Climate Change: Hasn’t Warming Happened Before?


PAUL JAY: Welcome to The Real News Network. I’m Paul Jay, coming to you from Baltimore. We’ve been unfolding a series of interviews and discussions about climate change and the whole issue of the sense of urgency. And there’s–a conference has just taken place in Portland about just this. And now joining us from Portland is Valérie Masson-Delmotte. Valerie is based just outside of Paris at the Université de Versailles. And thanks very much for joining us, Valérie. VALÉRIE MASSON-DELMOTTE: Thank you for your invitation. JAY: So, first of all, just give us a little sense of what area you work in and a bit of a sense of your background, your credentials, your expertise. MASSON-DELMOTTE: So I’m a physicist. I first qualified in a PhD thesis on climate modeling, and over the last 20 years I’ve been working on past climate dynamics. I’m using data from ice cores from Greenland or Antarctica, and also from tree rings, and I’m using these data to test the ability of climate models to represent these past changes.

And I’m also trying to place the current changes and the projections of risks in a longer perspective. So I’ve been active in the scientific community. I’ve published more than 100 papers in the peer-reviewed literature. JAY: Okay. And you’re also–I know you’re speaking on your own behalf here, but you’re also–is it you’re going to be a coauthor, is it, of the next IPCC report? MASSON-DELMOTTE: So I was a coauthor of the 2007 IPCC report, on the paleo climate chapter, and I’m coordinating the next one for 2013. JAY: Before we get into sort of the meat of all this, let me remind our viewers that part of the series is about you. So we’re interviewing climate scientists, and then we’re asking you to send questions, comments, challenges, arguments.

And we will go back to Valerie, who will answer some of your questions. And we’ll keep going back and forth until we work our way through some of the scientific questions. And we will be organizing some debates as well. So, moving ahead, before we get into some of the scientific issues, let me just ask you: you know, the IPCC, under the auspices of the UN, has issued, you know, reports that represent the majority scientific opinion in the world. The reports get increasingly urgent and dire. And it’s almost like the more dire or urgent the reports get, the less traction it seems to be getting in terms of political action, political debate in United States, but not only United States: in Canada, and even in Europe. I mean, one of the things that accounts for it, I guess, is the economic crisis. But do you think that’s the only issue? Like, why isn’t there more sense of urgency here? MASSON-DELMOTTE: I think there is a clear link with the economical crisis, which drives policymakers to urgent and short-term issues rather than mid-term issues and changes required by mitigating climate change.

I also believe that for a number of people, climate change remains something that is sort of an intellectual construction, and I do not think that they are [incompr.] concerned. So there is, I think, a huge effort to be done by climate scientists, by the media, by educators in explaining what are our methods, what are the findings, and what are the risks, and how we can act to prevent climate change and to adapt to climate change. I think this is the major gap that we have, discussing with a lot of actors that are not that familiar with what is climate science. JAY: I guess part of the problem is when, you know, you’re losing your job or you might lose your house and economy’s so bad, and then you hear talk of possibilities of war, and there already are–there’s one war going on in Afghanistan, and there could be–there’s talk of war with Iran, and I guess it increasingly–climate change then seems to fade a bit in the background, ’cause it seems like, well, it’s so long-term before I might get affected that I’m going to worry about these other things first.

MASSON-DELMOTTE: So we have to be aware that the climate of the generation of our children–my daughters are 10 and 14–is already different from the climate we had when we were teenagers and the climate our parents had. So the change is real. We only see the beginning of these change, because we are continuing to inject greenhouse gases in the atmosphere. So we are committing ourselves to growing climate change in the next decades. That’s one point. And the other point is what you mentioned, economical crisis, international tensions. What we would like is a stable environment, and climate change is acting against that ideal. Climate change would oblige us to adapt constantly to a different environment. So this is why I believe that we have to incorporate this challenge amongst all the others that we have to face. JAY: Right. Okay. Well, let’s work through just two or three of the issues to get started with, and then, as people mail in–and you can send your questions or comments or challenges to contact (at) therealnews (dot) com or you can write them in the comments section below the video player.

So we’re going to work our way through two or three of the main skeptic arguments, ’cause Valérie’s been dealing in writing about this as well. So, Valérie, take us through what you think is sort of the most persuasive or prevalent skeptic argument. And what’s your take on it? MASSON-DELMOTTE: So I would summarize that in the following points. Some people think that climate is not changing. Some people think that it’s recurrent, natural. Some people believe it’s linked to the sun, for instance, and that it’s not man-made. Some people have doubts about our ability to model the complexity of the climate system, and so that results from climate models for the future are too uncertain to take into account. These are a few of the arguments I’ve heard and I’ve tried to discuss with. JAY: Well, pick up the last one, ’cause that’s one of the–I think, one of the ones that has got a lot of influence, that this is too difficult to model, and that this has happened before, these sort of spikes in warming of the Earth, and that until we know more and the modeling is clearer, there shouldn’t be such dramatic changes in the way we do business and earn our livings.

