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The world's top climate scientists have just released a landmark warning about the future of the planet. The headline — burning fossil fuels is already heating up the planet faster than anything the world has seen in 2,000 years. And it will certainly get much worse unless people around the world make some big changes. Joining us now to talk about all this is NPR's Dan Charles.
Hey, Dan.
DAN CHARLES, BYLINE: Hi, Ailsa.
CHANG: All right. So we've been hearing for quite some time now about how bad climate change is. So why is this report in particular getting so much attention?
CHARLES: This is the group that defines the scientific consensus. It's called the Intergovernmental Panel on Climate Change, or IPCC. Hundreds of scientists work on these reports. They take years to produce. Governments have to sign off on them. And this one is just the latest big reassessment of the climate that the IPCC has done, but it's the first one it's done in eight years. It also has the clearest, most confident conclusions that I have ever seen in an IPCC report. It says warming is happening — no hedging. We're seeing it already. We understand it much better, and it's speeding up.
CHANG: OK. How badly is it speeding up?
CHARLES: The scientists say the greenhouse gases that we have already put into the air have warmed up the planet so far by almost 2 degrees Fahrenheit. That's compared to a couple of centuries ago, before, you know, the massive burning of fossil fuels. It's going to keep warming up a bit because of the greenhouse gases we've already released. And then beyond that, it depends on us collectively. If every country, every business shifts away from burning gas and coal and oil over the next 30 years or so, we could probably limit this warming trend to a total of less than 3.5 degrees Fahrenheit or 2 degrees Celsius.
CHANG: Wait. So even if we really do shift away from fossil fuels fairly soon, we will still see more warming. I guess, then, what happens if we don't ever wean ourselves off fossil fuels?
CHARLES: Then it gets really dire. See; this warming trend appears to be accelerating as the greenhouse gases accumulate in the atmosphere. And if we keep burning fossil fuels, by 2100 — so within the lifetime of a child that's born today — the planet could be 5, 6, 7 degrees hotter...
CHANG: Wow.
CHARLES: ...Compared to pre-industrial times. That's degrees Fahrenheit. And that is truly a very different world.
CHANG: Right. And you're just talking there about average temperatures. But recently, I mean, we've been talking a lot about extreme weather events like heat waves, flooding, things like that.
CHARLES: Right. And one new thing in this report is it tries to put numbers on what that means. So, for instance, they say heat waves so extreme they used to only happen once every 50 years. Now they're happening almost five times more often. And in a world with lots of warming, they'd happen 40 times more often.
CHANG: Wow.
CHARLES: They'd also be hotter. Extreme droughts could double or quadruple in frequency. In a scenario with lots of warming, extreme storms could become three times more frequent and drop 30% more rainfall in a day.
CHANG: God. Well, here in the U.S., the Biden administration did promise to move the U.S. to net-zero carbon emissions by 2050. Would that actually be enough, Dan, to avoid some of the worst impacts of climate change? What do you think?
CHARLES: That goal —you know, zero carbon emissions by 2050 — that is exactly what's required. It would be a really huge accomplishment — you know, switching the electricity grid over to renewable sources of power like solar and wind or hydro or nuclear, using that clean electricity to power cars, heat homes. But so far, it's mostly just a promise. The administration has put forward some specific legislative proposals that would start down that path — a clean electricity standard. But that has been blocked by Republicans in Congress and some Democrats so far.
CHANG: OK. Well, world leaders are set to gather for a climate summit in November. Do you think this report was partly intended to influence what happens at that summit?
CHARLES: It's pretty clear that the scientists tried to make this report more accessible to the general public. It really does a much better job explaining the science in plain language. They say it is not their job to tell political leaders what they should do, but they definitely are saying this is what's at stake. Whatever political leaders decide, these are the likely consequences.
CHANG: That is NPR's Dan Charles.
Thank you so much, Dan.
CHARLES: Thank you.
