[EMAIL PROTECTED] wrote: > Original Message: > ----------------- > From: Kevin B. O'Brien [EMAIL PROTECTED] > Date: Tue, 29 Apr 2008 15:56:38 -0400 > To: brin-l@mccmedia.com > Subject: Re: culling the species > > > > >> If not, why do you think that the present level of population is >> unsustainable? In the US, at least, farms are much more productive and >> > are > >> farmed in a far more sustainable manner than they were 50-100 years ago. >> Indeed, my father-in-law's old farm has been gaining topsoil over the last >> decade or so as a result of improvements in soil management. >> >> That is good, but you yourself have made very persuasive arguments with >> respect to global warming that there is no feasible way to cut back on >> carbon emissions per capita. >> > > What I said was that, with present technologies, we shouldn't expect China > to do that. So the world warms, and the best farming zones shift north. > Canada and Siberia will gain, others will lose. On the whole, higher > rainfall is exspected. Only China? You don't expect anything from India, or the rest of the world? I am fairly certain that everyone in the world want to have the same standard of living that we in the wealthy west have. A quick-and-dirty estimate is that this will require about a 6x increase in output per capita. And that output will come with some load of pollution, energy use, carbon emissions, etc. I don't think you can be quite so Panglossian with these trend lines. > Fishing suffers from the tragedy of the commons. Whale's were overhunted a > century ago, yet the green revolution of the '60s massively cut into world > hunger. I recall when India needed massive imports of US food just to keep > its people alive. Until the latest stupidity with regard to biofuels, food > shortages were almost always caused by men with guns who kept food away > from starving people and by real studid government policies. > I don't quite see why applying the label "Tragedy of the Commons" voids the main point here. For there to be healthy fisheries there needs to be a balance between the rate of reproduction and the rate of withdrawal, and that has clearly been violated here, with fisheries collapsing just about everywhere you look. And this is a fairly recent phenomenon. I think the correlation to population pressure is pretty robust. >> For example, the so-called bread basket of the U.S. used to be called >> the great desert. >> > > The Great Desert was in the SW. > see: http://en.wikipedia.org/wiki/Great_American_Desert > >> What changed that was to drilling of wells to tap the >> Oglala aquifer, turning places like Kansas and Nebraska into prime farm >> land. >> > > My experience with farming is that corn and soybean farming relies little > on irrigation. Those problems do exist, but more in the arid SW regions. > If you look at places like Iowa and Illinois and Minn., 3 out of the 4 big > corn producers, you see little irrigation. The environmentalists keep > yelling non-sustainable, but these areas are not depleting reservoirs in > order to farm. > I'm pretty sure I never brought up Iowa, Illinois, or Minnesota. I brought up the depeltion of the Oglala Aquifer, and you can find more on this at http://en.wikipedia.org/wiki/Ogallala_Aquifer. Note that it is a deposit of ground water laid down 2-6 million years ago, and is begin depleted at a rate equal to the flow of 18 Colorado Rivers every year.
