feedbacks, are they important?

[Old Rocks]

TC - Abstract - Uncertainties in the global temperature change caused by carbon release from permafrost thawing

Uncertainties in the global temperature change caused by carbon release from permafrost thawing

E. J. Burke1, I. P. Hartley2, and C. D. Jones1
1Met Office Hadley Centre, FitzRoy Road, Exeter, EX1 3PB, UK
2Geography, College of Life and Environmental Sciences, University of Exeter, Rennes Drive, Exeter, EX4 4RJ, UK

Abstract. Under climate change thawing permafrost will cause old carbon which is currently frozen and inert to become vulnerable to decomposition and release into the climate system. This paper develops a simple framework for estimating the impact of this permafrost carbon release on the global mean temperature (P-GMT). The analysis is based on simulations made with the Hadley Centre climate model (HadGEM2-ES) for a range of representative CO2 concentration pathways. Results using the high concentration pathway (RCP 8.5) suggest that by 2100 the annual methane (CH4) emission rate is 2–59 Tg CH4 yr−1 and 50–270 Pg C has been released as CO2 with an associated P-GMT of 0.08–0.36 °C (all 5th–95th percentile ranges). P-GMT is considerably lower – between 0.02 and 0.11 °C – for the low concentration pathway (RCP2.6). The uncertainty in climate model scenario causes about 50% of the spread in P-GMT by the end of the 21st century. The distribution of soil carbon, in particular how it varies with depth, contributes to about half of the remaining spread, with quality of soil carbon and decomposition processes contributing a further quarter each. These latter uncertainties could be reduced through additional observations. Over the next 20–30 yr, whilst scenario uncertainty is small, improving our knowledge of the quality of soil carbon will contribute significantly to reducing the spread in the, albeit relatively small, P-GMT

 

[Old Rocks]

AGW Observer

Permafrost carbon release could lead to significant warming even under less intensive emissions trajectories

Significant contribution to climate warming from the permafrost carbon feedback – MacDougall et al. (2012)

Abstract: “Permafrost soils contain an estimated 1,700 Pg of carbon, almost twice the present atmospheric carbon pool. As permafrost soils thaw owing to climate warming, respiration of organic matter within these soils will transfer carbon to the atmosphere, potentially leading to a positive feedback. Models in which the carbon cycle is uncoupled from the atmosphere, together with one-dimensional models, suggest that permafrost soils could release 7–138 Pg carbon by 2100 (refs 3, 4). Here, we use a coupled global climate model to quantify the magnitude of the warming generated by the feedback between permafrost carbon release and climate. According to our simulations, permafrost soils will release between 68 and 508 Pg carbon by 2100. We show that the additional surface warming generated by the feedback between permafrost carbon and climate is independent of the pathway of anthropogenic emissions followed in the twenty-first century. We estimate that this feedback could result in an additional warming of 0.13–1.69 °C by 2300. We further show that the upper bound for the strength of the feedback is reached under the less intensive emissions pathways. We suggest that permafrost carbon release could lead to significant warming, even under less intensive emissions trajectories.”

Citation: Andrew H. MacDougall, Christopher A. Avis & Andrew J. Weaver, Nature Geoscience, 2012, doi:10.1038/ngeo1573

 

[CrusaderFrank]

600,000 consecutive years of data from Vostok says you have it backwards, CO2 lags temperature

 

[RollingThunder]

600,000 consecutive years of data from Vostok says you have it backwards, CO2 lags temperature

That's just your ignorant and very retarded take on it, CrazyFruitcake. The scientists who study this say different. Even if you're too screwed up and brainwashed to tell the difference, most people know which one they'd trust to give them accurate information when it is between some anonymous nutjob on a debate forum or peer-reviewed scientific papers in top notch science journals.


[ame=http://www.youtube.com/watch?v=hWJeqgG3Tl8]Climate Denial Crock of the Week - The Temp leads Carbon Crock - YouTube[/ame]

 

[flacaltenn]

600,000 consecutive years of data from Vostok says you have it backwards, CO2 lags temperature

That's just your ignorant and very retarded take on it, CrazyFruitcake. The scientists who study this say different. Even if you're too screwed up and brainwashed to tell the difference, most people know which one they'd trust to give them accurate information when it is between some anonymous nutjob on a debate forum or peer-reviewed scientific papers in top notch science journals.

