Glaciologist Dr. Paul Mayewski, Director of the Climate Change Institute at the University of Maine, has led dozens of international research teams into the remote places of the earth to gather historical climate records still frozen in ice. The extreme conditions of the Antarctic, Himalayan, Patagonian and Greenland ice sheets compound the difficulty of extracting these information-rich ice cores and require exceptional leadership skills. Mayewski's expertise extends both to expedition management and the collection and preservation of the ice cores for later analysis. Not only does he thrive in the rugged environments in which he pursues his craft, but he has also contributed to 300 reviewed publications and has pioneered comprehensive climate models by calibrating and interpreting the data obtained from these locations.
Further, his study provides us with insights into the atmospheric chemical changes now and in the past (both before and since the industrial revolution and our unrestrained use of fossil fuels), historical patterns of previous abrupt climate change events (ACCE’s), and the correlation between these dramatic climate changes and the disruptions of previous civilizations. Mayewski and author Frank White have thoroughly documented these patterns in their book The Ice Chronicles: The Quest to Understand Global Climate Change.
SuperConsciousness Magazine spoke with Dr. Mayewski about glaciology, the correlations between temperature and CO2 levels, ACCE’s, and the collapse of societal and agricultural productivity.
SC: Glaciology is one of the newer interdisciplinary earth sciences. Could you give us a historical overview?
PM: The field of glaciology has been around for a little bit more than 100 years. It really started as a field dedicated to understanding why glaciers change in size over time and how they move. It wasn’t until probably the late 1950s that ice core research began. Ice coring was initially conducted to make holes in the ice and then to look at the defamation of those holes. Later we looked at the composition of the cores themselves.
The core properties differ as you drill down from the surface. And one of the things that occur, of course, is that the snow changes from very light, fresh snow found at the surface condensing down into hard packed ice over time with trapped air bubbles inside. This compacted ice provides us with a historical record much like the rings of trees. The yearly ice layers will also contain airborne particulate, which we can accurately correlate with events like the eruption of volcanoes or dust storms.
What’s important is that these measurements give us proxies for past temperature, for past precipitation, and for past atmospheric circulation patterns and past chemistry of the atmosphere. For example we can reconstruct the behavior of an El Nino. We can reconstruct marine storm frequencies. From these ice cores we can also identify changes in terrestrial biological activity or biomass burning events. We can even pick up radioactive fallout.
However, within the trapped air bubbles are atmospheric gases, and from these gases, we are able to track levels of the greenhouse gases, like CO2, carbon dioxide.
SC: And advancing technology aided scientists with dating the ice cores and analyzing the gases.
PM: For instance, it is the hydrogen and oxygen isotopes that provide us with a history of temperature. When each slice of the ice core is melted, we are able to calculate the different atomic weights of these elements by analyzing the ratio of heavier to lighter isotopes. And by about the late 1970s and early 1980s it became possible to look at dissolved ions in the ice and tell the concentration at very, very low levels … parts per billion, parts per quadrillion.
"As for greenhouse gases like CO2, we started analyzing those in the 1990s from air bubbles deep in the ice. Whereas temperature is measured using melted ice, the key to the greenhouse gas analysis is the measurement of trace gases within the air bubbles within the ice, well-preserved samples of earth's atmosphere from the past"
SC: And once the greenhouse gas data was analyzed and correlated with the temperature data, everyone was surprised to see that for hundreds of thousands of years, temperature and greenhouse gas levels have varied in sync with each other in relatively predictable, cyclic patterns.
PM: Yes, the correlation between the greenhouse gases and temperature certainly is remarkable. When this first hit the scientific community, it was very, very exciting because it validated what was thought to be true theoretically about greenhouse gases and temperature at the surface of the earth. And the cycles are consistent. For instance, the Greenland ice sheet has gone through 100,000-year cycles of which 90,000 years show a colder trend and for the last 12,000 years there has been a warming cycle.
SC: These data have given us an understanding of the dynamic nature of climate - it's not just about temperature - but a complex system of continuous change, checks and balances, adjustments and adaptations. What your book shines light on is the range of action and reaction the earth balances to maintain the equilibrium that allows life to sustain itself.
