Forest health versus global warming: Fuel reduction likely to increase carbon emissions

Dec 20, 2011
Forest thinning, such as this work done in the Umpqua National Forest in Oregon, may be of value for some purposes but will also increase carbon emissions to atmosphere, researchers say. (Photo courtesy of Oregon State University)

Forest thinning to help prevent or reduce severe wildfire will release more carbon to the atmosphere than any amount saved by successful fire prevention, a new study concludes.

There may be valid reasons to thin forests – such as restoration of structure or health, wildlife enhancement or public safety – but increased carbon sequestration is not one of them, scientists say.

In research just published in Frontiers in Ecology and the Environment, Oregon State University scientists conclude that even in fire-prone forests, it's necessary to treat about 10 locations to influence fire behavior in one. There are high carbon losses associated with fuel treatment and only modest savings in reducing the severity of fire, they found.

"Some researchers have suggested that various levels of tree removal are consistent with efforts to sequester carbon in forest biomass, and reduce atmospheric carbon dioxide levels," said John Campbell, an OSU research associate in the Department of Forest Ecosystems and Society. "That may make common sense, but it's based on unrealistic assumptions and not supported by the science."

A century of fire suppression in many forests across the West has created a wide range of problems, including over-crowded forests, increased problems with insect and pathogen attack, greater risk of catastrophic fire and declining forest health.

Forest thinning and fuel reduction may help address some of those issues, and some believe that it would also help prevent more carbon release to the if it successfully reduced .

"There is no doubt you can change fire behavior by managing fuels and there may be other reasons to do it," said Mark Harmon, holder of the Richardson Chair in Forest Science at OSU. "But the carbon does not just disappear, even if it's used for wood products or other purposes. We have to be honest about the carbon cost and consider it along with the other reasons for this type of forest management."

Even if wood removed by thinning is used for biofuels it will not eliminate the concern. Previous studies at OSU have indicated that, in most of western Oregon, use of wood for biofuels will result in a net loss of carbon sequestration for at least 100 years, and probably much longer.

In the new analysis, researchers analyzed the effect of fuel treatments on wildfire and carbon stocks in several scenarios, including a single forest patch or disturbance, an entire forest landscape and multiple disturbances.

One key finding was that even a low-severity fire released 70 percent as much carbon as did a high-severity fire that killed most trees. The majority of result from combustion of surface fuels, which occur in any type of fire.

The researchers also said that the basic principles in these evaluations would apply to a wide range of forest types and conditions, and are not specific to just a few locations.

"People want to believe that every situation is different, but in fact the basic relationships are consistent," Campbell said. "We may want to do fuel reduction across much of the West, these are real concerns. But if so we'll have to accept that it will likely increase carbon emissions."

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JDoddsGW
1.1 / 5 (7) Dec 20, 2011
Who cares about carbon emissions.
According to some "nut" named Isaac Newton. You can NOT create or destroy energy (ie heat!) that means that more CO2 can NOT by itself cause warming UNLESS you get more warming energy from somewhere elasr. In that case it is the warming energy , NOT the Co2 that causes global warming, so I repeat who cares abour CO2 emissions. Stop wasting my money
GSwift7
1.9 / 5 (9) Dec 20, 2011
The spokesperson here appears to be unaware that, in addition to what they are saying, there is another reason that thinning can actually decrease the amount of carbon a forest will sequester over long time scales. The hotter fires that thinning will prevent tend to produce more char, deeper in the soil, than a less intense fire would produce. Char is a relatively stable form of carbon, and is able to semi-permanently sequester carbon in the soil, but it take a sufficiently hot fire to do this. Also, the material that is converted to char would otherwise have eventually decomposed or been consumed by organisms, which leads to GHG's which are worse than co2, such as methane and nitrous oxide.
Vendicar_Decarian
3.1 / 5 (8) Dec 20, 2011
Yup, blankets can't keep you warm because they don't in themselves produce heat.

Well Done Mr. JDobbs.

You do realize that you are posting do a science forum, don't you? Is your sentience sufficiently developed for you to be aware that you are?

Apparently not.