You're really a nasty little fairy ain'tcha Tink?

When you pounce like that before you engage your brain -- it really shows how little effort you put into this.. Frank was making a cogent point..

When the Arctic temps INCREASE, icy stuff melts and we do see GHG emission as a result --- These feedbacks ARE BY DEFINITION ----- an example of CO2 increases FOLLOWING temperature spikes. Really is the very nature of a feedback when the excitation is TEMPERATURE.

Even that Shakun 2012 pile you laid on us DEPENDS on an "unspecific" INITIAL INCREASE in temperature to start liberating CO2 from the frozen ICE age tundra...

 

[RollingThunder]

600,000 consecutive years of data from Vostok says you have it backwards, CO2 lags temperature

That's just your ignorant and very retarded take on it, CrazyFruitcake. The scientists who study this say different. Even if you're too screwed up and brainwashed to tell the difference, most people know which one they'd trust to give them accurate information when it is between some anonymous nutjob on a debate forum or peer-reviewed scientific papers in top notch science journals.

You're really a nasty little fairy ain'tcha Tink?

You're a massively retarded little piece of shit ain'tcha fecalhead?

When you pounce like that before you engage your brain -- it really shows how little effort you put into this.. Frank was making a cogent point..

CrazyFruitcake's specious 'points' only seem "cogent" to you because you're as retarded as he is.

When the Arctic temps INCREASE, icy stuff melts and we do see GHG emission as a result --- These feedbacks ARE BY DEFINITION ----- an example of CO2 increases FOLLOWING temperature spikes. Really is the very nature of a feedback when the excitation is TEMPERATURE.

Even that Shakun 2012 pile you laid on us DEPENDS on an "unspecific" INITIAL INCREASE in temperature to start liberating CO2 from the frozen ICE age tundra...

Increased CO2 levels in the atmosphere cause warming. That's a fact based on the laws of physics and verified by many decades of observation of the real world. It doesn't really matter if at times in the past other influences (warming from natural cycles, extreme vulcanism, etc.) caused the initial increase in CO2 levels. The point remains that the increased CO2 was the main cause of the subsequent warming. Currently mankind is adding massive quantities of CO2 to the atmosphere every year and that extra CO2 is producing the current abrupt warming trend.

 

[westwall]

TC - Abstract - Uncertainties in the global temperature change caused by carbon release from permafrost thawing

Uncertainties in the global temperature change caused by carbon release from permafrost thawing

E. J. Burke1, I. P. Hartley2, and C. D. Jones1
1Met Office Hadley Centre, FitzRoy Road, Exeter, EX1 3PB, UK
2Geography, College of Life and Environmental Sciences, University of Exeter, Rennes Drive, Exeter, EX4 4RJ, UK

Abstract. Under climate change thawing permafrost will cause old carbon which is currently frozen and inert to become vulnerable to decomposition and release into the climate system. This paper develops a simple framework for estimating the impact of this permafrost carbon release on the global mean temperature (P-GMT). The analysis is based on simulations made with the Hadley Centre climate model (HadGEM2-ES) for a range of representative CO2 concentration pathways. Results using the high concentration pathway (RCP 8.5) suggest that by 2100 the annual methane (CH4) emission rate is 2–59 Tg CH4 yr−1 and 50–270 Pg C has been released as CO2 with an associated P-GMT of 0.08–0.36 °C (all 5th–95th percentile ranges). P-GMT is considerably lower – between 0.02 and 0.11 °C – for the low concentration pathway (RCP2.6). The uncertainty in climate model scenario causes about 50% of the spread in P-GMT by the end of the 21st century. The distribution of soil carbon, in particular how it varies with depth, contributes to about half of the remaining spread, with quality of soil carbon and decomposition processes contributing a further quarter each. These latter uncertainties could be reduced through additional observations. Over the next 20–30 yr, whilst scenario uncertainty is small, improving our knowledge of the quality of soil carbon will contribute significantly to reducing the spread in the, albeit relatively small, P-GMT

An entire religion based on computer models....you guys crack me up.

