As climate warming drives more extreme weather, ‘everything we care about is on the line’

Hurricane Hilary dropped a record 13 inches of rain in 24 hours on the Mexican state of Baja California Sur before turning into a tropical storm, barreling up the bathwater-hot Gulf of California and bringing record rainfall to Southern California.ALEX WELSH/NYT

INTO THE RED: Climate and the fight of our lives

The extreme weather this year has been relentless. Currently, a heat dome over the southeastern United States is sending temperatures well above 100°F, more than 1,000 fires are actively burning across Canada, and some 100,000 people in Pakistan have been evacuated after a river overflowed and sent up to six feet of water across roadways.

Meanwhile, hurricane season is just ramping up, ocean temperatures are at record highs, and parts of Greenland’s ice sheet are melting at a record pace.

This is life on planet Earth that is roughly 2°F warmer than preindustrial times. Even for climate scientists who have long warned this was coming, the onslaught of crises has been nothing short of shocking.

What happens next, experts say, is up to us.

“I’m increasingly hopeful that the solutions are out there, that we’re starting down the right roads,” said Max Holmes, chief executive of the Woodwell Climate Research Center in Falmouth. “We’re starting to do the things that we’ve known we needed to do for a super long time, but we’re actually starting to do them in a bigger way.”

Those include adopting clean energy at a larger scale, passing last year’s first-ever national climate legislation, the Inflation Reduction Act, and pressuring private corporations to prioritize emissions cuts.

But it’s late, Holmes and others are quick to acknowledge, and there is so much more to be done.

Last fall, the UN Environment Programme found the world is on track to be 5°F (2.8°C) warmer by the end of the century — a trajectory that far exceeds the goal of 2015′s Paris Agreement, which included commitments to keep warming below 3.6°F (and, ideally, to 2.7°F). Each fraction of a degree brings with it more extreme weather. And it’s not a linear increase — the pace ramps up the warmer it gets.

“The ratcheting up of extreme events is kind of a missed message within the public domain,” said Scott Kelly, an economist and senior vice president of the climate-analytics firm Risilience. “Each .1 degree is going to be a multiple increase in extreme weather events as we move forward.”

Which is to say that the world’s response to climate change will not just be measured by whether it can constrain warming to the specific thresholds of the Paris Agreement. Every increment of a degree of additional warming — and every increment avoided — matters.

The difference between the upper and lower limits of additional warming set as targets in the Paris Agreement may seem small, for instance, but the ramifications of reaching the 3.8-degree threshold instead of holding steady at 2.7 degrees of warming would be massive. It would be the difference between saving some coral reefs or losing almost all of them; between preventing the collapse of the Greenland and Antarctic ice sheets or as much as 30 feet rise in sea level as those crucial glaciers melt; between 14 percent of the global population being exposed to severe heat at least once every five years or 37 percent.

“We’re still kind of at the start of this thing,” said Holmes. “What we’re seeing right now — even if we got our act together right away, there’s a lot more coming. We haven’t seen the worst of it.”

One challenge scientists are grappling with is that even as they are racing to understand the sequences of climate change on the future, the effects from current levels of warming are much worse than originally expected. As the science of climate change has gotten more refined, the Intergovernmental Panel on Climate Change, the UN’s body for assessing the science on climate change, has changed its projection for what to expect, finding that extreme weather impacts should be expected sooner, with less warming than previously thought.

Later this fall, the world’s climate negotiators will gather in Dubai for the 28th United Nations Climate Change Conference, known as COP28. Optimists will point to the incremental progress made each time these leaders gather, starting with the Paris Agreement and continuing through the commitments to continually revise and ramp-up national climate pledges and to address the glaring inequity of the climate crisis, in which the people and nations that emit the least greenhouse gasses are often the most impacted.

Others might counter by pointing out the president of the United Arab Emirates’ national oil company will be presiding over COP28, casting a pall over international talks that had already been considered compromised by fossil fuel interests for years. They might also mention how at this gathering last year, the agreement signed by world leaders failed to call for the phasing out of fossil fuels, and that greenhouse gas emissions — largely driven by the burning of fossil fuels — increased rapidly in 2022.

But there is one underlying difference this year, said Rachel Cleetus, the policy director of the climate and energy program at the Union of Concerned Scientists. “It doesn’t matter where in the world they’re coming from, they will have — this year, firsthand — seen in their communities the impacts of climate change,” said Cleetus, who has attended the climate talks since 2009.

This year, Cleetus hopes, will see the breakthrough — the connection between the world’s dependence on fossil fuels, and the devastation being felt through extreme events. “Everything we care about is on the line now,” she said.