Quantcast
Climate
Strawberry dart frog, Dendrobatidae: Oophaga pumilio. Geoff Gallice / CC BY 2.0

Climate Change to Become ‘Greatest Pressure on Biodiversity’ by 2070

By Daisy Dunne

The combined effects of global warming and land-use change could cause the world's ecosystems to lose more than a third of their animal species by 2070, a new study finds.


Climate change is expected to become the largest driver of biodiversity loss by the second half of the century, the research finds, surpassing the effects of deforestation and agriculture.

The local loss of species could greatly impair the ability of ecosystems to function as normal, the lead author told Carbon Brief, which could, in turn, threaten natural services, such as pollination.

However, restricting global warming to 2C above pre-industrial levels—which is the limit of the Paris agreement—could reduce the risk facing the world's ecosystems, the author adds.

Wayward Wildlife

Rising temperatures and changing rainfall patterns are expected to make existing habitats inhospitable for many animal species. Biodiversity is also under threat from land-use change caused by agriculture, deforestation and land degradation.

The new study, published in Proceedings of the Royal Society of London B, considers how both of these threats could combine to affect ecosystems across the world in the coming decades.

The research finds that, in a future with relatively high amounts of global warming and land-use change, the number of animal species in the average ecosystem could fall by 38 percent, when compared to conditions from 1961-90.

However, some ecosystems are expected to face larger species losses than others, said study author Dr. Tim Newbold, a research fellow at the Centre for Biodiversity and Environment Research at University College London. He told Carbon Brief:

"Climate change is to become, perhaps, the greatest pressure on biodiversity and overtake land-use in terms of impacts on biodiversity. If you combine these things together, the predictions are—at least under business as usual—for very large losses of biodiversity."

Parallel Futures

For his research, Newbold used modelling to produce a set of maps showing the expected impact of global warming and land-use change—and where these threats could overlap—in different parts of the world.

His results were based on four possible future scenarios, known as the "Representative Concentration Pathways" (RCPs). Each scenario makes assumptions about a range of parameters, including the future rate of greenhouse gas release, the efforts made to combat climate change (mitigation) and the rate of global population growth.

The scenarios include: an "optimistic" scenario which assumes global warming is restricted to below 2C (RCP2.6); a scenario where warming reaches 2-3C (RCP4.5); a scenario where warming reaches 2.6-3.7C (RCP6.0); and a "business-as-usual" scenario where warming reaches 4-6C (RCP8.5). (Carbon Brief has previously described these four RCPs in more detail.)

The maps below show where losses are expected to be "high" (greater than 10 percent of species lost) as a result of climate change (orange) and land-use change (blue) for each scenario. Areas where high losses from global warming and land-use change overlap are also shown (black), as well as where species loss is expected to be low (grey).

Newbold (2018)

Expected biodiversity loss from climate and land-use change by 2070 under (top left to bottom right) RCP2.6, RCP4.5, RCP6.0 and RCP8.5. The maps include where losses are expected to be "high" (greater than 10% of species lost) as a result of climate change (orange) and land-use change (blue) for each scenario. Areas where high losses from global warming and land-use change overlap are also shown (black), as well as where species loss is expected to be low (grey).

The charts show that the combined impacts of climate change and land-use are expected to be highest under the "business-as-usual" scenario. In this scenario, land-use change is expected to cause biodiversity losses of 2 percent, while global warming is expected to cause losses of 29 percent.

Biodiversity losses are expected to be particularly high in the tropical grasslands and savannahs of southern Africa and southern America. This is because these regions are the most likely to be converted to agricultural sites, possibly for the production of palm oil, Newbold said.

The analysis also suggests that amphibians and reptiles could be disproportionately affected by both global warming and land-use change, when compared to mammals and birds.

Many amphibians have complex reproductive life cycles that rely on the availability of both land and freshwater. (For example, tadpoles are restricted to water while adult frogs live on land.) This reliance on multiple environments is likely to increase the group's vulnerability to climate change.

Reptiles could also be uniquely vulnerable to climate change. One reason for this is because reptiles rely on their external environment to regulate their body temperature, meaning they can overheat if temperatures are unusually high.

Bargaining with BECCS

The results show that the RCP2.6 scenario, which projects the smallest level of future climate change, leads to the second most negative land-use impacts on biodiversity.

This is largely because the scenario relies on considerable use of bioenergy with carbon capture and storage (BECCS) to limit the effects of climate change.

Put simply, BECCS involves burning biomass—such as trees and crops—to generate energy and then capturing the resulting CO2 emissions before they are released into the air.

In theory, this process could reduce the amount of CO2 in the atmosphere – making BECCS a "negative emissions technology."

However, using large-scale BECCS to limit warming to 2C could require up to 18 percent of the land surface to be converted to biomass plantations—which could pose a significant threat to biodiversity.

