Scientist Ken Caldeira

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As we approach Earth Day 2014, one of the leading U.S. scientists on global warming weighs in on the climate change debate.

Since 2005, Ken Caldeira has held the position of senior scientist at the Carnegie Institution’s Department of Global Ecology at Stanford University. He's also a professor in the university's Department of Environmental Earth System Science. An atmospheric scientist, he studies the long-term evolution of the climate and global carbon cycle. Some of his research is focused on approaches to supplying energy services with a reduced environmental footprint. Caldeira has been featured in several publications for his climate work and, in 2013, co-authored with other leading experts an open letter to policy makers, calling on them to embrace nuclear power.


Tavis: The extent of the damage to the world’s resources due to climate change and just what action governments should take to halt this destruction continues, of course, to create acrimony. But as politicians argue about what should be done, what is clear to leading scientists is that immediate action must be taken to preserve the earth’s resources.

Among those sounding the alarm, Ken Caldeira from the Carnegie Institution’s Department of Global Ecology at Stanford University and one of the leading experts on climate change in our nation, and the world, for that matter. Dr. Caldeira, good to have you on this program.

Ken Caldeira: Good to be here.

Tavis: I want to make the best use of the time that I have with you, so let me just jump right in. How bad is the problem? And then we’ll jump to what we can do about it while politicians debate and argue. So how bad is the situation?

Caldeira: A hundred million years ago when the dinosaurs were around, the earth was hot, the ice caps were melted. Over the next decades, we can put out enough carbon dioxide to recreate the kind of climate that existed on this planet a hundred million years ago. So this is a radical alteration of the earth as we know it.

Tavis: Radical alteration in what way?

Caldeira: First of all, climates until generally shift towards the poles. The ice caps will start melting and sea levels rise. Typically, places that are already wet will get wetter. Places that are dry will get drier. And so there’ll be a fair amount of economic dislocation, but people are relatively adaptable. If we go to ecosystems, things like coral reefs, it’s been projected that they will not be sustainable within a few decades. Forests are threatened through the world.

Today, if you think about here in Los Angeles, the average temperature band is moving north about 30 feet a day. So we can maybe move 30 feet a day, but if you think of animals and trees and so on, there’s no way that ecosystems can keep up with this.

People who live already in gated communities might be able to survive well, but if you are in the Sahel in Africa or in a low-lying Pacific island, the people who are already in a marginal situation, climate change could be the thing that pushes them over the edge.

Tavis: To your point now, Dr. Caldeira, what do you make of the argument? How do you respond to the argument that the world’s worst polluters happen to be oftentimes, you know, the big guys and that the little guys in Africa and elsewhere end up suffering because of the damage that we are disproportionately doing to the environment and putting their lives at risk?

Caldeira: Well, this is a very good point. If we look at the projections for crop production that, in the northern mid latitude, so say in northern U.S., Canada, Russia, the growing season’s actually getting longer and crop yields are likely to go up in these regions.

But if we look at the tropical countries, already today crop production is limited by heat stress and it’s only going to get hotter and have more problems for growing crops, so in the same way that the north who created most of the problem, and the south will live with the brunt of most of the negative impact. Also, the rich countries obviously have more resources to deal with the problem.

Tavis: We have more resources to deal with the problem, but we’re really not at the level that we should. So oftentimes, I read these stories and accounts of where these, you know, smaller countries, these less industrialized nations, are really screaming really loud almost to the point of jumping up and down at these international conferences, which I’m sure you headline and speak at, where they’re demanding that those of us who are causing the problem and have the resources to do something about it do more.

How are we responding to that, we being the U.S.?

Caldeira: To my mind, we’ve done essentially nothing. I’m sure people will argue about this. We’ve done a little bit on the margins, but to really solve this problem, we need to transform our energy system into one that does not use the atmosphere as a waste dump.

You know, if you compress the atmosphere down to the thickness of water, the atmosphere would only be 30 feet deep. So it’s every tailpipe and smokestack is like going into 30 feet of water and it’s just these concentrations of CO2 are building up higher than it’s been for hundreds of thousands of years.

The amount of money that it would cost to transform our energy system, you know, it’s a huge amount of money. You know, we’re talking hundreds of billions of dollars a year. So it’s much less than the military budget, maybe a tenth of the healthcare budget. It’s a significant expenditure, but it’s the kind of thing that we do.

Tavis: So to your point before we get to what can be done, what ought to be done while the politicians, you know, contest the fact, the scientific facts, while they debate about this in Washington and beyond, what do you make of – and I’m not naïve in asking this – but what do you make of the infighting, the political fighting, that is, that still happens in Washington even though the science is telling us one thing?