 

[Old Rocks]

Now Walleyes, were you to actually read the article, they are trying to determine the feedback that they will get to from thawing of the permafrost. They do so by taking known data points and extrapolating differant emission scenerios.

But then again, trying to use presently known data to extrapolate future events is application of science. Whether you are estimating the creep of a hillside or the emissions from permafrost. It is called science, something you are obviously unfamiliar with.

 

[RollingThunder]

An entire religion based on computer models....you guys crack me up.

And we get a big chuckle watching a cult based on reality denial (and full of clueless retards) melt down as reality wins and the cultic myths go down in flames.

 

[westwall]

Now Walleyes, were you to actually read the article, they are trying to determine the feedback that they will get to from thawing of the permafrost. They do so by taking known data points and extrapolating differant emission scenerios.

But then again, trying to use presently known data to extrapolate future events is application of science. Whether you are estimating the creep of a hillside or the emissions from permafrost. It is called science, something you are obviously unfamiliar with.

They are using models, based on other models, that use data that was generated by other models. There is very little real observed science there olfraud. When that changes I will begin to pay attention to what they have to say. Of course their models need to do better than a Random Walk as well, aaaaannnd that will no doubt take a reaally long time, but hey, at least it's a MEASURABLE benchmark, unlike everything else they spew out.

 

[westwall]

An entire religion based on computer models....you guys crack me up.

And we get a big chuckle watching a cult based on reality denial (and full of clueless retards) melt down as reality wins and the cultic myths go down in flames.

Sure thing buckwheat, we're not the ones falsifying data or denying publication to scientists who's data disagrees with our pre-conceived ideas. But hey, keep on keepin on, you help us out every time you open your trap.

And for that we thank you!

 

[CrusaderFrank]

[ame=http://www.youtube.com/watch?v=luURyH9fzhk]Ultimate Guitar Feedback Lesson - YouTube[/ame]

 

[flacaltenn]

Now Walleyes, were you to actually read the article, they are trying to determine the feedback that they will get to from thawing of the permafrost. They do so by taking known data points and extrapolating differant emission scenerios.

But then again, trying to use presently known data to extrapolate future events is application of science. Whether you are estimating the creep of a hillside or the emissions from permafrost. It is called science, something you are obviously unfamiliar with.

They are using models, based on other models, that use data that was generated by other models. There is very little real observed science there olfraud. When that changes I will begin to pay attention to what they have to say. Of course their models need to do better than a Random Walk as well, aaaaannnd that will no doubt take a reaally long time, but hey, at least it's a MEASURABLE benchmark, unlike everything else they spew out.

You can get a lot of mileage out of models.. Look what James Cameron did in Avatar.. He could create any reality his creative heart desired..

I've worked with neural nets, adaptive learning networks and expert system designs. All design to TRAIN ON real world data.. The problem here is the models are built to reproduce the nebulous and frankly meaningless "Global Annual Mean Surface Temp".. That's NOT a "climate model". Or in other cases, they are isolating other trivial dependent variables that are a small part of the understanding of the larger physical system.

And if you TRAIN ON a limited trivial data set like mean annual surface temp, you really have no idea of the forecasting validity. Even IF you manage to 'hindcast' by a couple decades.. Not truely impressive as the answer to everything...

 

[westwall]

Now Walleyes, were you to actually read the article, they are trying to determine the feedback that they will get to from thawing of the permafrost. They do so by taking known data points and extrapolating differant emission scenerios.

But then again, trying to use presently known data to extrapolate future events is application of science. Whether you are estimating the creep of a hillside or the emissions from permafrost. It is called science, something you are obviously unfamiliar with.

They are using models, based on other models, that use data that was generated by other models. There is very little real observed science there olfraud. When that changes I will begin to pay attention to what they have to say. Of course their models need to do better than a Random Walk as well, aaaaannnd that will no doubt take a reaally long time, but hey, at least it's a MEASURABLE benchmark, unlike everything else they spew out.

