DATE: July 19, 2018
SNIP: A recently released study brought sobering news about the future effects of climate change, predicting they could be twice as bad as current models have projected under a “business-as-usual” scenario — and then some.
From the study: “Comparison of palaeo observations with climate model results suggests that, due to the lack of certain feedback processes, model-based climate projections may underestimate long-term warming in response to future radiative forcing by as much as a factor of two, and thus may also underestimate centennial-to-millennial-scale sea-level rise.”
Two of the study’s co-authors, Katrin Meissner, director of the University of New South Wales Climate Change Research Centre, and Alan C. Mix, distinguished professor of earth, ocean, and atmospheric sciences at Oregon State University, recently spoke with Nexus Media about the study, which was conducted by an international team of researchers from 17 countries.
A snippet from the interview:
“It is reasonably well known that in the Pliocene time interval, roughly 2–5 million years ago, CO2 was a bit higher than today. The exact cause isn’t known, but it came from some geologic reservoirs where CO2 is locked up today. These reservoirs are things like organic matter in soil and in sediments under the ocean. It isn’t a lot of carbon in every square meter, or square foot, but there is a huge area, so it adds up. Carbon is also stored today in permafrost, and in the deep ocean. The fact that the Pliocene was both a bit warmer than today and had a bit more CO2 in the atmosphere is important, because it shows that warmth, however it is triggered, can become self-sustaining by letting some of that locked-up carbon out into the atmosphere. In other words, the climate system isn’t “self-correcting.” It doesn’t automatically return to a state that looks like the one humans enjoyed as they built their modern civilizations. We used to think that. A few decades ago, there was a popular idea called “Gaia,” the Earth Goddess, which basically thought that the living Earth was self-correcting to stay within a narrow environmental range suitable for life. For the most part, those ideas have been abandoned. We now know the Earth has experienced some pretty large climate swings, and they likely involve release and uptake of CO2. So maybe life helps to stabilize climate on a very large scale, a Gaian idea, but on the scale that matters to us here and now, we know the system is sensitive to change because it has changed. So if Gaia is a Goddess, she certainly is fickle.”
“We are changing climate much more, and much faster, and on a much larger scale, than anything humanity experienced in its early history. I’m discounting the Neanderthals who lived in southern Europe during the ice ages — I don’t want to be a cave man and I don’t think we want to go there. Although we have modern technology that can help us, we also have nearly eight billion people on the planet, and we are already seeing daily crises with refugees. So if climate change makes a region of the planet uninhabitable, those people can’t just pick up and go somewhere else. There is no place to go on an overpopulated planet. What will we do when we see hordes of climate refugees fleeing rising sea levels flooding their cities, or crop failure from heat stress, or insufficient water? Who is responsible? Who will take them? The issue of surviving climate changes in the past is a red herring that says nothing about today.”
It is well worth reading the whole interview.