A new study says that the United Nations’ “doomsday” predictions for the environment, which sparked the Paris Accords, are “overstated” and unlikely to happen.
The U.N. had warned member nations that the earth’s temperatures could rise more than ten degrees within the next hundred years. That set off a mad push to limit carbon emissions and other pollutants worldwide. That movement culminated in the 2015 Paris Accords, signed by President Obama and every other industrialized nation.
President Trump has since pulled the U.S. out of that agreement, saying it unfairly punishes American business and does little to heavy polluters in third world countries and China.
Now, scientists at the University of Exeter say that is unlikely to happen. Even under the worst case scenario, they say, the temperature by the end if the century may only rise a few degrees.
Experts have found that the UN’s worst case scenario, that the world could warm by up to 6°C (10.8°F) by 2100, is unlikely to happen.
New calculations worked out the probable impact of greenhouse gases on global warming and found that more extreme scenarios will almost certainly not occur.
They reduce the range of possible end-of-century outcomes by more than half, researchers said, including the best and worst case scenarios.
The findings suggest that the Paris Agreement on climate change, which seeks to limit temperature increases to below 2°C, is more achievable than some claim.
Researchers from the University of Exeter used a new modelling method to examine how much the Earth’s average surface temperature will go up if the amount of CO2 in the atmosphere is doubled.
How effectively the world slashes CO2 and methane emissions, improves energy efficiency, and develops technologies to remove CO2 from the air will all determine whether climate change remains manageable or unleashes a maelstrom of misery.
But uncertainty about how hot things will get also stems from the inability of scientists to answer this simple question.
This ‘known unknown’ variable is called equilibrium climate sensitivity.
For the last 25 years, the UN’s Intergovernmental Panel on Climate Change (IPCC), the ultimate authority on climate science, has settled on a range of 1.5°C to 4.5°C (2.7°F to 8.1°F).
The Exeter team came up with a far narrower range of 2.2°C (3.9°F) to 3.4°C (6.1°F), with a best estimate of 2.8°C (5°F).
If accurate, it precludes the most destructive doomsday scenarios.
Lead author Peter Cox said: ‘Our study all but rules out very low and very high climate sensitivities.’
The landmark Paris climate agreement in 2015 called for capping global warming at ‘well under’ 2°C (3.6°F) compared to a pre-industrial benchmark, and pursuing efforts for a 1.5°C (2.7°F) ceiling.