On Friday, Pulitzer Prize-winning author and Class of 1946 Environmental Fellow-in-Residence Elizabeth Kolbert spoke about climate change and other topics from her recent book, The Sixth Extinction. Her talk was part of a spring lecture series hosted by the College chapter of Sigma Xi, a national society devoted to honoring and promoting scientific research.
The “sixth extinction,” Kolbert explained, highlights humans as the next species in line for a large population drop. Five other extinctions have occurred throughout history; the first took place around 440 million years ago. The third extinction was notably the worst and took place about 250 million years ago, while the fifth and most recent extinction was that of the dinosaurs, mosasaurs and pterosaurs and took place about 65 million years ago.
Kolbert pointed out that there are several ways in which humans affect and harm the world. She focused on three: atmospheric change, ocean change and geographic distribution change. Atmospheric carbon dioxide levels are currently at over 400 parts per million. She described witnessing the procedure of taking ice cores, lengthy cylinders of ice that are drilled out of an ice sheet and used to reconstruct a climatic record over a long period of time. These ice cores are evidence of increasing temperatures. “We’ve probably reached the point where we’re never going below 400 parts per million again, certainly not in the lifetime of anyone in this room,” Kolbert said. “We’re not going to do that until we stop emitting carbon dioxide, which, once again as you know, we show no signs of doing.”
The lecture continued with a discussion of ocean acidification, a phenomenon that results from increasing levels of carbon dioxide, a third of which is absorbed by the ocean. The resulting rise in ocean acidity causes problems for marine life, particularly for shell-dependent organisms like shellfish, sea urchins and coral. Kolbert described swimming off the coast of Naples where underwater vents spew large amounts of carbon dioxide each minute and increase acidity in the surrounding waters. “If you keep on emitting carbon dioxide at our current record pace, we will get to a pH of 7.8 ocean-wide by the end of the century. That is potentially the kind of ocean we’re looking at,” Kolbert said.
The lecture concluded with a description of the dangers of invasive species, the destruction of animal homes and the recent and ongoing extinction of several bird species. For example, Kolbert revealed that there are only 126 Kakapo, which reside in New Zealand, left in the world. She also highlighted how seemingly unnatural current events are a result of human actions. “By bringing together all these species that have evolved on different continents, we are in effect bringing the continents back together again. We are creating a new Pangaea.”
“I would tell you what we can and should do about all of this. However, I do not have that ending,” Kolbert said. Instead, she ended her talk with an anecdote about Kanoi, a rare crow she once befriended. This bird, with its capacity to imitate human speech, uttered two words to her: “I know.” This phrase, she said, resonated with her; the bird’s seeming understanding of the events of the world made her feel less alone. “Ultimately, I think that we as a species actually end up having a lot in common with these birds. I’m ending on Kanoi and [the idea] that we are a rather confused species as well.”
Following her talk, Kolbert answered questions for a brief period. She noted a trend in climate change skepticism and explained how the current patterns of extreme weather has resulted in a rise in climate change belief. She hopes that more people will hold firm in their climate change convictions and in the fight against global warming, regardless of the current weather. She also stated that she has no immediate plans for further work or research in the near future.