"According to some "nut" named Isaac Newton. You can NOT create or destroy energy (ie heat!) that means that more CO2 can NOT by itself cause warming" - JdobbsTard

Pirouette
1.7 / 5 (6) Dec 20, 2011
This article is yet another example of junk science, presumably costing taxpayer money. The trees in a forest sequester CO2 naturally because CO2, amongst other nutrients, is what they EAT.
And when ANY individual tree dies, the CO2 is released from its cells, then that GAS is freely absorbed by yet another tree that's still alive. Thinning a DENSE forest serves the purpose of allowing sunlight to reach healthy young saplings and other tree growth which will replace the older timber eventually, BUT, as GSwift7 points out. ""thinning can actually decrease the amount of carbon a forest will sequester over long time scales."" . That's because the loss of sufficient trees through thinning removes the CO2 sequestering by that much, i.e. the volume of living tree matter versus the CO2 it could have absorbed if it had been left alive.
Pirouette
1.6 / 5 (7) Dec 20, 2011
The American Indians (native Americans) would occasionally thin out a forest of too many trees and set fire to prairies to thin out underbrush to try to prevent forest fires later on that would devastate their supplies of wood. The leveled trees that they cut down were used for firewood and dugout canoes. They were not aware of the "hazards" of CO2 emission from dead trees, so I suppose that American Indians contributed to global warming prior to the arrival of White men. Not mentioned in the article is, of course, forest fires naturally caused by lightning, therefore, lightning is also a cause of global warming. Why, even Mother Nature can be accused of destroying the environment.
Howhot
2.6 / 5 (5) Dec 20, 2011
The spin doctor "Pirouette" editorializes;

This article is yet another example of junk science, presumably costing taxpayer money.


Your point being that you a not a scientist, you would not know junk from the car you drive (if your not living in your mom's basement) and you only know there is vitamin C in orange juice.
That sounds like the extent of your so called "science background". Your spin on this article is like goofy. Fire from dugout canoes? I mean really like that impacts the the GIGATONS of CO2 release from coal fire plants daily.

If you and G7 are so worried about sequestering CO2, just stop burning the already sequestered CO2 sinks. Daahhhhh.

Pirouette
1.8 / 5 (5) Dec 21, 2011
The spin doctor "Pirouette" editorializes;

This article is yet another example of junk science, presumably costing taxpayer money.


Your point being that you a not a scientist, you would not know junk from the car you drive (if your not living in your mom's basement) and you only know there is vitamin C in orange juice.
That sounds like the extent of your so called "science background". Your spin on this article is like goofy. Fire from dugout canoes? I mean really like that impacts the the GIGATONS of CO2 release from coal fire plants daily.

If you and G7 are so worried about sequestering CO2, just stop burning the already sequestered CO2 sinks. Daahhhhh.



Howsnot seems to presume a lot about me. The car I drive? Vitamin C in orange juice? WTF are you talking about. Have you been to see your psychiatrist yet? If not, you really need to make an appointment and tell him all your troubles, because you are evidently delusional about people you don't even know.
Pirouette
1.7 / 5 (6) Dec 21, 2011
Howsnot needs to reread my comments because now he/she thinks that fire comes from dugout canoes and I never said that.
And he/she is talking about coal fire plants when the article is exclusively about THINNING OUT TREES THAT EMIT CO2. . .NOTHING IN THE ARTICLE ABOUT COAL FIRE PLANTS, DIMWIT. LEARN TO READ AND COMPREHEND WHAT WAS SAID BEFORE YOU GO OFF HALF-COCKED ABOUT WHAT SOMEONE ELSE HAS SAID, YOU DIMWIT. YOU'RE NO SCIENTIST EITHER, MAYBE JUST A LAB TECH THAT DOES BLOODWORK AND DREAMS OF BECOMING A SCIENTIST. THAT'S ALL. LOL. . .WHAT A TROLL!
Howhot
2.6 / 5 (5) Dec 21, 2011
Lol. Nice spin Pirouette. I think that people reading your posts, vs my post will see who is the troll. The point of the article is that the GIGATONS of excess CO2 from burnt fossil fuels (and A.G. Warming) has evaporated water from the soil in certain geographic areas, that the trees will never recover. Its just one more consequence of coal-oil global warming.

