Reply #3: you don't get it [View All]

[enki23]

if the rate has been slowed, then the current alarming rate would have been even *worse* without this response. in other words, if we continue the current rates of deforestation, we will accelerate global warming.

of course, there are other problems with this. trees may be growing and dying faster, but without seeing the actual article (which hasn't been printed yet?) i fail to see how "faster" tree growth in the amazon would make any long-term contribution. the amazon forest keeps all its biomass in the trees rather than in detritus. there are two ways this could have a long-term impact on CO2 levels. the first is that it could start switching over to a more detrital-based system by overloading its own extremely rapid system of turnover. i didn't see anything in the bit i read pointing to such a switch, however, and it would seem pretty damned unlikely in any case.

the other, and the way they seem to be heading, would be if there were a long-term sustained *growth* of the forests themselves. that process would have to continue at a rapid enough rate to maintain the same proposed braking effect. there would have to be *more* forest, more living mass, and this process would have to continue at a rapid rate. we'd have to *keep* adding more forest. but we aren't. and we won't. the trees can grow so high, and can get only so fat, and the creatures living in and on them can only get so abundant. the system can't continue increasing its mass without expanding its borders, or switching to a detritus-producing system.

i don't see anything new here at all, and definitely nothing worthy of calling it a "natural brake on global warming." we know that, given sufficient quantities of other essential nutrients, increased CO2 will result in increased plant growth rates. in the US, that mostly means our corn and soybeans will grow a tiny bit faster, and maybe bigger. that is, so long as we can afford to keep making and delivering gargantuan amounts of synthetic fertilizer. as for the rest of the world... there are few areas for which CO2 is the limiting nutrient, and it's doubtful that it would have much of a real effect. also, our forests have already been largely used up, and are still declining. increased growth and death rates (on a biomass basis) would be largely offset by increased rates of decomposition which would go along with them.

and again, this article doesn't seem to contain much new information, except in that the system of growth and death in the amazon forest has sped up somewhat. we already know our CO2 levels are up. some of this response is to be expected. this is neither a surprise, nor mother nature coming to our "rescue".