"The correlation between the greenhouse gases and temperature certainly is remarkable. When this first hit the scientific community, it was very, very exciting because it validated what was thought to be true theoretically about greenhouse gases and temperature at the surface of the earth. And the cycles are consistent"
PM: That’s exactly what’s happening. As we approached the end of the 20th century and into the 21st century, greenhouse gas levels are rising so high that they are becoming more and more the dominant control on climate, and while they’re still not the dominant control we are approaching that point. I think it's very important for readers to understand that scientists know that the greenhouse gas levels are extraordinarily high and increasing extraordinarily fast due to human activity, far above natural levels. We shouldn't be seeing the dramatic changes of the past couple of decades the way we’re seeing Artic summer sea ice melt or around the outer regions of Greenland if climate were still just operating within the natural state of the climate system.
SC: And there is ice core evidence that dramatic changes in climate, known as Abrupt Climate Change Events (ACCE's) have occurred very quickly, in some cases in as little as two years.
"As we approached the end of the 20th century and into the 21st century, greenhouse gas levels are rising so high that they are becoming more and more the dominant control on climate, and while they’re still not the dominant control we are approaching that point"
PM: Right. Despite the fact that it was a big, big item in the press in the early 1990s, most people either forgot about it or they don’t have a real context for understanding the implications. But these ACCE's are very important. Because, relative to now, the most dramatic of those occurred in the North Atlantic and are recorded in the Greenland ice sheet.
Certainly the two most important findings from the ice cores, the greenhouse gas temperature association and the identification of ACCEs, are significant because they have raised our understanding of climate change from a state in which we assumed that climate change operated so slowly that it doesn’t really matter what humans did because climate couldn’t change that fast, to undersanding that greenouse gas levels are intricately related with temperature change and that temperature, precipitation, and storm patterns can change dramatically in very short periods of time.
The bottom line is that over the last 100,000 years there have been many abrupt climate change events. And, the ones that have occurred in the last 10,000 years are, of course, particularly interesting because this is the period when recent civilization emerges and when the surface of the planet's forests, plains, glaciers, etc., begin to look as they do today. We've found places in the record where abrupt climate change happened in less than two years! And if you take a look at the last 7,000 years at the ACCE's and major transitions in society, you get remarkable, remarkable correlation.
"Greenouse gas levels are intricately related with temperature change and that temperature, precipitation, and storm patterns can change dramatically in very short periods of time"
The most prominent, and there are many others, is the collapse of the Mesopotamian Empire 4,200 years ago. The abrupt climate events that coincide exactly with the collapse of that civilization is the most remarkable event of the last 10,000 years of its type. The importance of this event, as with some others, is that it basically led to a shift in the moisture bearing winds and when this type of climate shift occurs, within a very short period of time, the civilization dies out.
Now, hunters/gatherers will simply move away. But, once you’ve built super structures around cities, you can’t move. We like to think that because we’ve built up our society and we can air condition and control the interior of our environments, that we are not susceptible to climate change, but in fact we are. Also, we tend to build our cities in the wrong place sometimes.
SC: Those locations might have been really good places for a community of hunter/gatherers, but building superstructures in Manhattan was probably not a really good idea for long-term sustainability.
PM: Right. The next major event is the collapse of the Mayan Empire, 900 AD, also for the same reason: the shift in the moisture-bearing winds. And then there was the collapse of the Norse colonies during the little ice age onset, 1400 AD, when temperatures didn’t drop that much, maybe a degree centigrade. That small decrease in temperature was enough to cool temperatures in the North Atlantic so that sea ice surrounded Greenland.
SC: So what in the ice core data that you have correlated to these major identifiable events can give us insights to where we might be at this moment?
PM: Depending on the melting of the Northern Hemisphere ice and changing temperature gradients, atmospheric circulation systems are going to shift, they are not going to have their normal pathways, so we should expect in some parts of the world more drought, or in other parts, more precipitation.
The other thing we know about these ACCE's is that some of them are associated with melting of ice, so the melting of the Greenland ice sheet is very important because it can add freshwater to the North Atlantic, altering the transport potential of heat carried by the ocean from North America to northern Europe.
