Deforestation causes cooling, study shows

Nov 16, 2011

Deforestation, considered by scientists to contribute significantly to global warming, has been shown by a Yale-led team to actually cool the local climate in northern latitudes, according to a paper published today in Nature.

"If you cut in the boreal region, north of 45 degrees latitude, you have a net cooling effect," said Xuhui Lee, the study's principal investigator and professor of at the Yale School of Forestry & Environmental Studies. "You release carbon into the atmosphere by cutting down trees, but you increase the albedo effect—the reflection of sunlight."

Lee and a team of researchers from 20 other institutions found that surface temperatures in open areas were cooler because snow cover reflected the sun's rays back into outer space, while nearby forested areas absorbed the sun's heat. At night, without the albedo effect, open land continued to cool faster than forests, which force warm turbulent air from aloft to the ground.

"People are debating whether afforestation is a good idea in high latitudes," said Lee. "If you plant trees you sequester carbon, which is a benefit to the system. At the same time, if you plant trees you warm the landscape because trees are darker compared to other vegetation types. So they absorb solar radiation."

The researchers calculated that north of Minnesota, or 45 degrees latitude, the temperature decreased by an average of 1.5 degrees Fahrenheit. On the other hand, deforestation south of North Carolina, or 35 degrees latitude, appeared to cause warming. In addition, Lee said that "statistically insignificant" cooling occurred between these two latitudes.

The researchers collected temperature data from a network of weather stations in forests from Florida to Manitoba and compared results with nearby stations situated in open grassy areas that were used as a proxy for deforested land.

"The cooling effect is linear with , so the farther north you go the cooler you get with deforestation," said Lee.

David Hollinger, a scientist with the USDA Forest Service and study co-author, said, "Another way to look at the results is that the climate cooling benefits of planting forests is compounded as you move toward the tropics."

The researchers call for new climate-monitoring strategies. "Because surface station observations are made in grassy fields with biophysical properties of cleared land, they do not accurately represent the state of climate for 30 percent of the terrestrial surface covered by forests," the study says.

Explore further: New water balance calculation for the Dead Sea

More information: "Observed Increase in Local Cooling Effect of Deforestation at Higher Latitudes," Nature (2011).

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User comments : 27

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ABSOLUTEKNOWLEDGE
1.6 / 5 (14) Nov 16, 2011
oh no this one must of sleed by the censorring department

u ment to say scientific proff of manbearpig? lieng?

coming up with fairy tail stories how co2 causes global warming
ahh i mean cooling?

and the global elite scam to introduce the co2 tax on human activity meaning u will pay a tax for breathing?

atention psyorg remove article imedialty ur handlers my get upset remove funding or ur url rights and have u on the no fly list in no time

heads up

ps. still not sure censoring/spin department screw up
or one of your sheep woke up?
that_guy
2.3 / 5 (4) Nov 16, 2011
This is what happens when you mix good science and bad science.

Locally, cutting down trees will cool things down. But it will heat things up elsewhere.

The study fails to address several very key questions that apply to this situation.

1. Does the net cooling affect apply on a global basis? They imply it does, but I see no information supporting that over other conclusions. They only studied areas on a nominally local basis. Plug it into the models before you imply wider conclusions.

2. As the world gets warmer, how does this effect change? Assuming the world gets warmer overall, the competing mechanisms would interact at 45 degrees latitude, and the albedo effect would diminish at this juncture. As that happens, the deforested area would then begin to contribute to warming instead, and become a warming feedback mechanism.
ABSOLUTEKNOWLEDGE
Nov 16, 2011
This comment has been removed by a moderator.
that_guy
4.3 / 5 (6) Nov 16, 2011
the c*** im quoting its obviously from the land of manbearpig
and cant handle the truth so trys to spin it

in effect providing damage control for the censoring department

The science minded of us prefer to know the whole picture, good or bad. Notice that I didn't dispute their research, I wanted the obvious follow up questions answered.

It's the difference between us believing that the sun is a big fiery god traveling across the sky every day, and knowing that it is actually a huge ball of hydrogen fusing in to helium.

