Climate Change must be tackled NOW

Climate change skeptics mention the absorption of CO2 by vegetation as a natural mitigator for the artificial greenhouse surplus. I don't think this absorption should be taken for granted:

High-Carbon Tree Growth Rate Falls

Oak Ridge National Laboratory
Source

In 1998, an experimental 10-year-old sweetgum plantation in Oak Ridge National Laboratory's Environmental Research Park showed a 35% increase in growth over a nearby control stand of trees. More wood was produced in the test forest's tree trunks and more fine roots grew in the soil. The 15-m-tall sweetgum trees in the plantation's 25-m-diameter plots grew more because they were being exposed to air containing 50% more carbon dioxide (CO2) than is in the atmosphere, thanks to free-air CO2 enrichment (FACE) technology.
In 1999, the second year of the FACE experiment funded by the Department of Energy, some of the data surprised Richard Norby and his ORNL collaborators Stan Wullschleger, Carla Gunderson, Gerry O'Neill, Paul Hanson, Nelson Edwards, Tim Tschaplinski, Mac Post, Don Todd, and Tony King. The growth rate increase of the experimental plantation was reduced to 15% over that of the control stand. These results differ from those at a Duke University plantation dominated by loblolly pine trees with sweetgum trees in the understory. In the past three years, Duke researchers have observed a sustained growth rate increase of 25% per year in the trunks of high-CO2 pine trees over that of control trees in a normal atmosphere.

"The dramatic growth response we saw in the first year in Oak Ridge disappeared in the second," says Norby, leader of the collaboration at the FACE facility and a researcher in ORNL's Environmental Sciences Division (ESD). "It could be year-to-year variability or a blip in the first year's data because of the sudden increase in CO2 concentration. It could be a short-term response that is not indicative of the long-term response. Some of our data indicate that the growth increase was actually maintained but the extra carbon was not stored in the tree trunks."

Many of the physiological responses observed in the second year were similar to those in the first year of the FACE experiment. "We observed that photosynthesis remained enhanced," Norby says, referring to the process by which plants use the energy from sunlight to convert CO2 and water into sugars needed for growth. "The leaf area stayed the same, and the trees conserved water just as well in the second year as the first."

In both years, ORNL scientists observed that the tree leaf pores (stomata), which allow CO2 to enter and water vapor to escape, were not open as wide in plots receiving the extra CO2. "Trees use more water on sunny days and less on overcast or rainy days," says Norby. "Because of high CO2 in air, they can close their stomata a little on days of high water use and get the CO2 they need while letting out less water. Thus, they draw less water from the ground, allowing soil moisture levels to be higher. Higher soil moisture could result in more activity by microbes that may make more nitrogen available to plants, fertilizing them and promoting their growth."

In addition to the tree growth rate difference in 1998 and 1999 at the FACE facility, ORNL scientists also observed that the leaves of the high-CO2 trees became heavier in 1999, probably because more of the extra carbon was used to produce leaves than increase trunk growth. They also found that the nitrogen concentration of leaves and litter (fallen leaves on the forest floor) was lower, which could retard the cycling of nitrogen and carbon in the ecosystem.

ORNL researchers also observed an increase in production and mortality of fine roots in the second year, resulting in a change in the belowground allocation of carbon. "We saw an increase in carbon cycling because of high root turnover," Norby says. "The fine roots took in more carbon and then rapidly died, releasing more carbon to the soil than usual."

Because ORNL and Duke scientists are doing similar experiments on plantations of equivalent size and age in the same climate zone, they propose to collaborate on a study of nutrient cycling and carbon sequestration in these test forests if DOE funding is available. They will also try to help each other understand the variability in the results from the Oak Ridge and Duke experiments.

-------------

Furthermore, some support the belief that more CO2 in the air will provide more vegetal nutrition stocks and thus promote forest growth. This is also doubtful.

Feel the Heat: Rain forests may slow their growth in warmer world

Sid Perkins, Science News Online
Source

0 Replies

wolf wrote:

Climate change skeptics mention the absorption of CO2 by vegetation as a natural mitigator for the artificial greenhouse surplus. I don't think this absorption should be taken for granted:

... but note that the study you quote provides no evidence for what you're claiming. In the experiment they're referring to, the plants were growing faster in a high-CO2 atmosphere than in a normal atmosphere. The surplus growth varied from year to year, but the plants always grew faster when CO2 concentration was higher. This is just what the biological feedback argument is predicting.

wolf wrote:

Furthermore, some support the belief that more CO2 in the air will provide more vegetal nutrition stocks and thus promote forest growth. This is also doubtful.