"There are a number of Great Plains areas where large-scale irrigation developments are important. Perhaps the most noteworthy of these is on the High Plains from Colorado and Nebraska to Texas. The area is underlain by the Oglala aquifer, a vast underground geologic reservoir under 250,000 square kilometers of the area that contains an estimated 2 billion acre-feet of water. (An acre-foot is the volume of irrigation water that covers 0.4 hectares to a depth of 0.3 meters.) This is "fossil" water, much of it deposited more than a million years ago. About a quarter of the aquifer's area is irrigated, almost entirely with Oglala water. The High Plains is a major agricultural region, providing, for example, two-fifths of America's sorghum, one-sixth of its wheat, and one-quarter of its cotton. Irrigated lands here produce 45 percent more wheat, 70 percent more sorghum, and 135 percent more cotton than neighboring nonirrigated areas. Groundwater withdrawals have more than tripled since 1950, to more than 20 million acre-feet annually." Source: http://usinfo.state.gov/products/pubs/geography/geog11.htm Now, if it runs from Colorado and Nebraska to Texas, I'm pretty sure it runs through Kansas to get there. Or you can consult the map at Wikipedia to confirm that it does indeed underly Kansas as well as the other states. > Places like OK and the TX panhandle may have problems, but that's more > ranching country. > > > >> The problem is that we are essentially mining this resource in a >> non-renewable manner. The water in this aquifer was collected over >> millions of years, and we are using it up in decades. When it is gone, >> Kansas and Nebraska will return to being desert, and what happens to >> food supplies then? >> > > > > If you look at these rainfall maps, you will see that Kansas and Nebraska > get far too much rain to be remotely consistent with being deserts. Far > West Kansas is a bit dry, under 20 inches/year, but east Kansas is in the > 36 to 40+ range. Eyeball averages give about 25 inches rain/year. That > should be plenty for sustaining crops. Nebraska's a bit dryer, averaging > about 22 inches/year. That's not a desert. > > http://www.wrcc.dri.edu/precip.html > The term was applied to this area historically. But it does some justice to the idea that without irrigation these areas would not be major agricultural producers. The fact on the ground is that agriculture in these places *does* rely on irrigation right now. Maybe all of these farmers are just being foolish and investing money in irrigation for no good reason and ignoring all of the rainfall that they are getting for free. >> If you look globally, water supplies are strained just about everywhere. >> > > Clean, safe water supplies are. But water is usually available, we just > don't spend the modest amount of money to make it safe for undeveloped > countries. It is possible that we will have to improve our use of water, > and the cost thereof to handle farming. But, we now have or are on the > edge of having design capacities for better drought resistent crops. If we > don't do stupid things like divert 40% of corn production to ethanol, then > food shouldn't be a problem. > For the U.S. it is not overall a critical problem yet, though in certain areas it is becoming more of a problem. I note that California is casting covetous eyes at the Great Lakes, for instance. As a resident of Michigan, my first reaction is that anyone stupid enough to move to the desert deserves their problems without my help. But I suspect it won't exactly play out that way. And I agree that for the U.S. the money to be spend is relatively a "modest sum". But take a look at what happens when you try to increase output by 6x. Water consumption per capita goes way up, not just for agricultural and home use, but for industrial use, which has the side-effect of generally polluting the water. So the real question is whether the water supply is sufficient to cover a global population of over 6 billion (and still growing) producing approximately 6x the current level of global output. If you are looking at sustainability, that is the real test. And I don't think water supplies can stretch that far, frankly. >> This is one example of a bottleneck factor. To me it seems obvious that >> the present level of population is higher than the environment can >> support sustainably in the long-term. >> > > > OK, let's look at an area with >2x the average population density of the > world: Western Europe. Where's the environmental catastrophy there? > Indeed, Europe can afford to supplement very inefficient agriculture > policies (with about half of the EU's budget) and still produce enough food. > OK, let's look at Europe. The environmental problems that they are having are modest at this point. And they do have a high population density. Europe has a pretty benign climate, good soils, and an abundance of water. Two of those factors depend critically on global climate. The benign climate and high levels of rainfall are dependent on the current global climate, in particular the Gulf Stream. And global climate change is already causing alterations there. Europe is getting drier now, and scientists are predicting increased environmental stress (including reduced crops) from that. If the Gulf Stream were to either shut off or significantly shift, both of which are considered very possible as a result of global climate change, there is no doubt that a very significant environmental catastrophe in Europe would result. The point of my argument, to restate it, as that numerous indicators are pointing to the fact the human populations have risen beyond what can be sustained within our environment, and I think that is still a valid point. I could also have mentioned extinctions/loss of biodiversity and the loss of habitat, which are also clearly caused by population pressure from humans. Some of these can be overcome, to a degree, by the clever use of technology, but that must do so at a level of output that provides a standard of living to all humans equal to those enjoyed by the West to be viable over the long-term. And even that probably understates the task, since I don't see any sign right now that people in the West are willing to settle for stagnating standards of living. Regards, -- Kevin B. O'Brien TANSTAAFL [EMAIL PROTECTED] Linux User #333216 "Few people think more than two or three times a year; I have made an international reputation for myself by thinking once or twice a week." -- George Bernard Shaw _______________________________________________ http://www.mccmedia.com/mailman/listinfo/brin-l