MASSON-DELMOTTE: So, coming back to your point about our ability to anticipate climate change, from past climates we know that despite its chaotic character, climate is predictable. We understand a lot of the past changes–the way the climate responded to changes in the orbit of the Earth on glacial and interglacial timescales, the response of the climate to changes in solar activity, in volcanic activity over the last centuries, for instance. And over these different timescales, we have a huge amount of data, and we can simulate these changes with the same climate models as are used for the future. So we know that these climate models which are based on physics of the atmosphere, of the ocean, of the land surface, and their interactions, they capture properly the first order of the responses. And what I mean, first order, I mean at the continental scale, at the hemispheric global scale, for temperature, for aspects of large-scale changes in precipitation, for instance.

So this is a very important aspect that we can simulate correctly, some of the past changes, which is for me a prerequisite for any trust in climate projections. JAY: Okay. Well, I’m sure we’re going to get mail and questions on this point, ’cause it’s one of the issues that’s really in contention. The other issue that’s in–an argument that’s made is–and I think, from my reading of it, at any rate, the majority of people that are skeptics do acknowledge the fact that there’s been a warming, although some people dispute that. But the argument is this isn’t the first time this warming has happened, and you can’t attribute–there’s no evidence to attribute that this warming is any different than previous warmings and that it’s essentially natural.

So how do you respond to that? MASSON-DELMOTTE: Okay. So there are different types of warming events at the local scale or at the global scale and through time. So you can consider the geological timescales, time of dinosaurs, for instance. And we know climate was warmer at that time. And we think that it’s caused by, at that time, two changes in the atmospheric composition with more greenhouse gases. And we can also model this type of climate changes on the deep times. Now we can also look at more recent timescales. And, for instance, about 10,000 years ago to 6,000 years ago we know the Arctic, for instance, was warmer than today by a few degrees. And this change at the time was caused by the orbit of the Earth around the sun that was different. It changes regularly because there’s not only the sun and the Earth, but also other planets.

And this we can calculate very precisely. We can take this into account in the climate models. And when we do so, we are able to simulate the patterns of these Arctic warming about 10,000 to 6,000 years ago. And now I’m moving to the last example I would like to give. That’s the climate of the medieval time period. And during this interval we have a number of high-resolution climate records. We know some areas were warmer than today, for instance, areas around Scandinavia, Greenland, or the North Atlantic. We also know that this warming was not the same everywhere. It was not that well detected, for instance, in Antarctica; it was not reported in what we know for the tropics. So we know that the spatial structure of the change was different from today. And now there’s an effort to model the climate evolution over the last 1,000 years, including this anomaly. And we think that this anomaly is caused by a lack of volcanic eruptions, more active solar activity, and also a coincidence of some natural modes of variability in the tropics and in the North Atlantic area. JAY: Well, we’ll–in the next time we do this–and I know we’re going to get some email about this, ’cause the issue of the spike in temperature during the medieval times, I think, is the one that’s used most often to say that why would you think it’s any different now than it was then.

And in this interview we just intend to sort of just very–begin the conversation. And these are complicated scientific issues, and to dig into it you need the time. So we will do a digging in just on this issue of why you think this isn’t a repetition of the medieval warming. MASSON-DELMOTTE: On this point, what I’d like to mention, of course, is that, you know, climate research is based on new data, new simulation, new process studies. And for the last 2,000 years there’s a very huge international effort in building new estimates of hemispheric temperatures, but also regional temperature changes. And this is done in the auspices of a program called past global changes. So there will be a lot of new findings in the coming months on this specific topic. JAY: Okay. Well, before we conclude this first part of this back-and-forth–and again, viewers, we’re inviting you to get in on this and ask your questions and make your challenges.

But just how urgent is it, in your opinion, the climate-change crisis? As we’ve said earlier in the interview and some of the other interviews, you wouldn’t know there even was a climate-change crisis if you listen to the debate in the U.S. presidential elections, and, for that matter, in the European elections, too. Economic crisis has overwhelmed any other discussion. But how–in your mind, how urgent is it? MASSON-DELMOTTE: Yeah, I think the position of policy actors is a little different in Europe. I know it quite well from France. I think there is a general consensus that climate change is real, that it questions our use of energy, and that there is an urgent need for mitigating climate change and reducing greenhouse gas emissions. So I think there is a political consensus in Europe on this issue. And this is the reason why it was not key in the political debates in the last years in many countries in Europe.

So, now coming to your point–and here we come out of my expertise as a scientist, and you ask me my opinion as a citizen, in a way, and I do believe that it is urgent to address this question, due to the fact that it is demonstrated that greenhouse gases act on climates. Today we are emitting, year after year, more and more greenhouse gases. So, so far the United Nations have been unable to control their emissions. So we are committing ourselves, our children, our grandchildren to climate change, because we keep changing the composition of the atmosphere, and the more we wait, the more the magnitude of the change or the need for action will be large. JAY: Okay. Well, so now join us for this discussion, the debate. Send in your questions, your challenges. You can do it at contact (at) therealnews (dot) com, or you can just do it below the video player here–there’s a comment box. And Valérie will join us again and again and again. We’re going to keep working our way through these issues one by one, and there will be debates.

So thanks very much for joining us. MASSON-DELMOTTE: Thank you. JAY: And thank you for joining us on The Real News Network..