Down East 2013 ©
Photography by Joan Myers
Professor Paul Mayewski, PhD, directs the Climate Change Institute at the University of Maine, a multi-disciplinary research unit with more than fifty faculty and staff and about thirty graduate students devoted to the study of climate change. Mayewski and his colleagues pioneered the use of ice cores — drilled from glaciers from Antarctica to the Himalayas to Greenland — to determine how the climate has shifted over tens of thousands of years, with residue from volcanic eruptions, meteor impacts, and acid rainfalls showing up as striations in the ice.
What does the institute do exactly?
Our focus is to understand how the natural climate system operates: what the impact of natural climate change is on humans and ecosystems, and then how much humans have impacted the climate system — not just temperature, but also changes in the chemistry of the atmosphere, toxic metals, all sorts of things.
How did you get involved with this research?
I started looking at glaciers and then eventually at ice cores in the late 1960s. At that time, our understanding of the climate system was that climate change was very, very slow, on the order of thousands of years, certainly hundreds of years.
How did your understanding change based upon the work you did in Greenland?
We sampled at very high resolution, continuously, and wherever we could, took all the measurements from a single ice core sample. As a consequence of that, we verified the existence of what is called abrupt climate change. [This discovery] suddenly changed the field of climate change and research because the climate does not operate slowly, it can operate very, very dramatically.
You use the term climate change, versus what was once known as global warming. Why the shift in terms?
I tend to use the term climate change not because it is the politically correct one, but because what is happening to the climate system is not just warming, it’s not even just global warming, it’s changes in the physical, chemical, and biological components of the climate system, and I think that climate change is a better overall term.
When you say that climate can change quickly, what time frame are we talking about?
Dramatic shifts in temperature, precipitation, storm patterns, in definitely less than a decade, if not less than two years. And that’s what we found in our records. And we are headed for abrupt climate change if in fact the models — even the conservative models of a degree and a half to two degrees centigrade [1.8 to 3.6 degrees Fahrenheit] in the next few decades, up to six degrees centigrade in the next few decades — are correct.
Can you explain why the change might come so quickly?
As you begin to stress a system more and more, at some point it switches grades, and that’s what abrupt climate change is, it’s pushing the system to a threshold at which it suddenly responds much, much faster than it did before. And greenhouse gas warming is a classic example. If you take a look at the levels of greenhouse gases today, compared to anything that we know existed in the last couple of million years, the highest level prior to industrialization is about 280 parts per million per volume. We’re up at the high 360s now.
Is that the famous scene from Al Gore’s movie where he’s on the lift, charting the rise in carbon dioxide in the atmosphere?
Yes. But that rise is important not just because it is a rise, but because it is a hundred times faster than any measured or even interpreted rise in CO2 in, for all we know, Earth’s history — certainly in the last few million years.
You mentioned sea level rise, too. Is that something else that we could see happening very quickly?
The last time Earth’s temperature was two degrees centigrade higher than today — which is what we expect by the end of this century — was about 130,000 years ago, and at that time sea level was five to ten meters [sixteen to thirty-three feet] higher than today.
Five to ten meters, did you say?
Yes. Let’s say two to ten meters, just to be safe. The last time that the temperature was three degrees centigrade [5.4 degrees Fahrenheit] higher than today was about 35 million years ago, that alone ought to be pretty interesting. Global temperature, and sea level was twenty to thirty meters [sixty-six to ninety-nine feet] higher than today.
You’ve taken a fairly prominent role in speaking about global climate change, not just in Maine, but all over the world.
I hope I’m not giving myself a high profile.
Rush Limbaugh hasn’t mentioned you yet.
I listen to him when I want to get amused on the road. He drives me insane, but I enjoy listening to him every now and then.
Why is there still a certain vocal segment of society that rejects the idea of human impact on the climate systems?
Well, some of the skeptics who have been involved in this process are very competent scientists, there’s no doubt about it. I think they did a lot for our community by forcing us to constantly look at this information more and more carefully. But we did, and basically the response has been an even stronger statement about the impact of human activity. But that whole period of debate lingers in the public’s memory. Number two, there are just always people who don’t like to believe what everybody else believes, simply to be contrary, or because it isn’t as convenient for them to believe — depending on how you live your life and how you make your money — to face the fact that humans have dramatically impacted the physical and chemical climate.
What is your personal vision for what Maine is going to be like in the future?
Five to fifteen years from now, I’m very optimistic. The negative parts: it will be warmer, it will be stormier. We probably will get more of our precipitation in the form of rain and ice which is not good — than snow. But I think we will have a cleaner environment. I think we will have an economically more viable environment. I think Maine could emerge as a leader in renewable energy resources. I think we will have a society that is much more efficient in terms of the way we use resources, one that understands its environment and lives in its environment much better. And I think health- and wealth-wise we will have a better quality of life. We have the choice right now to go in that direction.
It’s exciting to hear about the Obama administration putting stimulus money into fast railroads, renewable energy, the grid that is needed to deliver that renewable energy. Can we avoid everything that is going to happen in the future? No. But how much we pay, and whether or not we’re smart enough to turn this around into something better, is definitely under our control. That’s the beautiful part of this; it’s within our power to make these changes.