There’s still a way to reach global goal on climate change

If nations do all that they’ve promised to fight climate change, the world can still meet one of two internationally agreed upon goals for limiting warming. But the planet is blowing past the other threshold that scientists say will protect Earth more, a new study finds.

The world is potentially on track to keep global warming at, or a shade below, 2 degrees Celsius (3.6 degrees Fahrenheit) hotter than pre-industrial times, a goal that once seemed out of reach, according to a study published Wednesday in the journal Nature.

That will only happen if countries not only fulfill their specific pledged national targets for curbing carbon emissions by 2030, but also come through on more distant promises of reaching net zero carbon emissions by mid-century, the study says.

This 2 degree warmer world still represents what scientists characterize as a profoundly disrupted climate with fiercer storms, higher seas, animal and plant extinctions, disappearing coral, melting ice and more people dying from heat, smog and infectious disease. It’s not the goal that world leaders say they really want: 1.5 degrees Celsius (2.7 degrees Fahrenheit) since pre-industrial times. The world will blast past that more prominent and promoted goal unless dramatic new emission cuts are promised and achieved this decade and probably within the next three years, study authors said.

Both goals of 1.5-degrees and 2-degrees are part of the 2015 Paris climate pact and the 2021 Glasgow follow-up agreement. The 2-degree goal goes back years earlier.

“For the first time we can possibly keep warming below the symbolic 2-degree mark with the promises on the table. That assumes of course that the countries follow through on the promises,” said study lead author Malte Meinshausen, a University of Melbourne climate scientist.

That’s a big if, outside climate scientists and the authors, say. It means political leaders actually doing what they promise

The study “examines only this optimistic scenario. It does not check whether governments are making efforts to implement their long-term targets and whether they are credible,” said Niklas Hohne of Germany, a New Climate Institute scientist who analyzes pledges for Climate Action Tracker and wasn’t part of this study. “We know that governments are far from implementing their long-term targets.”

Hohne’s team and others who track pledges have similarly found that limiting warming to 2 degrees is still possible, as Meinshausen’s team has. The difference is that Meinshausen’s study is the first to be peer-reviewed and published in a scientific journal.

Sure, the 2-degree world requires countries to do what they promise. But cheaper wind and solar have shown carbon emissions cuts can come faster than thought and some countries will exceed their promised cuts, Meinshausen said. He also said the way climate action works is starting with promises and then policies, so it’s not unreasonable to take countries at their word.