Agreed?
Pirouette
1.7 / 5 (6) Dec 21, 2011
LOL. . .nice spin Howsnot. I think that people reading your posts vs. MY post will see that Howsnot is the troll.
And WTF are you talking about again? I TOLD YOU ALREADY that this article is NOT about coal or oil, yet you PERSIST in avoiding the real issue of the article. FORESTS - TREES - BURNING - THINNING. What does thinning of trees have to do with coal fire plants, dimwit? ARE YOU PHUCKING INSANE? CAN'T YOU READ ENGLISH? Go back to your crack pipe and dream some more, Howsnot.
Pirouette
1.7 / 5 (6) Dec 21, 2011
First of all, Howsnot. . .TREES ARE NOT A FOSSIL FUEL. TRY TO WRAP YOUR HEAD AROUND THAT. TREES ARE A LIVING ORGANISM UNTIL THEY ARE CUT DOWN AND DIE, AND WHEN THEY DIE THEY EMIT THE CO2 THAT THEY HAD SEQUESTERED AKA ABSORBED WHILE THEY WERE ALIVE. CAN YOU UNDERSTAND THAT MUCH, HOWSNOT? IT'S VERY EASY TO UNDERSTAND, A FIRST GRADER CAN UNDERSTAND IT, BUT YOU SEEM TO HAVE TROUBLE UNDERSTANDING THE CONCEPT AND PERSIST IN TALKING ABOUT COAL AND OIL.
I REPEAT. . .TREES ARE NOT FOSSILS UNTIL THEY HAVE BEEN KILLED. GOT IT? YOU CLAIM TO BE A SCIENTIST, , , ,WHAT KIND OF SCIENTIST? CLOWN COLLEGE?
Pirouette
1.7 / 5 (6) Dec 21, 2011
AND EVEN WHEN TREES ARE KILLED, THEY ARE STILL NOT FOSSILS. . .THEY BECOME FIREWOOD, OR THEY DECAY AND BECOME FOOD FOR TERMITES, AND THE INDIANS IN THE OLD DAYS TURNED THEM INTO DUGOUT CANOES. CAN YOU UNDERSTAND THESE CONCEPTS, OR DID YOUR MAMA DROP YOU ON YOUR HEAD WHEN YOU WERE A BABY?
GSwift7
1.9 / 5 (9) Dec 21, 2011
Howhot, I respectfully ask you to read the article again. What they are talking about is the forest fire management strategy of cutting and spraying underbrush and small trees, so that if there is a fire, it is smaller and easier to control. The study is looking at what effect this will have on the overall ability of the forest to sequester carbon. They are proposing that thinning damages the forest's ability to sequester carbon. I think they are probably correct, and I was pointing out another reason, besides the reason they gave, that thinning will decrease the forest's ability to sequester carbon. Pirouette pointed out yet another reason that thinning will decrease a forest's ability to sequester carbon, though I wouldn't mind having an intelligent discussion with Pirouette about what he proposed, as I only partly agree with him.

Anyway, as small farms are dwindling in the US, forests are making a comeback accross the country. This is good.
GSwift7
1.9 / 5 (9) Dec 21, 2011
To Pirouette:

In the short term, I agree with you, but with the following caveat. New growth is a sink, but once a forest reaches max bio-density, the carbon intake balances out and it becomes very nearly carbon neutral, as a store rather than a significant sink. Unless old growth is cut down and replanted with saplings every 100-400 years or so, or nature does the same with a fire.
ubavontuba
1.4 / 5 (9) Dec 21, 2011
New growth is a sink, but once a forest reaches max bio-density, the carbon intake balances out and it becomes very nearly carbon neutral, as a store rather than a significant sink. Unless old growth is cut down and replanted with saplings every 100-400 years or so, or nature does the same with a fire.
I will disagree with this, to a degree, and as a basic premise I propose the following postulate:

The density of boreal forests (the world's largest terrestrial biome) is directly proportional to their long term ability to retain additional carbon.

