."
Let's just hope the policymakers are listening.
