The Definite Article

The "earth is getting warmer" part is a bit simplistic to me. The earth's climate is changing, perhaps becoming more chaotic, with some areas becoming warmer and some colder and some with more variable weather (even that's too simplistic). On the whole, more variable weather may be more devastating than simply warmer weather as it makes it difficult for plants and animals to adapt. We can't predict weather out a month, let alone 50 years, so I have to take climate prediction models with a grain of sand. Things are changing, and probably not for the better for everyone as you said, but no one knows what's going to happen.

The biomass in the ocean is a big concern of mine too. The overfishing of many stocks may lead to a drastic collapse of the undersea ecosystem, with land ecosystems not far behind. I think we should be doing more to promote the growth of algae and other undersea life through peppering the seas with iron ore and sinking more ships. I think there are many areas of the sea that are barren in terms of life currently supported and just a little help.

Planting trees is a good idea, but we to do more, like resurrect old forests in places that are now desert. A forest isn't just a bunch of trees. It's a giant living thing with thousands of species of plants and animals interdependent on each other for survival. There's been some success in places along the Mediterranean where desert is being reclaimed by man-planted forest-ecosystems that used to be there thousands of years ago. The Gobi, the Sahara, and the entire Middle East used to be fertile land before mankind over-farmed, over-hunted, and built over it. We need to turn that all back into forest and keep the rest of our forests from being turned into more desert.

On the bright side, global warming probably won't wipe mankind out. Global food supply collapse from overproduction coupled with population growth will likely do us in long before global warming has a chance.

I take issue with the assertion that mankind has contributed to creating deserts in any period of time that is not the last 150 years. It's worth remembering that about a millennium ago, global warming shepherded vast population increases in Europe as a result of increased farm efficiency (not hurt by increasingly effective agricultural practices).

However, I am less worried about overfishing causing a collapse in ocean environments because what is the source of the ocean as an oxygen sink is not threatened. By far the vast majority of sea life lives within 100 miles of land. this is due to erosion creating a mineral rich environment due to wave action and terrestrial runoff. A rapid and available solution to emission problems lies in the construction of massive offshore algae farms, where there is little or no life, already.(c 2007, Mendon Dornbrook:) Furthermore, the ocean undergoes a much more rapid reintegration of detritus into unavailable substances.

I think we are the stewards of the planet and we don't quite think of it as a whole yet. Kind of the thinking line that we are all related and should not kill each other kind of thinking is where we need to be united in the way we regard the environment we live in and the climate which affects us etc,etc. The planet has an engine which provides much of its energy systems outputs and associations.
Can we put a crimp in how that functions? I doubt it. However, we may be able to effect better end results with how we utilize such energy systems for our well being in conjunction with the planet.
I studied geology many years ago and we did a basic study which showed that if we stopped polluting for a month the whole planet would make itself pristine through its amazing filtration systems on the surface. If that length of time has increased, I cannot tell you. I do know that histroically the ice shields tell us that the ozone layer depletes on its own in fairly regular cycles.

Just one piece of evidence for desertification:

An analysis of seed collections of rodents shows the gradual elimination of trees in Egypt corresponding to the exponential growth in population. As cities grew, larger and larger areas needed to be cleared of trees for food, fuel, building material, etc. Egypt was a lush fertile country during the time of the pharaohs and was turned to desert relatively quickly.

A similar story befell many other civilizations. In fact, the Gobi, the Sahara, and the middle east are all right where some of the longest running civilizations have been present. The Chinese have been abusing their environment for several thousand years; why would a desert only form in the last 150? And how did the Egyptian empire (among many others) form and last so long in the desert? What the heck did they eat while they built the pyramids? Sandwiches? Heh heh. Couldn't resist that one.

Human activity is, at best, a proximal cause of desertification. To say that human activity increased desertification significantly is similar to suggesting that human activity made the Ural steppes rich. What is true is that Earth has been emerging from an ice age for the last 10,000 years. 4-6,000 of which mankind has been actively engaging in agriculture and other “civilized” practices. 10,000 years ago, deserts as we know them did not exist.

Deserts are formed based on water movement patterns. In tropical regions, hot moist air rises quickly to higher altitudes where it becomes cooler and precipitates, creating the tropics. When this air moves further away from the tropics, it is relatively warmer than the air below it, creating a stagnation effect, where the hot dry air coming off of a heavily precipitated tropic forces down any cooler moister air that is being formed via evaporation at these new regions (approximately 30 degrees North and South), stopping precipitation from occurring because the air closer to land that has a higher water vapor content, remains soluble and warm due to its proximity to land. As the planet has become increasingly warmer of the millennia, these regions have grown from almost nothing to vast desert tracts. Practices of over-farming may have ruined the soil, but planetary wind patterns created the desert. The effect of rising global temperatures, throughout history, is clearly present in the great cultures, while some cultures were reaping the benefits of increased temperatures, others were held back by increasing equatorial desertification and slowly warming northern regions. This was true for the Greeks and the Romans whose empires flourished as temperatures in at their latitude rose, increasing crop yields. Northern Europe was not much of a problem for Roman conquerors because the population supported by northern agriculture was much smaller than that of southern Europe. When northern Europe began to warm and agrarian technology advanced, the population of northern Europe grew to a point that it was impossible for Rome to contain it. At our present rate, it is likely that southern Europe will undergo desertification in the next hundred or so years, as desert-like precipitation patterns continue to expand.