This is because the dead vegetation tends to accumulate, often lasting much longer than the live vegetation which replaces it. It's retained so long, in fact, that it contributes poorly to the soil.

QUOTE:
"Fallen leaves and moss can remain on the forest floor for a long time in the cool, moist climate, which limits their organic contribution to the soil:"

http://en.wikiped...ga#Soils

More...
ubavontuba
1.8 / 5 (10) Dec 21, 2011
The biosphere appears to be booming, as a result of increased CO2 production. This has been known for some time, as seen here:

QUOTE:
"...net primary production increased 6% (3.4 petagrams of carbon over 18 years) globally."

http://www.scienc...abstract

and here:

QUOTE:
"...the low albedo of boreal forests is a positive climate forcing.

http://www.scienc...44.short

Here's some satellite data:

http://svs.gsfc.n...dex.html

There are lots of additional papers on it.

But the conclusion I draw is (generally speaking) forest NPP (carbon storage) is directly proportional to available CO2 in the atmosphere.
rubberman
5 / 5 (3) Dec 21, 2011
UVT, thanks for the links. Despite this "boom" of forest growth, PPM of CO2 are still rising 2-5 PPM annually, the earths systems cannot absorb it at the pace that it is entering the environment. In a warming climate, the boreal forests are the ones with the highest risk of wild fire due to those fallen leaves and scrub being subject to weeks of extended hot and dry weather in the summer, combined with their low albedo. I would agree with GS's conclusion regarding the carbon sink/carbon neutral nature of forests with respect to the max bio-density factor.
VD, hopefully the blanket analogy will help Dodds understand.
GSwift7
2 / 5 (8) Dec 21, 2011
ubavontuba:

This is because the dead vegetation tends to accumulate, often lasting much longer than the live vegetation


That agrees with what I said. The dead vegetation will also reach an equilibrium level depending on local conditions.
ubavontuba
1.9 / 5 (9) Dec 21, 2011
That agrees with what I said. The dead vegetation will also reach an equilibrium level depending on local conditions.
I don't think so. I see your concept more as an extremal hypothesis, than a reflection of what's currently occurring.

Eventually, the system might be maxed out, but according to forest statistics we've not reached it yet. You have to remember that as forests grow denser, they also tend to grow taller. Additionally, there's still plenty of room for them to spread out, and they're doing just that.

It's probably not a bottomless carbon sink, but it's certainly vast.

ubavontuba
1.9 / 5 (9) Dec 21, 2011
Despite this "boom" of forest growth, PPM of CO2 are still rising 2-5 PPM annually, the earths systems cannot absorb it at the pace that it is entering the environment.
But as the forests grow more abundant, their ability to absorb more carbon will increase, as there's more growth potential.

In a warming climate, the boreal forests are the ones with the highest risk of wild fire due to those fallen leaves and scrub being subject to weeks of extended hot and dry weather in the summer, combined with their low albedo.
This is indeed a problem. Catastrophic fire events are likely to increase in frequency as a result.

I would agree with GS's conclusion regarding the carbon sink/carbon neutral nature of forests with respect to the max bio-density factor.
I suppose there's a theoretical maximum carbon content to the terrestrial biome, but we're not even close to it. I'd suggest we'll run out of fossil fuels long before reaching it (isn't the biome where it came from?).
Pirouette
2 / 5 (7) Dec 21, 2011
Well, the continued growth of trees and the yearly dropping of their seeds ensure that, if left alone, forests do spread out farther afield, and the saplings that grow from the seeds continue the forest into other areas. When the logging companies come to cut down the old growth and haul the logs away to the lumber mills, the land owners then replant new saplings, and the process continues as CO2 and other nutrients are absorbed.
The old growth give up CO2 if alowed to decay naturally, but the loggers take them away for the purpose of using and turning the logs into useful products. It would be a travesty to try to prevent the process of manufacturing useful items from old growth trees just because they emit CO2 after being taken down. As I've said before, trees are a living organism, they are NOT fossil fuels, and should never be regarded as such by those who should know better.
Howhot
3.7 / 5 (3) Dec 22, 2011
As far as sequestration of CO2 in the forest, it is certainly a very large sink globally. I was thinking of another article about the desertification of some forest lands by changes in climate and the feed back mechanism that could cause. Like less of a CO2 sink, more CO2 from burning surface rubbish and that kind of thing. So yeah I was off topic from the article. It would be interesting to know if there was an increase in global CO2 levels when North Africa underwent desertification.