I prefer to question things until I get all the answers rather than spout off like an ignorant twit.
ABSOLUTEKNOWLEDGE
1.3 / 5 (13) Nov 16, 2011
u good place u can get an idea about a alternative opinion on the global warming theory is here

for those who dare

http://iceagenow.info/

truth fears no investigation
omatumr
1.3 / 5 (13) Nov 16, 2011
Regretfully the worldwide entanglement of government science, politics and economics started about four decades ago [1] and destroyed the credibility of scientists, world leaders and economists.

1. "Deep Roots of the Global Climate Scandal (1971-2011)"
http://dl.dropbox...oots.pdf

Now social unrest is increasing and the public has little or no confidence in political leaders.

http://chiefio.wo...et-mess/

http://judithcurr...climate/

www.theepochtimes...214.html

Regretfully, that is where we are today.

Oliver K. Manuel
Former NASA Principal
Investigator for Apollo
http://myprofile....anuelo09
Pirouette
3 / 5 (4) Nov 16, 2011
Hmmmm. . . .now wondering if Richard Muller mentioned everything that is in the above article to the House Committee in his former global warming skeptic testimony.

"What fools these mortals be" - Puck
flicktheswitch
3.7 / 5 (6) Nov 16, 2011
hey joe pseudoskeptic guy i know more about the big picture then u will ever get a glimpse of if u live 1000 years
and im not only talking about wheather on a planet called earth

sheep dismissed

check my name little pseudoskeptic twat it means what it says


As far as I'm aware the bare minimum educational standard for someone in the scientific community to have anything remotely approaching "Absolute Knowledge" about a topic would be the ability to use the English language correctly, and string a logical argument together.

Since you come across as a ego-sensitive 15 year old I highly suspect you fall into one of two camps:
1) Troll.
2) Single issue hot-button crank.

Either way, your input is largely useless to us.

On the article itself:
Interesting stuff. Personally I think any additional data or angle is worth it if you're in search of something as elusive as 'truth'. Time will tell on this one, I guess.
jahbless
1 / 5 (1) Nov 16, 2011
"You release carbon into the atmosphere by cutting down trees.."

Come again? Because of the fossil fuels used in the chainsaws, he means... right? Because reducing photosynthesis is not quite the same thing as releasing carbon, is it??
Howhot
3.7 / 5 (6) Nov 16, 2011
This is probably the lamest science paper I've read in a while. Basically as the article was summed up, clear trees at the outer rims of the north and south polls and the it gets colder do to more snow cover. First problem; with global warming, can you even guarantee there will be a snow cover? The polar caps are already melting so how can you be sure that you won't just make global warming worst?

It just a dumb idea all over the place IMHO.
jsdarkdestruction
3.5 / 5 (8) Nov 17, 2011
Oliver Manuel's recent efforts to plaster Physorg.com and other public news sites with his theories and personal URLs are a bit puzzling, as scientists have a variety of publications available to communicate directly to each other in. My best guess is that he is desperately trying to prop up his legacy in light of his arrest in his university office on 7 charges of rape and sodomy based on allegations by 4 of his own children. The charges have been reduced to one count of felony attempted sodomy, not necessarily because of his innocence, but because of the statute of limitations. One can only guess how the recent charges and decades of family strife have affected his ability to reason rationally and to remain objective while defending his unpopular theories.

http://www.homefa...uel.html

http://mominer.ms...hildren/
mosahlah
5 / 5 (1) Nov 17, 2011
I doubt that bit of science will make it into the mainstream media.
ABSOLUTEKNOWLEDGE
1 / 5 (5) Nov 17, 2011
Oliver Manuel's recent efforts to plaster Physorg.com and other public news sites with his theories and personal URLs are a bit puzzling, as scientists have a variety of publications available to communicate directly to each other in. My best guess is that he is desperately trying to prop up his legacy in light of his arrest in his university office on 7 charges of rape and sodomy based on allegations by 4 of his own children. The charges have been reduced to one count of felony attempted sodomy, not necessarily because of his innocence, but because of the statute of limitations. ``

u dont have to atack him personally

is sufice to say anybody working for nasa in higher position is a low life scum not worthy to bread air, for knowing about the alien presence on earth moon mars the ruins there
and not teling the world

on a second tghoutgh your right only a child molesting piece of shit like
him could keep that secret
ABSOLUTEKNOWLEDGE
1 / 5 (3) Nov 17, 2011
As far as I'm aware the bare minimum educational standard for someone in the scientific community to have anything remotely approaching "Absolute Knowledge" about a topic would be the ability to use the English language correctly, and string a logical argument together.

