As is the case with most things that are important, we as a society have done a very bad job of developing an effective conversation about Global Warming. The vast majority of electronic and real ink that I see spent on the discussion of Global Warming (outside of the peer reviewed literature) is not even about climate or climate change. Rather, it is about talking about climate change, the politics of climate change, critique of the rhetoric about climate change, clarification, obfuscation, complaining, accusing, yelling or belly-aching, and the occasional threat of violence. And today, dear reader, I’d like to give you some more of that! (Well, some of it. There will be no threats!)
I was having a conversation the other day with a colleague, and we talked about a lot of different things mainly having to do with science education. He is a fellow scientist, there is some overlap in our training, and we are both members of the same secret scientific society which, of course, I can’t tell you about. During this conversation he was moved, appropriately, to warn me that his view of Global Warming might be different than mine; he does not see global warming as the number one problem facing species diversity and survival. Since he is one of the world’s experts on global insults to species diversity, I took heed.
We continued our conversation and I quickly realized that we had pretty much the same view. Mainly, the importance of Global Warming vis-a-vis species diversity and survival, relative to other human-caused insults to the planet, is unknown. The power in my Blog Cave is out at the moment, so I can’t look this up, but my friend Emily Cassidy recently noted that some large number … over half? … of the terrain not otherwise covered with ice (as in polar caps) or water (as in lakes, and of course, the oceans) on this planet is in use for agriculture. A big chunk of that is range land (because that takes up so much space) but a lot of it is monoculture.
The scale of human modification of the land for agriculture is astonishing. On a recent trip to the southwestern part of Minnesota, I saw field after field after field of corn and nothing but corn other than the occasional housing development or swamp. Then we got to our destination, a prairie restoration project, and there was this one plot, the edges of which could be easily seen from any point on that plot. The plot was heavily invaded by invasive species, and there on this plot were dozens of plants of a certain prairie clover which was busily going extinct.
Regionally, the nighttime humidity is measurably higher than it has been known to be in the past because of all this corn, which lets a lot of water out of its cells during the dark hours, relative to the native grasses.
So on this patch down in southwestern Minnesota we have climate change in the form of shifted humidity, nearly complete habitat destruction because of agriculture, and invasive plants and animals running around. There is also global warming. There are warmer winters, more frequent severe storms and flooding, and much higher summer temperatures.
All these things matter. Which maters most? Does it matter which matters most? Are we going to do something differently if we find out that the list of insults to our plant, in order of importance, is 1) invasive plants; 2) anthropogenic global warming; 3) habitat loss vs 1) anthropogenic global waraming; 2) habitat loss; 3) invasive plants?
No, and there are several reasons. First, there are things we can do and things we can’t do, depending on who we are. On that visit I spoke with some of the people in charge of saving that nearly extinct clover plant. They saw the situation as pretty hopeless, but they were trying, and they probably could not have put their energy usefully into something else. You could, if you like, go down there and demand that they stop trying to save the clover and instead start working on a windmill, or start raising money to buy back some farmland and restore it to native prairie. But it will not work. Wild plant lovers will spend their time with wild plants, other conservationists will work on the habitat loss, and if the deniers would let us get on with it, there are things we can do in the State Legislature to help with the AGW problem.
The other “problem” with “Global Warming” is the focus on “Warming” as though the big problem was simply ambient temperature. If that was true all we would need to is wear a lighter jacket in the spring and do some land management magic to let the Minnesota Moose, who can’t live here any more because of the shifting habitats, migrate north up to Canada. But the problem is different than that. There are three major problems with AGW that are not as simple as things getting warmer: Redistribution of energy, redistribution of the form of water, and ocean acidification.
The redistribution of energy is related to the changes in water (which I’ll note in a moment) and is, of course, related to the warming itself. Habitats are determined by patterns of weather, and climate is the long term manifestation of weather phenomena. But what is weather? Mainly, weather is what happens when excess solar heat that builds up along the equator, on land, in the air over the land, at sea, and in the air over the sea, moves towards the poles mainly as masses of moving air or water. Winds are driven by this differential in heat, and ocean currents are driven by heat differential as well as the winds. (This is a simplification of course.) It gets pretty darn complicated when you add in continents and mountains and stuff, and of course the earth’s spin is a factor, and the tilt of the earth causing a seasonal effect, etc. etc. But the main thing that is going on is the movement of solar energy from equatorial regions towards the poles. With a heated up atmosphere the basic pattern may be the same but the details may be quite different. Or, the basic pattern of this process may change dramatically. We don’t know the full range of possible changes, but it does appear that some regions become much drier at the same time that the atmosphere becomes much wetter. So, wet regions may get wetter, and dry to medium dry regions get more severe storms, so they don’t really get wetter (storm waters tend to run off) but they do get messier.
So, on my visit to southwestern Minnesota, had I stood there long enough, I would have probably been more likely to be hit by a severe thunder storm or even a tornado. Hey, wait a minute … as I recall we WERE hit by a severe thunderstorm on that trip. See?!?!?
The redistribution of forms of water may be more important with respect to humans. During any given year, water on Earth is distributed in several different forms on average. There is ocean water, glacial water, winter snows and ice, water frozen in the permafrost, water in fresh water bodies or groundwater, and water vapor in the air. Where the water is and in what form feeds back to climate conditions (glaciers cool things down by reflecting away sunlight, for instance). One of the outcomes of long term AGW is the movement of lots of frozen water into the oceans. If enough of this happens, a significant proportion of the earth’s human population will have to move away from the coast lines. Also, the ecology of coastlines will change. Long term low energy estuaries will be opened up to the sea if sea level rise is fast enough, and although they will reform later when sea level stabilizes, there is evidence that certain kinds of habitats will become very rare.
To me, Ocean Acidification is the biggest unknown but at the same time possibly the biggest problems. Adding CO2 to the global system increases CO2 in the sea water, and this increases acidity. Under these conditions, organisms that rely on a lower acidity to build their “skeletons” may simply become very rare or go extinct. These organisms, at the moment, are responsible for making some of our Oxygen out of CO2, and they are at the base of the oceanic food chain. Breathing and eating are important. These activities may become disrupted because of Carbon being added to the system.
Speaking of carbon, consider the costs of separating fossil carbon from its molecular crypts in oil, coal, and gas as part of our use of energy. The other day I cleaned the deck of my front porch. It was covered with a layer of black soot. Thank you very much Big Giant Coal Burning Plant that lives upwind from us, and thank you very much to all the trucks and cars and everything else. But at least we don’t work at a coal mine; but others do, and suffer for it. This fossil carbon, with its energy-storing bonds that we break to make fire, is unevenly distributed across the planet. So, being humans, we go to war over it now and then, sometimes just economic war, often real fighting wars. The process of getting this carbon out of the ground and into your lungs or on you porch is also one of the most important money making operations on the planet. The rich are getting richer, the poor are getting soot. Well, everybody gets the soot, or the global warming, or the ocean acidification, but the rich get to enjoy themselves a bit more on this toboggan slide we’re on.
The thing we call “Global Warming” is real, and it is caused by humans, and it matters. But it does not exist in isolation, the “Warming” part of it is important but not the only part that matters, and it is not our only problem. Some people think global warming either irrelevant or good, because they don’t mind a bit more warm weather. But that is not what global warming is about. Species diversity is probably threatened more by agriculture, via habitat loss, and possibly by invasive species, than by global warming. But global warming is not chopped liver. All these things are on the list of critically important problems. The only way to solve these problems is with the intelligent and effective implementation of well formed science policy on the local, national, and international levels, with that policy derived from good science supported by a well informed citizenry.
So, how do we do that?