Are forests a good thing?

reversing deforestation is a smart approach to climate change - locking all that carbon back up in trees, right? Maybe not.

A new paper out of Lawrence Livermore throws an odd monkey wrench into the conventional wisdom, using model simulations to conclude that grassland cools while forest warms:

Climate effects of global land cover change
GEOPHYSICAL RESEARCH LETTERS, VOL. 32, L23705, doi:10.1029/2005GL024550, 2005

Abstract

When changing from grass and croplands to forest, there are two competing effects of land cover change on climate: an albedo effect which leads to warming and an evapotranspiration effect which tends to produce cooling. It is not clear which effect would dominate. We have performed simulations of global land cover change using the NCAR CAM3 atmospheric general circulation model coupled to a slab ocean model. We find that global replacement of current vegetation by trees would lead to a global mean warming of 1.3°C, nearly 60% of the warming produced under a doubled CO2 concentration, while replacement by grasslands would result in a cooling of 0.4°C. It has been previously shown that boreal forestation can lead to warming; our simulations indicate that mid-latitude forestation also could lead to warming. These results suggest that more research is necessary before forest carbon storage should be deployed as a mitigation strategy for global warming.

An old reference I recall out of a book. A planet covered entirely in white daisies would cool down, because they light color would reflect the sunlight, and therefore the heat. Whereas a planet covered by black daisies would heat up, because they would trap the sunshine.

So, obviously, what we require is a new breed of fast-growing, all-white trees which slurp up CO2 like a Hummer at a gas station. Come on, genetic engineers...

It's already looking pretty white up here :-)

the planet reched a kind of stability{not that things don't change} with a lot of trees around.

the more we cut trees down the more things heated up -- not that trees alone are the culprit --

and that says nothing about possibly changing the oxygen ratio with fewer trees.

that's just my two cents -- won't even get you a cupa'joe.

The trees trapped more heat from the sun than grassland. As we cut them down, we let that heat go, but we also reduced the CO2 exchange capacity, and we started adding our own CO2 to the mix. Now, if we replanted all the trees, they would start trapping heat again, as well as exchanging CO2. So the net increase in heat would be larger--at least for awhile--if you still had all that trapped heat that the trees would hold down.

That's my understanding of the theory. Not saying it's right or wrong, but that's how I think it goes.

'cause that's sorta how i was thinking.

in the LONG term it seems to me that grasslands would be a poor substitute for what we're looking for.

some of what must come into play is that we can't replace the trees we've cut down -- just an impossibility at this point.

Nature has kept the climate stable for tens of thousands of years by covering the earth with forests. THAT is the model that we should be looking to for guidance.

Global warming IS occurring. 80% of the earth's forest biomass has been removed or severely damaged and depleted in the last 100 years--due to mechanized logging, industrialization and predatory capitalism, which are also causing humans to pour large amounts of green house gasses into the atmosphere that were not there before. IN these radical new conditions, which WE have created, the climate IS going wacko. The polar and Greenland ice caps are melting. The weather is drastically changing, and, among other things, an unusual number of high powered hurricanes are lashing coastal areas, as predicted by global climate change models. Cold periods have become longer and more severe, as have periods of drought. The gulf stream is vanishing. Ocean fisheries are vanishing. The ocean temperature is rising. It does not take a rocket scientist to figure out WHAT is going on here.

The earth--and that thin blue layer that surrounds it like a delicate halo, and that sustains all life that we know of--is responding to what we have done to it: drastically altered the delicate balance of all of the elements in which life has prospered. And one of the biggest and most profound alterations that we have caused is the reduction of the earth's forest cover.

Lawrence Livermore serves the interests of the nuclear industry, corporations and the military. This "study" will be a convenient citation for those who wish to brainwash the pubic that continued deforestation is okay, and that predatory corporations are not polluting, depleting, plundering and destroying the "web of life" for short term profit.

