Warming climate threatens vast swathes of biodiversity
Average global temperatures are increasing as climate change continues to be a major crisis for our planet. A recent report published in Science, from Rachel Warren at the Tyndall Centre for Climate Change Research at the University of East Anglia in the United Kingdom, found that if global temperature increase cannot be limited to 1.5°C, and rises to 2°C, it just about doubles the risks associated with warming for plants, animals, and insects.
Now, in a reaction to that report, Guy Midgley – a world-leading expert on global change and impact on biodiversity – has published an insight article in Science detailing the effect this temperature change would have on biodiversity.
“Warming by more than two degrees will take the world into a temperature state that it hasn’t seen for several millions of years,” says Midgley, a professor in the Department of Botany and Zoology at Stellenbosch University, South Africa.
Based on current pledges by countries for limiting climate change, scientists predict a corresponding warming of roughly 3.2°C. If this were to occur, it’s estimated that the geographic ranges will be lost for 47% of insect species, 26% of vertebrates, and 16% of plant species.
Midgley believes that higher levels of warming may lead to systemic ecological simplification, where many “climate losers” are replaced by far fewer “climate winners.” A simplified ecological landscape could impact ecosystem services such as water quality, soil conservation and flood prevention. If insect populations were to decrease, it would likely mean fewer pollinators – which would be a major loss for plant species and human food production.
“We need to stay as close to 1.5°C as possible. That is really the conclusion from the Warren et al paper,” Midgley says. “So here is the irony. In order to achieve the 1.5°C target, we may well damage many of the habitats that support biodiversity in order to achieve a target that will save biodiversity.” What this means is that, even if governments and industry can limit warming to 1.5°C, recent research shows that large tracts of land would need to be made available for capturing and storing carbon. Expanding land use for carbon storage would likely threaten the habitats that occupy this land.
“There is way too much debate about the issue of climate change and whether or not it is real,” laments Midgley. “What we really need to be doing is debating how we solve this problem… if we fail to reduce our dependence on fossil fuels, we could literally move the world back 20 to 30 million years in the space of a century.”