I say the last 150 years or so, though I could point back to 1794 when James Watt and Mathew Boulton formed Boulton and Watt to begin selling steam engines. In the last several hundred years, mankind has made an unprecedented contribution to the increase in world-wide temperatures, thereby influencing the rate at which deserts on earth have grown. In other words, it’s fairly ridiculous to suggest that mankind had a significant impact on global temperatures prior to the invention of combustion engines.

You're a bright kid. And well-read. But you're not the only one who's bright or well-read.

The archaeological record clearly shows man's destructive effect on the environment. Wherever mankind went, we burned forest to make room for pastures. We over-farmed until the nutrients were gone. We Cut down trees to make houses. Without trees, rain washed the soil into the water. With no soil and no undergrowth, there was no way for mother earth to rebuild the lost ecosystem. Yeah, the wind had its part, but we got the ball rolling.

Look at Easter Island, quite possibly the worst anthropogenic ecological collapse of all time. The islands supported over 200,000 people at its height. And after they cut down and exterminated all 17 species of trees on the island (not to mention most of the wildlife), the population collapsed down to 2,000 practically overnight. Now it's desolate. Those islands went through millions of years of climate change without collapse. Man destroyed it in a few hundred years. And we're still doing the same thing, now on a global scale.

Hey Josh, I'm not denying deforestation's effect on the environment. I am arguing that it is a proximal and minimal cause in the overarching scheme of desertification. However, it has come to a point that deforestation is having a meaningful influence on wind patterns (see the last 150 years;).

By saying that deforestation is a minimal cause of desertification then you are in fact denying the effects. There is no greater cause of desertification on the last 10,000 years than anthropogenic deforestation.

The 8,000 mile wide swath of desert from northern Africa to the Gobi formed almost entirely in the last 10,000 years, as you yourself pointed out, roughly in parallel to man's growth in that area. Animal husbandry, agriculture, and permanent settlements all appeared in the "fertile" crescent roughly 10,000 years ago. It should be noted, that mankind took up these practices because as hunters they had wiped out most of the game in these areas. They had little choice but to give up the chase and raise goats.

It should also be noted, that the planet has gone through countless ice ages without having an 8,000 mile wide desert form. It's also been a lot hotter in the past with plenty of rain forests alive and well in the hottest parts. It is no coincidence that the desert happened to form exactly at a time when man was cutting down and burning all the forests.

It should also be noted that in the areas that have not been heavily populated, there are no deserts. Panama had no civilization to devastate it. Mexico did. The Aztec empire deforested its domain with as much fervor as the Egyptians, and now there is desert. Argentina has its deserts, mostly in areas the Incas once ruled. The American Southwest was similarly deforested by native Americans, and now it is desert.

Greenland was once rich in soil. The Vikings landed and cut down forests and planted crops as they had in Europe, but the soil in Greenland replaced itself from volcanic ash (which pretty much means not at all on our timescale). Pretty soon, the wind and rain had washed 10 or 20 feet of soil away. Wind and rain had their part, but again it was man who destroyed it. The Viking colony on Greenland perished very quickly, down to the last man. Iceland was almost as bad, but they enacted conservation measures to ensure their resources were sustainable, the only country today that can say that.

Back to my first argument about fishing stocks. We've severely depleted many species of fish over the years. Cod is all but a memory now. But cod isn't just a type of fish. It's a node in a vast network of undersea predators and prey. What effect will removing one node have on the fish, whales, and shark that prey on it? And what of the fish on which it preyed? We don't know for sure the exact effects of each node's removal, but we do know it can drastically effect the network. And we know all it takes is for one crucial fish that eats only other kind of fish to be wiped out to have a devastating ripple effects throughout the rest of the network.

Whales are almost gone, and most species are well below the minimum population to maintain genetic diversity. Many of the fish you find on your dining room table are getting harder and harder to find. Removing one crucial node is bad enough, but removing dozens or hundreds will surely be disastrous.

We've been similarly decimating land ecosystems. When native Americans landed in Alaska, it took only about 300 years to get down to the Land of Fire. In that time, they wiped out 76% of all land animals weighing 100 pounds or more in North America, everything from giant horses to giant sloths. Everywhere were man went, huge numbers of plants and animals went extinct practically overnight. It's easy to think of the woolly mammoth as an outdated and obsolete animal, extinct because its time had come, but the truth is it was a modern mammal living in a modern climate wiped out by modern man.

