Scientific study: Domino effect could spur ‘hothouse earth,” speed up warming

Scientists both in Montana and nationally expect to see increasing insect epidemics because of global warming. (U.S. Forest Service)

(Courthouse News Service) Current goals for cutting greenhouse gas emissions might not be enough to curb global warming, according to a new study Monday indicating we’re headed for a domino effect that could speed up the warming process by four to five degrees and cause sea levels to rise.

Today, the planet’s average temperatures are just 1 degree above preindustrial levels, according to the authors of the study published in the Proceedings of the National Academy of Science. And while the Paris Climate Agreement set standards for carbon emission reductions, the study authors say a tipping point is coming, where the planet would begin to show natural feedback processes caused by an increase in global temperatures of 2 degrees that would lead to abrupt changes.

Those feedbacks could include the loss of Arctic summer sea ice, reduction of northern hemisphere snow cover, Amazon rainforest dieback, increasing bacterial respiration in the oceans and many others that would emit more carbon into the atmosphere, according to the study.

Co-author Johan Rockström, executive director of the Stockholm Resilience Centre, said this would be like a domino effect, where one change causes the another. Researchers call this a “Hothouse Earth.”

“It may be very difficult or impossible to stop the whole row of dominoes from tumbling over,” Rockström said. Places on Earth will become uninhabitable if “Hothouse Earth” becomes the reality.”

The effects of a “Hothouse Earth” include four to five degree rise in the average global temperature and massive fluctuation in sea levels, ranging from 32 feet to nearly 200 feet.

Their study shows how industrial-age greenhouse gas emissions force the climate and the rest of the planet out of balance, said Hans Joachim Schellnhuber, director of the Potsdam Institute for Climate Impact Research.

Once the planet passes a certain stress level there could be fundamentally and rapid change to the climate that could be irreversible, said Schellnhuber. Ultimately, this would tip the earth into a new mode of operation.

“What we do not know yet is whether the climate system can be safely ‘parked’ near 2 degrees Celsius above preindustrial levels, as the Paris Agreement envisages,” said Schellnhuber. “Or if it will, once pushed so far, slip down the slope toward a hothouse planet. Research must assess this risk as soon as possible.”

To avoid the “Hothouse Earth” described in the study, researchers say there would have to be improved forest, agricultural and soil management, biodiversity conservation, and technologies that remove carbon dioxide from the atmosphere and store it underground.