A tree is not coal (or oil or natural gas) while it is part of the biosphere and so can not be a sink for CO2 sequestration like coal. However, It can sink some CO2 temporarily in the 100 year time frames of the life of a tree and the 100 year life span as lumber too. And don't forget coal was once old forest material that was eventually was trapped.

GSwift7
1.9 / 5 (9) Dec 22, 2011
I think we seem to be talking accross terms. Let's define a handful of terms.

Sequestration: is when the carbon is taken out of the cycle. Carbon taken into a forest might be sequestered, but that is debatable depending on your frame of reference.

A Sink: is a place where carbon is being sequestered faster than it is being emitted.

A Source: is the opposite of a sink.

A Store: is a place where carbon has been sequestered. Stores can be either carbon neutral, a sink or a source. Most stores (such as a forest or the ocean) fluctuate between sink and source over time.

A forest is a store, as well as the soil under the forest. A forest takes in and releases carbon at different times. At night and in winter, a forst is a source. In the growing season in the daytime it is a sink. Typical boreal forest fire frequency is naturally around 400 years, for any given place, on average, over millenial time scales.
GSwift7
1.5 / 5 (8) Dec 22, 2011
So, by thinning, preventing forest fires, logging, etc. humans can change the balance of how strongly a forest is either a sink, source or neutral.

When a forest re-grows after being damaged or destroyed by people, you could say that it is a sink, but compared to geological time scales, it is just returning to the way it was before, so it could still be either a sink or a source in the long run, depending on a lot of factors. I don't think we know with much certainty how the current amount of forestation compares to the amount of forestation on the planet in other interglacial times. It is almost certain that we have a lot more forest now than we did during the ice ages though.

If the ocean, soil and forests did not reach their max carbon capacity relatively quickly (in geologic time) and achieve equilibrium between sink and source, then the world would either be choked with carbon or we wouldn't have enough in the atmosphere to support life. A permanent sink doesn't make sense.
GSwift7
1.6 / 5 (9) Dec 22, 2011
I suppose there's a theoretical maximum carbon content to the terrestrial biome, but we're not even close to it.


I think you need to stop guessing and do some reading. The majority of forest on the planet is boreal forest, in Canada and Russia. The majority of those have never been touched by man. They have all seen multiple generations of fully mature trees come and go. The soil there is also at maximum carbon content. The topsoil depth does not get any deeper than it is right now. In those cases, which represent the majority of forest on the planet, the carbon cycle is generally in equilibrium. The same is true for areas of untouched tropical rainforest. You might think that leaf-fall would build up endlessly, but it doesn't. It reaches a level were decomposition and consumption by organisms will be generally equal to the rate of deposition. If you have ever had a compost pile, you can see this effect in fast motion. The more you add, the faster it is consumed.
ubavontuba
1.6 / 5 (8) Dec 22, 2011
I think you need to stop guessing and do some reading.
Why don't you read my references?..Oh wait, it seems you did and then tried to claim the data as your own.

QUOTE my reference:
"The world's forests influence climate through physical, chemical, and biological processes that affect planetary energetics, the hydrologic cycle, and atmospheric composition. These complex and nonlinear forest-atmosphere interactions can dampen or amplify anthropogenic climate change." (...and so on)

QUOTE GSwift7:
"A forest is a store, as well as the soil under the forest. A forest takes in and releases carbon at different times. At night and in winter, a forst is a source. In the growing season in the daytime it is a sink." (...and so on)