The problem with your second article is that lots of things that influence tree growth are changing at the same time. To conclude that warm weather slowed down growth in that forest, you have to control your data for these other influences. Your article mentions no effort to do so, and I suspect they haven't made such an effort. I'd be happy to be corrected though -- just send me a reference to the actual study they mention.

But even if your article's message survived this kind of cross-check, it would only provide evidence about old-growth forests. It says nothing about the overall vegetation on the planet, which is dominated by plankton and new growth forests. If the globe is warming at 5°F a century, plants that are optimized for the climate of the past will grow slower (as your article claims to have measured), and plants optimized for the climate of the future will grow faster. To assess the overall effect of climate change on the earth's vegetation, you have to sum up both effects. But the study your article cites makes no effort to even look at the second effect.

0 Replies

Excuse me, but you're an old nag. That's not an insult, it's an objective fact. You're one of those unsupportable debunkers who get paid to suppress environmental concerns with every possible insanely anal argument you can come up with.

I wish you could apply that same amount of hilarious criticism you so regularly exercise to the essence of the problem: the pollution that threatens the sustainability of this planet. It could make your role as knight of the energy lobbies less transparent.

0 Replies

Wolf,

You are making a fool of yourself. I recognize that in your case not much effort is required, but with your last post you have surely done it. Your comments are quite unrelated to reality and are laced with paranoid flights of fantasy. Perhaps you should seek some help.

0 Replies

How do you mean, 'unrelated to reality'?

0 Replies

george - Ever hear the parable about the scorpion that wants to cross the river? Don't waste time complaining that the scorpion behaves as a scorpion.

0 Replies

wolf wrote:

Excuse me, but you're an old nag.

If that's the best refutation of my arguments you can come up with, that makes me feel very comfortable with my opinion. Still proud of your Nazi apologies, by the way?

Scrat wrote:

george - Ever hear the parable about the scorpion that wants to cross the river? Don't waste time complaining that the scorpion behaves as a scorpion.

Though Bob may know the parable, I don't, but I'd like to. So what's the story?

Thanks!

-- Thomas

0 Replies

Thomas,

The story usually goes something like this:

There is a flood and a man determines to cross the stream before him to escape its effects. As he prepares to wade into the stream he sees a snake (rarely is it a scorpion) and in a gesture of mercy he grabs the snake and stuffs it in his bag, enters the stream and successfully crosses the flood. As he emerges to safety on the other side, he opens the bag to release the snake, and suddenly the snake bites him. Writhing in pain he asks the snake how it could have done this just after he had saved its life.

The snake replied, 'I'm a snake, that's what I do.'

0 Replies

Thanks, George!

0 Replies

George

Yours is a variation, but the actual story features a scorpion and a frog (other versions feature a turtle, fox, etc.). The scorpion asks the frog for a ride across the river and promises not to sting the frog, but half way across the scorpion stings the frog and they are both doomed. When the frog asks why the scorpion would sting the frog and doom himself, the scorpion responds that it is in his nature to sting; he simply can't be other than he is.

I guess your version makes the same point, but I always liked the fact that the scorpion is so tied to his nature that he dooms himself. That's key to the story for me.

BTW, there's also an old buddhist story about a monk meditating by a river. The monk repeatedly reaches into the river to rescue a scorpion which has fallen into the water, and each time the scorpion stings him. An onlooker finally asks the monk "You fool, why do you keep helping the scorpion if he continues to sting you?" The monk responds, "It is the scorpion's nature to sting, and it is a monk's nature to help."

But my point in all of this was simply to suggest that expecting rational discourse from Wolf was expecting him to act contrary to his nature.

0 Replies

Thanks Scrat. Your version suggests the source may be Aesop. Is that possible?

I did detect your point (and I suspect Thomas did too). No argument from me.

0 Replies

georgeob1 wrote:

Thanks Scrat. Your version suggests the source may be Aesop. Is that possible?

I did detect your point (and I suspect Thomas did too). No argument from me.

Almost to the former, and me neither to the latter. There's a website Aesopfables.com, and it turns out that Aesop's version is a scorpion and a ladybug. Whatever the zoology, I agree with the moral of course. And I find it interesting that Scrat's variant, though its plot is farther removed from the original, makes the point even stronger than Aesop did. As Leslie Orgel said: "Evolution is smarter than you are" -- even if you happen to be Aesop!

0 Replies

Thomas, du alte Gaul, your critique of the science I provided is so ridiculously filtered, biased and far-fetched, that you leave me no resort but to namecall you. Again, why don't you criticize the fossil fuel companies, who pollute, wage war on sovereign nations, and undermine sustainable ecosystems all over the planet, with the same relentless amount of zest?