The new study, however, shows that when the impacts of global warming and land-use change are considered together, RCP2.6 still projects the lowest risks for biodiversity out of all of the scenarios.

This suggests that the large land-use costs associated with BECCS may be offset by the resulting reduction in climate change impacts.

However, it is important to consider that there could be other solutions for tackling climate change that would not take up large amounts of land, Newbold said. Such options would be the most beneficial for biodiversity, he added:

"The results of studies like this suggest that we should be looking for solutions that mitigate climate change that don't rely on using lots of land—because we know that has large impacts."

Reposted with permission from our media associate Carbon Brief.

Show Comments ()

EcoWatch Daily Newsletter

Sponsored
Animals
Tiger: Bernard DuPont (CC BY-SA 2.0); Wolf: John and Karen Hollingsworth /USFWS

Tigers and Wolves: The Reigning Cats and Dogs in Conservation?

By John R. Platt

Do the species most in need of conservation also receive the most scientific research?

Keep reading... Show less
Animals
A tiger in Dhikala, Nepal. Ranjith Kumar 2016 / CC BY-SA 4.0

Wild Tiger Population Nearly Doubles in Nepal

Thanks to dedicated conservation efforts, Nepal now has an estimated 235 wild tigers in the country, a nearly twofold increase from its baseline of 121 individuals in 2009, the World Wildlife Foundation (WWF) announced Sunday on the occasion of Nepal's National Conservation Day.

The South Asian nation is now on track to become the first country to double its tiger population as part of WWF's "TX2" goal to double the world's wild tiger population by 2022—the next year of the tiger on the Chinese zodiac.

Keep reading... Show less
Popular
North Carolina hog CAFO in Hurricane Florence floodwaters, Sept. 18. Larry Baldwin / Crystal Coast Waterkeeper / Waterkeeper Alliance

In a Warming World, Carolina CAFOs Are a Disaster for Farmers, Animals and Public Health

By Karen Perry Stillerman

In the aftermath of Hurricane Florence, I've joined millions who've watched with horror as the Carolinas have been inundated with floodwaters and worried about the various hazards those waters can contain. We've seen heavy metal-laden coal ash spills, a nuclear plant go on alert (thankfully without incident), and sewage treatment plants get swamped. But the biggest and most widely reported hazard associated with Florence appears to be the hog waste that is spilling from many of the state's thousands of CAFOs (confined animal feeding operations), and which threatens lasting havoc on public health and the local economy.

Keep reading... Show less
Popular
Models are seen backstage ahead of the Chika Kisada show during Milan Fashion Week Spring/Summer 2019 on Sept. 24. Tristan Fewings / Getty Images Entertainment / Getty Images

Milan Fashion Week Closes with ‘Oscars of Sustainable Fashion’

Milan Fashion Week closed on Sunday with the second annual "Green Carpet Fashion Awards" to promote sustainability in the fashion industry, Reuters reported.

Keep reading... Show less
Sponsored
Climate
An art installation of a polar bear crossing a New York City street. Thomas Jackson / Getty Images

7 Events to Check Out During the 10th Annual Climate Week NYC

Monday marks the start of the 10th annual Climate Week NYC. From Sept. 24 to the 30, non-profit The Climate Group has invited businesses, governments, nonprofit organizations, universities and art and music organizations to host a wide variety of affiliated events devoted to raising awareness and prompting action around climate change.

Keep reading... Show less
Health
Pexels

5 Ingredients for Health: Starting with Food

On Food Talk with Dani Nierenberg, Dr. Robert Graham—board-certified physician and founder of FRESHMed NYC—combines mainstream medical practices with therapies inspired by ancient wisdom: an integrative model of medicine. "My dad was a biochemist, so I grew up in this integrative model. One of the things that really stood out is my mom was distrustful about the conventional Western model. She still thinks she's the only doctor in the house, because food is such a powerful medicine, especially from her culture," said Graham.

Keep reading... Show less
Sponsored
Popular
Malte Mueller / Getty Images

When Profit Drives Us, Community Suffers

By David Korten

As I was reading the current series of YES! articles on the mental health crisis, I received an email from Darcia Narvaez, professor of psychology at University of Notre Dame. She was sending me articles being prepared for an anthology she is co-editing with the working title Sustainable Vision.The articles present lessons from indigenous culture that underscore why community is the solution to so much of what currently ails humanity.

Keep reading... Show less
Popular
The Revelator

Interactive Map: Air Pollution in 2100

By Dipika Kadaba

Having a little trouble breathing lately? That's no surprise. Air pollution is already bad in many parts of the country, and climate change is only going to make it worse. Even though many industries are reducing their emissions, a warming climate could actually offset these reductions by intensifying the rates of chemical reactions and accumulation of pollutants in the environment.

Keep reading... Show less
Sponsored

mail-copy

The best of EcoWatch, right in your inbox. Sign up for our email newsletter!