LULU GARCIA-NAVARRO, HOST:
Now, there is no reasonable question that climate change is fueling these events and others around the globe, but there are questions about the details - why, even though the big picture is clear, the local effects of a warming planet are occasionally surprising. Michael Mann is a distinguished professor of atmospheric science at Penn State University, and the author of "The New Climate War: The Fight To Take Back Our Planet." We turn to him now because, you know, he's got a pretty good track record on climate predictions.
MICHAEL MANN: Well, it's a bit frustrating. As a climate scientist, the last thing you want to see is your predictions come true. And unfortunately, you know, despite the fact that decades ago we warned that if we continue to add carbon pollution to the atmosphere through the burning of fossil fuels that we would see not just an overall warming of the planet, the melting of ice and sea level rise, but more extreme weather events. And now the signal of climate change in the weather has emerged from the noise. What that means is that we can actually see climate change in the individual extreme weather events that are playing out right now across the northern hemisphere this summer. This is climate change.
GARCIA-NAVARRO: Is this a tipping point? Because what we used to hear about climate change is that these things will be happening 20 years in the future, 30 years in the future if we don't take the actions necessary. But what I'm reading from a lot of scientists is that this has accelerated in a way that is surprising.
MANN: The warming of the planet is pretty much proceeding as predicted. What's happening, though, is that some of the impacts are playing out faster than we expected. And it has to do with the fact that our models are imperfect. What we're seeing is that some of the impacts were underestimated because our models, for example, didn't have all of the critical processes involved in the collapse of ice sheets, which is so important to sea level rise.
Another area is extreme weather events. Now, the models capture some of the basic physics here that's relevant. You warm up the planet, of course, you're going to get more frequent and intense heat waves. You also have the potential for larger flooding events because the warm atmosphere can hold more moisture. But at the same time, that extra heat can dry out the ground and you get worse droughts.
But there's something else that's playing out with the events we've seen this summer, and that has to do with the behavior of the jet stream, the way the jet stream is slowing down and sort of getting stuck in place. And so you have these big weather systems that just lie over the same locations day after day - you know, on the West Coast, baking the soil, the heat. Back east, we've had a lot of rainfall because we've been stuck under sort of a low pressure center. And that is something that the models didn't really pick up on. They didn't predict that we would see this extra effect.
GARCIA-NAVARRO: Who should be held responsible for the events that we're seeing today? I mean, you've gotten a lot of backlash for your research and outspoken criticism of corporations who contribute to high carbon emissions.
MANN: Well, you know, let's take ExxonMobil. Back in the early 1980's, their own scientists, in an internal document that wasn't released to the public, actually referred to the consequences of business as usual, fossil fuel burning as catastrophic. This isn't Al Gore. This isn't the Intergovernmental Panel on Climate Change. This isn't me and my fellow climate scientists. This is ExxonMobil, the world's largest publicly traded fossil fuel company. And rather than coming forward with what their own scientists had found and engaging in a necessary conversation about how to avert these risks, they doubled down. They ended up getting rid of that research division, and they spent tens of millions of dollars in a massive disinformation campaign.
And so make no mistake about it; the fossil fuel industry bears much of the blame here. But there's enough blame to go around - politicians who have refused to rein in the fossil fuel industry, bad actors who have funded climate change denialism. It's what I call the inactivists, this community of entities, individuals and groups that have been waging a war against efforts to contend with the greatest challenge we face as a civilization - the climate crisis.
GARCIA-NAVARRO: I mean, and now we're seeing pushback about spending on climate change. Despite all the evidence, this is still politically toxic.
MANN: Yeah. We'll have to see what happens with this infrastructure bill that's being discussed. There are some really important climate measures in that bill. For example, a clean energy standard that would require utilities to produce up to 80% of their electricity from clean sources by 2030. And so there's some good stuff in that legislation. What remains to be seen will be, you know, if it survives.
GARCIA-NAVARRO: If things do not get better, what can we expect next?
MANN: There are two paths. One is a path of destruction. The other road is one where we do what's necessary, where we reduce carbon emissions by a factor two within the next decade, where the countries of the world come together. But that window is closing. We need to act now if we are to go down that far better path.
GARCIA-NAVARRO: Should we be watching for anything specific, like jet stream changes or any other indicators that could tell us which path we're headed on?
MANN: All eyes right now are on the behavior of the great ice sheets - the Antarctic ice sheet, the Greenland ice sheet. As goes those ice sheets, goes sea level rise. And in a worst-case scenario, we're looking at meters of sea level rise over a timeframe as short as half a century. The major cities, the coastal cities of the world will all be threatened. Tens to hundreds of millions of people could be displaced. So we have to make sure that we do everything we can to prevent that from happening. And that means we've got to reduce those carbon emissions dramatically.
GARCIA-NAVARRO: Michael Mann is the distinguished professor of atmospheric science at Penn State University. Thank you very much.
MANN: Thank you. It was a pleasure.
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