Introduction

The NCAA tournament, which currently just went beyond the sweet 16 into the Elite Eight shows we're in the home stretch of the NCAA tournament. We're also in the home stretch of this course. It's the latter half of the second half. We've talked about the basic science behind climate and climate change. We've talked about the model projections under various possible scenarios of future carbon emissions, and we've talked about the potential impacts of those emissions, so now we're going to talk about the issue of what to do about this problem. We will consider a few different possibilities. Right now, we've started talking about adaptation, what adaptive measures can we take to adapt to the changes that are coming and in fact we are already committed to some amount of future climate change no matter what we do with our emissions so some degree of adaptation will be necessary. And so we've been talking about adaptive measures we can make in the area of water supply agriculture dealing with sea level rise and other impacts of climate change, but beyond adaptation what can we do to deal with the problem of climate change?

What can we do to deal with the problem of climate change? Well, we can try to mitigate it, and there are actually two different approaches that have been widely discussed in recent years. One of them that's quite controversial is so-called geoengineering, so one possibility is we try to engineer our way out of climate change by perturbing the climate system in other ways to offset the warming due to increasing greenhouse gas concentrations. So we'll talk about that concept of geoengineering and what it might be able to accomplish and what the potential pitfalls are. Finally, if we don't consider geoengineering as a viable solution to the problem, that leaves us with only one solution to stemming the problem at its source which is the increasing greenhouse gas concentrations themselves, and so our final lesson of the course will be talking about mitigating greenhouse emissions. Carbon emissions cross every sector of society, every sector of modern civilization from energy supplied at transportation, to agriculture, to buildings, construction of buildings, to waste management. So clearly if we're going to decrease carbon emissions we need to consider potential actions across all sectors of our modern economy and modern civilization, and so we'll talk about those details, and we'll see if it indeed is possible to decrease emissions in a way that is consistent with stabilizing greenhouse gas concentrations at a level below that where we will start to see some of the more dangerous impacts that we've talked about in this course. And so it isn't coincidental that the titlist course is from meteorology to mitigation. We started with the basic science, the basic meteorology and atmospheric science of climate change, and now as we finish up the course we're going to take the problem all the way through the issue of solutions, or what we do about the problem.