You can get a lot of mileage out of models.. Look what James Cameron did in Avatar.. He could create any reality his creative heart desired..

I've worked with neural nets, adaptive learning networks and expert system designs. All design to TRAIN ON real world data.. The problem here is the models are built to reproduce the nebulous and frankly meaningless "Global Annual Mean Surface Temp".. That's NOT a "climate model". Or in other cases, they are isolating other trivial dependent variables that are a small part of the understanding of the larger physical system.

And if you TRAIN ON a limited trivial data set like mean annual surface temp, you really have no idea of the forecasting validity. Even IF you manage to 'hindcast' by a couple decades.. Not truely impressive as the answer to everything...

All of what you say is very true. Unfortunately for them they can't even 'hindcast' two days back. Their models are so poor they are incapable of recreating what we know occured with perfect knowledge of all the variables invovled.

Pathetic.

 

[Oddball]

Yet, somehow or another, the opposing feedback from increased growth of vegetation, which absorbs CO2, gets minimized if not marginalized?

Likewise, the feedback of more atmospheric water vapor, which produces more cloud cover, which reflects more solar radiation, gets poo-pooed?

Pffffft!

 

[Old Rocks]

Yet, somehow or another, the opposing feedback from increased growth of vegetation, which absorbs CO2, gets minimized if not marginalized?

Likewise, the feedback of more atmospheric water vapor, which produces more cloud cover, which reflects more solar radiation, gets poo-pooed?

Pffffft!

Here, learn something if you are capable of that;

http://pielkeclimatesci.files.wordpress.com/2009/10/r-309.pdf

spring snowmelt and near-surface air temperatures

John E. Strack,1 Roger A. Pielke Sr.,1 and Glen E. Liston2
Received 23 August 2006; revised 9 April 2007; accepted 3 May 2007; published 2 November 2007.

[1] Invasive shrubs and soot pollution both have the potential to alter the surface energy
balance and timing of snow melt in the Arctic. Shrubs reduce the amount of snow lost
to sublimation on the tundra during the winter leading to a deeper end-of-winter
snowpack. The shrubs also enhance the absorption of energy by the snowpack during the
melt season by converting incoming solar radiation to longwave radiation and sensible
heat. Soot deposition lowers the albedo of the snow, allowing it to more effectively absorb
incoming solar radiation and thus melt faster. This study uses the Colorado State
University Regional Atmospheric Modeling System version 4.4 (CSU-RAMS 4.4),
equipped with an enhanced snow model, to investigate the effects of shrub encroachment
and soot deposition on the atmosphere and snowpack in the Kuparuk Basin of Alaska
during the May–June melt period. The results of the simulations suggest that a complete
invasion of the tundra by shrubs leads to a 2.2
C warming of 3 m air temperatures and a
108 m increase in boundary layer depth during the melt period. The snow-free date
also occurred 11 d earlier despite having a larger initial snowpack. The results also show
that a decrease in the snow albedo of 0.1, owing to soot pollution, caused the snow-free
date to occur 5 d earlier. The soot pollution caused a 1.0
C warming of 3 m air
temperatures and a 25 m average deepening of the boundary layer.

 

[Oddball]

Shrubs aren't anywhere near as effective a CO2 sink as are grasslands....Which cover a vastly wider range of the planet.

Speaking of shutting one's yap and learning something.

 

[Old Rocks]

Shrubs aren't anywhere near as effective a CO2 sink as are grasslands....Which cover a vastly wider range of the planet.

Speaking of shutting one's yap and learning something.

Are you really that stupid? Your initial post was stating that the growth of vegitation would increase the uptake of CO2 and decrease the warming. I pointed out a study that showed that the increased vegitation in the Arctic, which is an increase in shrubs, is actually increasing the warming of the Arctic.

 

[Oddball]

Your continued clinging to the notion that increased CO2 produces warming, despite the confirmed ice core evidence that CO2 is a lagging indicator, is your problem.

Point being and fact remaining that there are uncountable natural feedback phenomena that ultimately operate to offset one another.

The planet could, figuratively, squish all of our asses rolling over in its sleep and wouldn't know the difference....Get over yourself.