Since you come across as a ego-sensitive 15 year old I highly suspect you fall into one of two camps:
1) Troll.
2) Single issue hot-button crank.
I guess.

made me smile:)
u just proved my point like u analyzed me based on a few post reached a logical an probable conclusion

regarding how close i am to absolute knowledge

the only problem is u could be no farther from the truth

in the same way u do analyze so called scientific articles
and reach good valid conclusions based on them only problem
again have nothing to do with reality/truth

let me give a you a hint in life
only 5% of available knowledge is public available for you
95% is by invitation only
just so happens i have access to it = absolute knowledge
rubberman
4 / 5 (4) Nov 17, 2011
I think Absolute knowledge just escaped his cartoon prison, landed in the real world, but still thinks he's back home in the land of 3 fingered villains....welcome to Physorg Stewie!
@jahbless - - Ya it was poorly worded, although you were bang on with the whole chainsaw thing! I beleive they are referring to the ability of trees to sequester carbon, therefore cutting them down "adds" carbon to the atmosphere by reducing the amount absorbed from it....
By the way Stewie, how does someone with as much knowledge as you claim to have find themselves passing the time posting incoherent jibberish on science websites? Just curious because I also know everything....I just like the banter.
SteveL
5 / 5 (2) Nov 17, 2011
Ah AK, if only you had access to your meds. AK, your rants are even less viable than OKM's. While he tries and at least brings links and some data, though often valueless in my opinion, to the discussion, you bring and provide nothing to the topic. Your words have no value.
ABSOLUTEKNOWLEDGE
1 / 5 (5) Nov 17, 2011
I think Absolute knowledge just escaped his cartoon prison, landed in the real world, but still thinks he's back home in the land of 3 fingered villains....welcome to Physorg Stewie!
@jahbless - - Ya it was poorly worded, although you were bang on with the whole chainsaw thing! I beleive they are referring to the ability of trees to sequester carbon, therefore cutting them down "adds" carbon to the atmosphere by reducing the amount absorbed from it....
By the way Stewie, how does someone with as much knowledge as you claim to have find themselves passing the time posting incoherent jibberish on science websites? Just curious because I also know everything....I just like the banter.


well the world u live in and posters here seems like the cartoon so cant help to jibe in sometimes couse im in disbelief
albert ainstein famous quote comes to mind
most people are stupid

so it implies most people with scientific background are stupid

thats why i post
antialias_physorg
5 / 5 (3) Nov 17, 2011
most people are stupid

thats why i post

Consider yourself then one of that majority. Your postings have certainly earned you a place among them.

And no: "Most people are stupid" is not a quote attributable to Einstein.
ABSOLUTEKNOWLEDGE
1 / 5 (5) Nov 17, 2011
Ah AK, if only you had access to your meds. AK, your rants are even less viable than OKM's. While he tries and at least brings links and some data, though often valueless in my opinion, to the discussion, you bring and provide nothing to the topic. Your words have no value.


i speaking from a position of such higher knowledge then u and the other avarage joes posting here that links claims of proff would be futile

so just state the facts
i have nothing to prove

so that future ai bots scanning the archived internet would know there were people in the know back in this century

not just stupid brain washed zombies like urself
Pirouette
3.5 / 5 (4) Nov 17, 2011
AK. . .perhaps if you displayed a better command of the English language, (spelling, syntax, etc.), you might be taken more seriously. I recognize your "tongue-in-cheek" comments as such through my own sense of humour. Not everyone does.
However, if you are simply a troll looking for attention, then kindly disregard all of the above.
that_guy
5 / 5 (1) Nov 17, 2011
"You release carbon into the atmosphere by cutting down trees.."

Come again? Because of the fossil fuels used in the chainsaws, he means... right? Because reducing photosynthesis is not quite the same thing as releasing carbon, is it??