I’d say that there is every reason to assume that if abrupt climate change happens as frequently in the past under conditions in which the earth's climate systems have not been perturbed artificially by the excessive release of carbon gases into the air by humans, it is very likely that we’ll get abrupt climate change in the future as a consequence of the enormous increase in level and rapidity of rise in greenhouse gases.
SC: You've just returned from Antarctica. You continue to regularly lead teams of scientists to Greenland and other locations and continue to extract ice cores. You’re there, you’re on the ice sheets; you’re seeing the melting first hand. Your teams are seeing the big holes in Greenland with the water draining out. You’re seeing all these things like the increasingly rapid movement of these glaciers breaking off and melting in the oceans. This is not just theoretical modeling, this is happening right now. Globally, we are well beyond the avoidance of the implications here.
PM: Well, I direct a research institute called The Climate Change Institute. Obviously, I believe in climate change and understand that it has happened in the past and I've studied abrupt climate change events. I’d rather not experience or have the planet experience an abrupt event, so I’m very, very concerned. I spend a lot of time giving public lectures on this topic. But I also don’t want to go around scaring people, because I feel that if you scare people, they will either go into denial or they will assume that nothing can be done. I prefer to offer a slightly different message.
SC: Information about global warming is everywhere: In the news, documentaries, and inexpensive books written for the general reader thoroughly explaining our situation. I think that we are already in denial, and we already are scared. For the same reasons that we’re not taught in our educational institutions to think in terms of complex systems, when large, dynamic systems like climate begin to have an impact on our lives, we don’t know how to negotiate the information and act accordingly. There’s an important distinction between using information to scare people, which serves no purpose at all, and presenting information to empower.
PM: I agree.
The message that I give people is two fold: In terms of the temperature rise, some argue that the climate models that have been developed through rigorous study of the data are just simple storytelling. But in fact, the models that were generated in the late 1970s, along with the later models that have shown the rise in CO2, the rise in sea level, the rise in temperature and all other data gathered, when we take a look at all of those models together, if anything, those models slightly underestimate where we are today. So that tells me that we should have quite a bit of faith in models.
And the other message, of course, is that it is within our control to regulate the levels of greenhouse gases. It isn’t necessarily the easiest thing to do and there are people that are concerned about their jobs and the cost. In my view, the situation is significant enough that the commitment to cleaning up our environment should be total. And, it shouldn’t be just greenhouse gases. It should be all of the pollutants we generate.
Greenhouse gases are raising global temperatures, therefore raising the likelihood of disease and climate calamities. But at the same time, the increased levels of things like toxic metals in the atmosphere, on land and in the ocean, are all impacting our health also and all these things ultimately impact our wealth too. The reward is more than just averting disaster.
This is a different kind of earth threatening problem. My own view is that this is a wakeup call and if we’re smart enough to take this wakeup call it could be an amazing opportunity. We are not going to be able to avoid the fact that we have to pay the mortgage for the rise in greenhouse gas levels; temperatures will rise. But we can improve both air and water quality and thereby ensure that the quality of our lives and our health is better by cleaning up air and water quality along with reducing greenhouse gas levels to assure that temperature rise will be minimized as much as possible.
I am a great believer in the fact that earth’s climate goes through cycles. But these cycles that I study and talk about in my book operate on many hundreds to tens of thousands and hundreds of thousands of years. I think it’s very important for us to realize that there is a lot of natural order to the climate system but we are now pushing very hard and very, very rapidly outside of that natural order. So, for anybody to assume this is just something that was going to happen anyway, there is absolutely no evidence whatsoever to support that kind of assumption.
By continuing to study ACCE's, we can get even greater insights into both the periodically occurring and the non-periodically abrupt climate change events that occur. If we could begin to predict ACCE's, especially in those regions that are most dramatically impacted, then we could do smart things in the future about those. Among the smart things, of course, is determining where agricultural regions should be.
Dr. Mayewski's research institute can be found at www.climatechange.umaine.edu/index.html and Dr. Mayewski’s book, The Ice Chronicles: The Quest to Understand Global Climate Change, is a highly recommended read.
What can we learn from earth’s preserved history?