0 Replies

Actually Thomas' comments were sober, restrained and factual. The only "ridiculous, filtered, and biased" comments I have seen here have come from you, Wolf.

0 Replies

Quote:

If the globe is warming at 5°F a century, plants that are optimized for the climate of the past will grow slower (as your article claims to have measured), and plants optimized for the climate of the future will grow faster.

Seems pretty ridiculous to me. And again, Thomas' relentless criticism of climate change warnings is biased. So are you, of course, george. You have gotten me so far as to admit that this was a complex subject, but I haven't seen you recognize the dangers we will face if the climate keeps on shifting away from its current system. I still find that attitude unworthy of an adult individual.

0 Replies

I am willing to bet that what seems "ridiculous" to someone who is "ridiculous" is fact, logic and reason to the rest of the world.

But--unlike some of us--I could be wrong. Cool

0 Replies

wolf wrote:

Quote:
If the globe is warming at 5°F a century, plants that are optimized for the climate of the past will grow slower (as your article claims to have measured), and plants optimized for the climate of the future will grow faster.

Seems pretty ridiculous to me.

That's progress -- at least now you're criticizing a specific point I made, rather than my character. Think about it this way. As the globe warms -- and unlike Scrat and George, I do believe that it does warm -- climate zones move towards the poles, and the flora and fauna of these zones move with them. (We're talking about something like 300 miles per century here, which is a speed at which animals can easily move, and plants can easily spread through pollination.)

Now consider how this process looks to an ecologist who examines a particular piece of land. He finds that some plants that have been growing here for decades come under stress because they are less and less well adapted to the current climate. At the same time, some plants that had been struggling to survive because the climate was just a little bit too cold for them do better and better. But the ecologist doesn't see that, because these newcomers are not yet on his list of species to monitor. He decides that global warming is on net bad for the ecosystem he observes. But this is just an artifact of him using a biased sample.

wolf wrote:

And again, Thomas' relentless criticism of climate change warnings is biased.

Just assume, for the sake of the argument, that the scope of these warnings is way out of line with current research. And assume, again just for the sake of the argument, that I as a physicist am in a position to tell. Why would "balance" between the environmentalists' and the cornucopians' position be a good thing in this case? In fact, why would it even be ethical?

0 Replies

Thomas wrote:

As the globe warms -- and unlike Scrat and George, I do believe that it does warm ...

Um, excuse me, but where exactly did I write that I don't think the globe "warms"? Of course it does; it warms and cools over periods of time and we are only now beginning to try to understand some of the myriad reasons it does so. My gripe is that so many people have convinced themselves that they know what is happening, why, what it will mean in the future, and what we MUST do about it.

0 Replies

Scrat wrote:

Thomas wrote:
As the globe warms -- and unlike Scrat and George, I do believe that it does warm ...

Um, excuse me, but where exactly did I write that I don't think the globe "warms"? Of course it does; it warms and cools over periods of time and we are only now beginning to try to understand some of the myriad reasons it does so. My gripe is that so many people have convinced themselves that they know what is happening, why, what it will mean in the future, and what we MUST do about it.

In our little fight a few pages ago, I understood your position as stating that we just don't know whether the globe has been warming over the last 150 years, and that we don't really know whether this warming was man-made and whether to expect more warming in the next century under a "business as usual" scenario. By contrast, I'm pretty sure on all three counts. I am just as sure that the problem isn't worth fixing, given its cost.

But if I misunderstood your position, I'm sorry, and thanks for the clarification.

0 Replies

Apparently someone or something has gotten you so irrational as to believe this artificial greenhouse effect is not worth mitigating, because nature will adapt just fine. To hell with all the transitory damage humans, their economy and health, will suffer. Vegetation will change worldwide, poles will melt, break up, sea levels are rising, desertification above the equator, diseases, and most of all: major agricultural damage -- this is: damage to our very nutrition and its affordability. You apparently say: no problem, the planet will over time come into a new balance. That's just an unbelievably irresponsible and passive attitude, and that's why you're an old nag: you're not willing to translate the issue into policy, while there is every reason to do so.

Is there, perhaps, a religious Thomas? "Pollution? Inch Allah, and then we'll see." There's an Arab butcher on my street corner that uses the very same line of thinking in order not to recycle his garbage.

I utterly despise that. We are responsible and should act that way. That's what policy is about.

0 Replies

Climate Change must be tackled NOW

Related Topics

Quick Links

My Account

able2know