Anyway, here's a cool photoblog which shows old growth forest density and area changes, over time, in the Yosemite area:

http://www.ridgel...ject.htm

(don't forget to page down to see the entire sequence)
Pirouette
1.8 / 5 (5) Dec 23, 2011
It is apparent that both GSwift7 and ubavontuba are both correct. Both cycles of sink, store and source, (usually in that order), plus the effects of the living and dead trees' cycles upon weather patterns and atmospheric differences in clean air or polluted air are all valid accounts of Natural forces combined with the unnatural that actually determine the fates of both air-breathers and CO2 sequesters. There must be a careful balance between Nature and unnatural forces in order to avoid the tipping point of either not enough CO2 that kills off trees and plants, or too much. that will kill off air-breathers. . . .(and you know who you are) :)
So, we have not come to a face-off of ideas, but a mutual agreement. I congratulate both of you. And I still stand by my belief that a coterie of scientists and doctors should make surprise visits to every major city and town in every country to accumulate pollution data and report it immediately to its headquarters, funded by the United Natio
GSwift7
1.9 / 5 (9) Dec 23, 2011
There must be a careful balance between Nature and unnatural forces in order to avoid the tipping point of either not enough CO2 that kills off trees and plants, or too much. that will kill off air-breathers. .


Yes, the system is elastic and self regulating. It resists any tipping point more and more strongly when harder forces are applied in the direction of a tipping point. Speed of change is critical, but plants are capable of adapting in months. They are extremely adaptable. You would need to be adaptable if you were rooted to the ground in one place your entire life. lol. Imagine never picking up your feet and living over 500 years? That's crazy.

We're having a really warm winter here in SC right now, for example. The flowers are blooming already, and the bees are back out too. Isn't nature amazing? Difficult to believe it's two days till Christmas with 75 F outside.

Merry Christmas to everyone, btw!!!!
Pirouette
2 / 5 (4) Dec 23, 2011
Merry Christmas to you, GSwift7
I will send a letter to the United Nations with a request for that which I mentioned about the surprise visits to all countries by scientists and doctors for the purpose of testing the environment for pollutants. One such doctor would need to be a heart and lung specialist.
kaasinees
3 / 5 (2) Dec 24, 2011
Yes, the system is elastic and self regulating.

See Gaia hypothesis. (no, it does not believe in a deity as you wrongly thought so before)

It resists any tipping point more and more strongly when harder forces are applied in the direction of a tipping point.

Wrong. It doesn't resist any tipping point. Some areas are able to adept to climate change due to abundance of water = more water uptake and release for cooling. Together with increased water evaporation makes more rainfall which is good for more cooling. These areas are pretty stable compared to the rest of the planet.
However in some areas where rainfall is not so straight forward you will see increased droughts. Plants will take more water for cooling and increase water evaporation until there is no more water left which is the tipping point, plants will die and become rare.
Other areas however will see increased floods perpetuating climate change.
GSwift7
1 / 5 (3) Dec 27, 2011
I forget who I was arguing with about the methane from ocean floor venting, due to global warming, but the head of the field research team got wind of the article you guys linked to. He contacted a reporter at the New York Times and they printed the correction to the article you guys linked to about the methane. Here's the quote from the NYT, from the field researchers (Semiletov and Shakhova):

We would first note that we have never stated that the reason for the currently observed methane emissions were due to recent climate change.

In fact, we explained in detail the mechanism of subsea permafrost destabilization as a result of inundation with seawater thousands of years ago.


LOL!! I wonder where NSF got their information? They also said:

source:

http://dotearth.b...oncerns/
Howhot
3 / 5 (2) Dec 27, 2011
That was me G7. Thanks for the link, it was very informative. The quote you have extracted is a little misleading in that the methane from subsea permafrost is very much effected by climate change and they say as much;

The rate at which the subsea permafrost is currently degrading largely depends on what state it was in when recent climate change appeared.


That implies there is a deep concern that the venting could be correlated to global temperature rise. A ominous feed back mechanism predicted in many climate change models.
Howhot
3 / 5 (2) Dec 27, 2011
That said, they do say that other monitoring systems have not seen a "signal" for methane or the feedback being activated by temperature rise yet. One possible issue is the model assumed for subsea permafrost methane release is temperature. The models predict release at 0C degrees, but the are seeing it at (minus) -1.2C, implying that the permafrost could be more sensitive to climate change than thought.