And I'd bet money on the probability that this LL "study" has been skewed toward those interests. I've seen such "studies" before, and they do it by leaving things out (important parameters), and by exaggerating parameters to an extreme and unnatural degree. For instance, the LL model posits "global replacement of current vegetation by trees." The earth was never all trees. It is a mix--and to produce and sustain life, a DELICATE mix--of forests, grasslands, mountains, plains, polar zones and tropics, rivers, beaches, oceans and deserts, all of which is RESPIRING, breathing the atmosphere in and out, and all of which is twirling through space, and getting tugged at and squeezed, under the influence of sun and moon. What do they mean by "current vegetation"? Every green spot on earth, no matter how little it is--say, land with sagebrush on it, or the Serengeti plains--is suddenly covered with trees? What do they mean by "global replacement"? And what do they mean by "trees"? (There are 20 foot diameter, 300 foot tall redwoods, in a complex ecology that creates its own rain, and there are thin, artificial tree plantations, with far less biomass and ability to absorb carbon dioxide, and with low biodiversity and unnatural water flows. What SORT OF FOREST did they posit?)

The evolution of life, and the sustaining of life, involve BALANCE. "Global replacement of current vegetation by trees" would be extreme, not balanced. Also, "current vegetation" and all other current conditions have been profoundly impacted by our activities. If you could go back 100 years--before industrial logging and large scale pollution of air and water--you do NOT HAVE melting polar ice caps and all the other obvious symptoms of global warming. (And "global warming" does not necessarily mean "warm"--it means DISORDER--unusual colds, unusual hots, as with a "fever" that gives you chills.) And if you posit CURRENT, highly altered conditions, and then do something drastic to it--cover it all over with "trees"--what are you proving, except that more disorder will happen, with more large scale, artificial, human interference?

God only knows how we can reverse "chaos theory" in this case (the case of all life and all human civilization going down, in the next 50 years). Chaos theory is basically the theory of unintended consequences. It derived from climatologists who were, as a matter of fact, trying to create computer models to predict the weather--and they found that they COULD NOT. Why? Because it is TOO COMPLEX.

What does our natural instinct tell us, when life becomes just too complex, when life "in the fast lane" gets to us--too many people, too many cars, too much carbon dioxide choking our lungs, too many hassles, too much bureaucracy, too many worries? Our natural instinct tells us to GO HOME. "Home" in this case is the earth 100 years ago. We may never be able to understand how THAT earth achieved the BALANCE that produced us and all life on earth, but we do know this: THAT is where we are SAFE. And THAT earth had about 50% more forest cover than this one does.

But you don't provide any evidence to support your assertion that something is wrong with the model used in the study. Given what you wrote, I'm pretty sure you didn't even read the abstract.

The land that we have is all there is. No great amounts of land to put big forest in any way! So your study is just a dreaming. I would like it if we could. Because your study doesn't count all the ways trees help. But think we can take back land to plant new forest or even replant old one is not going to happen. So why worry about something that's not going to happen. Man just cuts it down. Never plants back. Some tree crops are replanted but most times just cut it down!!!

Also one study doesn't make it fact. Asked the same question to Arbor day people see what you get.

They are behind planting trees. In cities trees work to bring the temp down. I quess we just want to put another strip mine in its place or oil well yeah that will help with the heat.

Also after trees are gone topsoil washes away. So what are you going to replant into!!

They arrest topsoil erosion, they buffer water, they are the habitat for many plants and animals that will probably disappear without them. If they have any net-warming properties, I assume that wasn't a problem before humans started fooling with the CO2 and methane concentration in the atmosphere.

understand--the highly complex "web of life" that sustains us. In ancient, unlogged redwood forests, for instance, there is a barely noticeable fungus that only grows at the bases of the most ancient trees. Nobody knows what its function is in that highly complex ecology. Remove all the old trees, and you wipe out that apparently insignificant fungus. Perhaps it contained a vitamin needed by mice, which in turn transferred a mineral to the northern spotted owls who eat the mice, that fortifies the owls' egg shells. Who knows? The removal of owl habitat (big old trees) then, combined with a slight weakening of their eggshells, is responsible for the failure of their young to thrive (one of the phenomena that is leading to their extinction).

All we know is that, with the ancient forest IN TACT, the owls thrive. And if we go in there with high-powered tractors, and armies of loggers, and remove all the old trees and 80% of the forest volume, and open the canopy to the sun, and chew up the ground with logging operations, and pollute the streams with mud, and poison unwanted (non-commercial) tree species with pesticides, SOMEHOW, the owls don't thrive, nor do the fish or anything else. The impacts are gross and obvious. But, really, we have no idea what-all we have destroyed. The function of that fungus that only grows on old redwoods, and that may transfer a mineral to the owls' eggs, may be THE key factor in the owl's ability to recover. The tipping point. The very edge at which an ecology collapses forever.