Caldeira: I think the fundamental problem with the climate change problem, if we already had an energy system that didn’t use the sky as a waste dump and somebody said, “Hey, you can be 2% richer and all we have to do is acidify the oceans, melt the ice caps, you know, shift around weather patterns…”.

Tavis: You’re not saying this is all about money [laughs]?

Caldeira: I mean, the problem is that to use the cleaner systems that are more expensive and whoever uses it has to bear the cost and the benefits are distributed to everybody around the world and future generations, so you’re asking people in the here and now to spend money to benefit people around the world…

Tavis: But if they end – as a result of their not doing it, if they end up annihilating themselves and all the rest of us in the process, their business is going to be bankrupt and nonexistent at some point anyway.

Caldeira: Well, I might agree with you there, but I’m not running the show. I mean, there’s a problem in that people try to, you know, get what they can today locally and people aren’t thinking about the big picture and how to make things better for the long term.

Tavis: What do you make of the way that we are ignoring the warnings? The UN, as I referenced earlier in this introduction to this conversation, just put a new report out that something’s got to be done and done fast. Those warnings are not new. They’ve been coming for quite some time now.

I think of places like New Orleans and Katrina. The truth is that we were warned that this was going to happen in New Orleans. We were warned about any number of catastrophes that we’ve had to deal with. It’s one thing for a tornado to come out of nowhere. And even that has to do, you know, with the work that you do.

But how do we explain, justify, our absolute ignoring of the warnings that keep being given to us?

Caldeira: Well, it reminds me a little bit about the cigarette smoking and cancer. I mean, climate science has not fundamentally changed since I was in graduate school in the 1980s. In the same way that we knew for decades that cigarette smoking causes cancer, I mean, still we’re selling cigarettes all around the world.

And I think it’s been clear to climate scientists that, if you release greenhouse gases into the atmosphere, the earth’s going to heat up and it’s going to change the planet in unpredictable ways.

And the other thing is that it’s really just we’re talking about maybe 2% of our wealth or something to deal with this problem. The Clean Air and Clean Water Acts together is thought to cost around 1%, maybe half as much as solving the climate problem.

If you look at China, they have all these terrible pollution problems. Nobody wants to have to go back to having bad air pollution and everybody’s happy we’re spending that 1% to solve the air pollution problem. And if we could, you know, spend 2% and solve the climate problem, to me it seems like a no-brainer.

Tavis: So while they debate and argue, what do we do? Is this thing called geoengineering the answer?

Caldeira: Well, I think the fundamental thing we need to do is talk to the average person – which is why this program is excellent – that politicians do what they need to do to get re-elected and not necessarily what’s best for the public. So the public has to make politicians understand that they’re going to lose the election if they don’t vote the right way on this issue.

You bring up this idea of geoengineering which, in some forms, it’s kind of this last-ditch effort that, if things get really bad, what could we do in an emergency situation? So people have suggested that you could reflect some sunlight from earth and cool things down. And we saw in 1991 there was a huge volcano in the Philippines and the next year the earth cooled down despite the fact that greenhouse gases kept rising.

And we could basically – not we personally, but society could basically do what big volcanoes do and throw aerosols or little particles into the stratosphere to reflect sunlight. It would cool down the earth, but of course, there’s all kinds of risks, both political and environmental risks.

Tavis: The environmental risk make it worth trying?

Caldeira: To my mind, it’s worth researching to understand what the potential is. But things would have to get pretty bad before I’d be willing to do that. If people were starved – you know, earlier we talked about how crops might fail in the tropics.

If there are widespread famines in the tropics and there’s no way to get food to these people, I think then that’s the kind of thing where people would think, well, to save hundreds of millions of lives, maybe we should try something so radical as this.

Tavis: But at that point, would it be too little too late?

Caldeira: Well, I think it’s not a solution. I would look at it as giving, you know, morphine to somebody with cancer, you know, that you’re trying to do some…

Tavis: That’s my point, yeah.

Caldeira: You’re trying to do symptomatic relief. You’re not into solving the problem at that point. The solution to the problem is the transforming our energy system today and our transportation systems. You know, we should hope we’re not in that kind of deathbed situation that we want to deal with the morphine.

Tavis: Ken Caldeira is at the Carnegie Institution for Science at Stanford. Dr. Caldeira, good to have you on. Thanks for your insights and, hopefully, we can at some point sooner than later get some traction on this issue.

Caldeira: This was great. Thanks a lot.

Tavis: Good to have you on.

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Last modified: April 21, 2014 at 12:21 pm