On Thursday, Oct. 4 at 4:15 p.m. in Cole Cinema, the Department of Anthropology’s first Visiting Anthropologist Dr. Kit Wesler presented a lecture called “An Archaeologist’s Perspective on Climate Change.” The talk discussed the history of climate change in the archaeological record and the affect that humans may have on the natural cycles that the earth experiences. Dr. Wesler is a Professor of Archaeology and the director of the Mid-America Remote Sensing Center at Murray State University (MSU) in Kentucky.
The lecture began with an introduction from Adjunct Professor of Anthropology Sara Rivers-Cofield. Dr. Wesler was Rivers-Cofield’s professor and has remained her mentor for many years. “He is one of the few people in archaeology with knowledge in historical archaeology and pre-history,” she said. “His interests seem to have no bounds…he has a wide geographic and temporal range.” According to Rivers-Cofield, Dr. Wesler saved the department of archaeology that had gone downhill by combining it with the Geosciences Department. This way, the students could have access to the wide range of equipment and support they needed to help the department thrive.
After being introduced, Dr. Wesler took the podium and began to talk about the “topical subject” of climate change. He said that putting it into a long-term perspective is very difficult because the climate is changing constantly. The earth undergoes natural cycles that are embedded in each other, and archaeologists are only starting to understand what it means to human cultures.
Scientists know of several cycles that are topical to today’s discussions of climate change. The natural 100,000 year warming and cooling cycle affects the changes in glaciers across the globe and is crucial to the understanding of geology. The bottom of this cycle was approximately 18,000 years ago, so the earth is 18,000 years into the 50,000 year warming cycle. This made a huge difference in human pre-history because 1/3 or more of the North American continent was covered in ice, changing the shape of the world’s landmasses. This ice is what made it possible for the early humans to cross over Beringia to reach North America. When the ice retreated due to this cycle, the modern outlines began to take form and affect how humans distributed themselves across the continent.
There are likely two other cycles; one is called the hipsothermal eastern cycle that stretches over about 6,000 years and is currently 1,500 years unto the warming cycle and the other is a very short 70-year cycle. The glacial climate and hipsothermal eastern cycles are in the upswing of the warming periods so they are reinforcing each other, which is making the trend of the 70-year cycle higher.
There are several historic periods in human history in the Northern Hemisphere that have seen cultural changes that seem to coincide with the change in climate. The warmer periods see cultural expansion, like in the Roman Climatic Optimum that allowed the Roman armies to push north into Britain. The cooler periods see the cultural fragmentation, like in the Little Ice Age that brought about famine and disease in Europe. Dr. Wesler cautioned that one cannot attribute these cultural changes to climate change alone, but they are effective in observing “human action, interaction and reaction to climate changes.”
When studying these periods of climatic history, Dr. Wesler examined the Southern Hemisphere to see if it was a latitudinal pattern. He observed that there was cultural growth in the south while society was collapsing in the north and it has “profound impacts on how more complex societies organize themselves.”
In the last 40 years, all of the cycles that Dr. Wesler identified have been reinforcing each other to provide data to support the trend of warming. However, he did not say that these cycles eliminated the human responsibility in global climate change. One gallon of gasoline emits 25 pounds of carbon dioxide into the atmosphere and to cancel out all of the carbon emissions by the United States residential areas, 11 million acres of fully grown walnut trees would have to be planted. Dr. Wesler said that the trends of warming are irrevocably on the rise and instead of blaming each other, humans need to begin to prepare. Humans have to stop contributing to global warming, but the temperature will continue to rise regardless. He said, “We know what’s happening. We need to start recognizing that past societies that adapted did okay.”
Dr. Wesler proposed several adaptations that the world could begin to implement today to prepare for the global rise in temperature. Building designs should be modified to facilitate cooling. There should be an overhaul of dams, flood protection systems, and ancient sewage systems to prepare for the increase in flooding in the future. Hydro-electric power plants must adapt to a lower flow. The rise in sea level will change coastal infrastructure. Farmers must adjust their land management and develop new cropping practices and growing zones. Humans must prepare for new disease vectors and the movement of marine species. Politicians, he said, need to begin to worry about the long-term perspective, not just what will win them the next election.
The main poins Wesler lef the audience with on the topic of climate change was that the world needs to accept that climate change is happening and begin to adapt and plan for the rise in temperature. “This is what archaeology is all about,” he said. “Long-term, global perspective.” Archaeology puts modern problems into a longer frame of mind and ensures that patterns are better understood in a long term global view. “Every project gives us a piece of this puzzle. You’re the generation that will prove me right or wrong, but I’m right,” he ended with a laugh.
Dr. Wesler answered the many questions from the students and faculty and positively received. “I found Dr. Wesler’s perspective on global climate change to be rather different from many others and very interesting,” said sophomore Danielle Lafferty. Wesler earned his Ph.D. and M.A. at the University of North Carolina and his Bachelors degree at Washington University. He is currently working on two books.