When plants, such as trees decay, the process releases carbon dioxide. In a stable biosphere, that is more than offset by the other plants in the area. If you replace the trees with smaller plants, you re-capture less of that carbon.

the CO2 released by chainsaws and other equipment is somewhat tertiary in this case.
Pirouette
3 / 5 (2) Nov 17, 2011
The planting of replacement trees is vital to taking up the CO2 released by the felling of and normal decay of big trees. In a forest of pines, for example, when the loggers come in and take down the choicest trees, there are always some that are felled either by accident or because they just happened to be in the way of the trucks. In my area I see this year after year. The trees are left on the ground to rot instead of being loaded onto the trucks. It's such a waste of good wood. And the land lies fallow for some years before the owners decide to grow more saplings or till the soil to raise crops. Weeds will grow but they do not take up as much CO2 as the pine forest that once stood there. I prefer to replant as soon as possible.
ka_
not rated yet Nov 20, 2011
Whereas interesting to see an alternative idea about global warming and deforestation, I am not so sure the study is right as:
1) During winter time these regions receive less sun regardless
2) During summer time these areas would normally be green and not covered with snow
3) Among the reasons the temperature within forests typically is higher is that there is that the air is standing still, whereas on open areas wind will bring cold air!
4) That within the forest there is a shelter does not say anything about the lager picture - the temperature lets say 100 meters ABOVE the forest top in comparison with 100 meters ABOVE the deforested areas. We might find the forest a mostly closed ecosystem in this sense just like we would not measure the winter vs summer temperatures inside the rock of the mountains.
5) When the sun has been up for a few hours, the temperature will typically be much higher in the deforested areas than in the forests.

Deforestation will lead to more extreme climate
SteveL
not rated yet Nov 20, 2011
According to this article, the Amazonian slash & burn deforestation (<35 degrees latitude) could be doing more damage than previously considered.
Callippo
1 / 5 (1) Nov 20, 2011
The deforestation could really cool the atmosphere, but it will make it more dry too. We should separate two aspects of climatic change - the rising of temperature and the rise of droughts. Actually there is no reason for hawing more dry atmosphere, when the temperature is rising. Whereas I've many evidences of the geothermal origin of global warming, the explanation of droughts is not so straightforward at all and it could be of the anthropocentric origin quite easily. The production of aerosols increases the number or condensation nuclei, so that the droplet of water remain smaller and they cannot coalesce and to fall to Earth. The presence of global warming has nothing to do with this fact, no matter whether it is of anthropogenic origin or not.

The rising of global temperatures is not so big problem for contemporary civilization, the droughts and spreading of deserts is. So we should protect our tropical forests by all means possible.
Callippo
1 / 5 (1) Nov 20, 2011
The protection of tropical forest has its another reason in protection of genetic diversity, which is conserving the products of billion years of evolution. The conservatively thinking people, who are supporting free market don't care about price of endangered species, until it cannot be expressed with money. They don't care, if we destroy many precious species, which may contain the cancer cures or which could lead us to various technological solutions, until we cannot exploit them right now. This is because free market economy always operates with current prices, so it doesn't care about future and it's not even able to drive itself - and we are suffering with periodical economical crisis. Briefly speaking, the economical mechanisms, which are working well at the local level cannot be applied at the global level and vice-versa: the socialism and centralized planning isn't applicable for driving of economy at the communal level. The people need to realize these connections urgently.
Callippo
1 / 5 (1) Nov 20, 2011
You release carbon into the atmosphere by cutting down trees, but you increase the albedo effectthe reflection of sunlight
It's disputable if we consider, the trees are collecting the water, so that the forests are the source of many clouds, which are reflecting the sun light.
surface temperatures in open areas were cooler because snow cover reflected the sun's rays back into outer space
This cooling effect may work only when you would have some snow in inland areas. But if we cut the trees, we would face the droughts and the lack of snow there, so that the net cooling effect may become negligible or even negative (we will lose the snow cover even outside of forests).

Such studies therefore can be impeached quite easily, because they don't consider all connections, which may apply here.
astro_optics
1 / 5 (1) Nov 20, 2011
OK then, I'll take the axe to that tree in my backyard :)