Similarly, with global warming, what we know is that, with earth's ecology as it was 100 years ago--before deforestation and pollution--the climate was stable. We have grossly interfered with things. What is the key factor? (i.e., the "chaos theory," the tipping point, the unknown complication that changes everything; that pushes a whole lot of other complications, massed together, over the edge). Since we may never know what that is, the wisest course is to STOP WHAT WE ARE DOING and return to stasis as quickly as possible.

That "unwanted" tree species, that I mentioned above, is an interesting item. It is the tanoak tree--a tree whose bark was used to cure leather (in the period of high leather use). It is native to the redwood forest, but it now has no commercial value. When the logging companies come in and clear-cut an area (removing and selling all the high end species for lumber--redwood, Douglas fir), what the earth does in response to that assault is to IMMEDIATELY begin covering itself with the fast-growing tanaok. The earth acts almost like a naked human immediately trying to cover his/her naked parts, when stripped of clothing. The tanoak environment creates shade, moisture, cooler temperatures, and wildlife habitat (including spotted owl habitat). In natural forest succession, this environment encourages young redwoods and Doug fir, which eventually overtop the tanoak, and reassert dominance, creating a high volume, deep, dark, wet forest environment (in which the strongest, best, most fine-grained wood is created--SLOWLY, over time).

What the logging corporations do, after a clear-cut, is come back in and poison and kill all the tanoak--and then try to grow redwood and Doug fir in highly unnatural conditions, at which they are very unsuccessful. The resultant redwood is called "yellow redwood"--weak, pulpy, disease-prone wood, hardly suitable for fence posts.

This apparently insignificant, "useless," "non-commercial" species--the tanoak--is trying to tell us something: The earth needs its forest cover in order to produce more life, and to nurture and sustain a diversity of life. It CANNOT produce abundance and prosperity on open, naked, dry, hot ground. (It seems like a no-brainer--deserts have LESS life--but no-brainers need to be re-stated in this era of corporate lies.)

The melting of the polar ice caps and the frequent, big hurricanes, and all the rest, are delivering a similar message: If you drastically alter the conditions in which life evolved and prospers--if you start pouring greenhouse gasses into the atmosphere, and THEN, in ADDITION, remove earth's ability to heal itself, by cutting down all the forests--you WILL destroy the complex, ancient, natural system that sustains you. It is a delicately balanced system of various forces, large and small, that needs all of its parts.

The fools (and greedbags) who poison tanoak (and destroy redwood forests) tell us all kinds of lies about it, just as the gas corporations and the Bush government lie about global warming. It's interesting to think of the greed and the lying--and even industrialization itself--as a natural phenomenon (we humans are, after all, products of this ecological system). A few of us--the rich--are apparently suffering a kind of stupidity, thinking that each can exist as a single tree, sucking up all the water, nutrients and sunlight to itself, and not as a forest, a community of trees and other life that is mutually sustaining. A single, isolated tree is subject to wind-throw, and without a forest sustaining a bird population, may have trouble reproducing. And its nutrients will run out, with no fish, mice and other carcasses feeding the soil. The rich seem suicidal in this respect. Thick-skulled; good at hoarding things, short-term; but unable to grasp the complexity and variety that makes life possible, and that ALL must be sustained, that ALL must prosper, for any one to prosper.

The rest of us want to live, however--want the environment protected, want our planet to survive and prosper in all its rich variety and mystery, and want ourselves and everyone to share in it--with many of us busily thinking how we can outwit the stupids who "can't see the forest for the tree"--and somehow salvage our only home in spite of them. It is a contest between outmoded egocentricity and evolving global intelligence, both of them natural phenomena. And since nature clearly favors abundance and variety (and, hopefully--given all the planets that astronomers are now discovering in distant solar systems--abundance and variety everywhere), I think we, the many, will win, in the end, and will prove that we humans are not some cancerous carbuncle on nature, but are a deeply understanding part of it.

"the wisest course is to STOP WHAT WE ARE DOING and return to stasis as quickly as possible. "

I often think I would like to see some cites create some zoning laws stating that you can't cut down trees in certain districts and you can't build something that exceeds the tree canopy height.