The most surprising idea that I encountered in the videos came in the discussion with Professor Dan Kammen regarding the deep ocean conveyer belt and the fact that climate change could cause it to stop circulation in the ocean. Not only would this lead to an ice age, similar to the one we saw in Day After Tomorrow (which I didn’t think was possible in reality and was more of a Hollywood creation), but it would have significant adverse effects on ocean wildlife which rely on ocean circulation, and possibly lead to large bodies of stagnant water that could serve as incubation spaces for all sorts of bacteria and other microorganisms. Although we think of climate change as mostly causing rising sea levels and extreme weather, this potential consequence seems to me to be magnitudes more serious, and I was wondering if life on earth and in the seas (as we know it) could even survive without ocean currents. Although Professor Kammen mentioned that this would not happen in the course of days, as portrayed in the movie, I wasn’t sure if the realistic timespan was years, decades, or even centuries? And once the process of stopping the conveyer belt began, would it be too late for humans to reverse it?
Yes, reducing UNCERTAINTY is urgent—in so many areas related to Climate Change forecasting. We know it’s “bad,” but how bad, and in which areas, is what we need to know to act most effectively.
I agree that the way climate change threatens the deep ocean conveyer belt is extremely threatening. However, due to the nature of these models, it is extremely difficult (as Kammen mentions) to determine exactly how much warming would lead to this outcome. It's possible that climate change would not affect this pattern, while it's also possible that we could see dramatic temperature changes in Europe as a result in just a few decades. Quantifying the probabilities of each outcome is very difficult as well. Either way, the risk is so high that it demands immediate action to reduce emissions.