With an expanding population, and a shrinking food supply, it's only a matter of time before we see a massive ecosystem collapse. It's basically what we're seeing in Africa today. Too many people, and no way to sustain all of them. Malthus was right.

Besides Iceland, there is only one other society that used its resources in a sustainable manner. It was a small island in the south Pacific, whose name eludes me (I'd look it up, but all of my books are packed up already for the move). They used Onanism to keep the population at a stable level, and abortion and infanticide when that failed. They lived on 1/3 of the island, the other 2/3 reserved for when food was low. Early on, they realized their pigs were rooting through and destroying vital plant life, so they made the tough decision to kill all the pigs. When you compare how they managed their population and how they took care of their environment to what the rest of us are doing, it's not hard to see we're in for some hard times.

The temperature can go up or go down, but it won't make much difference when we're out of food.

I hate to beat a dead horse, but one more whack couldn't hurt.

Since you are saying that deforestation (and over-farming) did not cause deserts, or at best was a minimal cause, then you should be able to find a modern desert where large-scale deforestation did not occur in the past. Likewise, you should be able to point to areas where large-scale deforestation occurred but did not turn to desert. Mind you, my point is this takes a few hundred years in most climates, so forests cut down last year don't count. An instance of either one or both of these should be sufficient to prove your case.

Since we are still kicking this horse, I'll put in my two cents worth. I think everyone (even you, Nathan?) agrees that man has had a negative impact on the environment. Now what? Is there anything we can do to slow, stop or reverse these effects? Everyone wants to go to heaven, but no one wants to die. Everytime I hear a story about the environment, I am in my car driving to work. So, why don't I ride the bus? I ask myself that almost every day, but I change my behavior. And I ride the bus for free! Talk about saving me money, let alone being less of an impact on the environment.

At the risk of monopolizing Nate's blog, let me put another 2 cents in.

First, I think we need to get the oceans to hold much much more biomass, both to get CO2 out of the atmosphere and to produce more food. We need to farm (part of) the oceans on a large scale, not hunt everything to extinction in a huge commons.

Second, we need to rebuild the lost ecosystems where the deserts mentioned above are now (this is a LOT more than just planting trees), for the same reasons as farming the oceans.

And as long as we're exploring the implausible, I think we should build a massive complex of solar cells in high orbit around the equator to block some of the incoming solar radiation and generate enough power to partially offset our use of fossil fuels. We could connect them to Earth with a Skyhook made from carbon nanotubes. Sounds pretty far-fetched, but there are people working on the skyhook as we speak. Along these lines, we should pave roads and the tops of buildings white to reflect as much sunlight back into space as possible.

I don't think any of these will quite do the trick, but they're much more palatable than the fourth part, which is to get the human population down to a far lower level than what it is now and keep it low. With more and more third world countries trying to become first world consumers, the number of people the earth can perpetually support keeps dropping. I doubt it could support even 100 million first world consumers perpetually, and we're pretty far past that already.

Perhaps terra-forming Venus, or mining the asteroids, or colonizing the Moon or Mars will help postpone the Malthusian catastrophe on Earth. But since we haven't a clue as to how to use our resources in a sustainable manner, we'd just ruin those places too.

Hey, Josh!

Antarctica is a desert that didn't undergo man-made deforestation.

That having been said, I believe that mankind is the primary creator of deserts and responsible for desertification, regardless of whether it is the sole cause or not. And I also believe that we have a survival imperative to regrow an assload of trees where there is now nothing but desert. And it won't be easy.

We also need to fix the seas. Fixing the seas is both more simple and more complex than it seems.

I think it can be done by borrowing concepts from New Zealand and Iceland. New Zealand sets aside 90% of it's coastal waters as marine reserve at any one time. You can't fish in it at all. Not for sport, not commercially, not for any reason. They've experienced a vast and rapid jump in the size and number of fish that are caught in the 10% that is fished.

Iceland did something different: they sold the ocean. The assigned property rights to the ocean. Anyone can buy a specific plot of ocean. This changed the dynamic dramatically. Now, if your spot is barren, you don't get any fish. Suddenly, conservation groups bid for some of the richest areas. By creating a market, and hence giving the open seas a price, Iceland began to internalise externalities. Iceland now has one of the world's only sustainable cod fisheries - and here in Scotland, people believe that you can't fish the fish out of the ocean ("Just look at it! It's too big!" one fisherman said to me, gesturing across the Moray Firth, which I know to be about 90% denuded from WWII stock levels).

Josh is right when he says that the earth can only support about 100 million first world consumers. I don't think that the U.S. has the luxury of reforesting the world to the tune of a land area the size of Poland each year for the next sixty years - which is what it would take just to offset our carbon footprint.

I'm forced to fly a lot - which bothers me - but I walk to work. And resist working in places where I can't walk to work.

I guess you're right about Antarctica. But if there WERE trees there, we would have cut them all down by now, so it's the exception that proves the rule somehow.

I know I don't do enough to reduce my carbon footprint and such. But I drive a motorcycle that gets 68 mpg. That's got to count for something, right?