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Ned W

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Re: Arctic Methane Release
« Reply #200 on: April 17, 2015, 11:53:34 AM »
Ned W,

When Earth System Model scientists publish papers they generally assume that the readers know that climate sensitivity parameters such as ECS, TCR, or TCRE are emergent values based on the global mean temperature rise projections as a function of the radiative forcing input. 

Spare me the lecture, please.  I am fully aware that CS is an emergent property of models.  But the paper you linked to does not have any time-dependent change in CO2 and does not say anything about CS.  The graph you cite merely shows that for a given fixed CO2 concentration the higher-resolution model settles in at a slightly higher average T than a lower resolution model.  That does not mean that the higher model will respond to a change in CO2 by producing a larger change in T.   

You claimed that this paper was evidence that climate sensitivity is "high" and "non-linear".  The paper shows no such thing at all. 


GeoffBeacon

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Re: Arctic Methane Release
« Reply #201 on: April 17, 2015, 02:00:06 PM »
NedW

Quote
The graph you cite merely shows that for a given fixed CO2 concentration the higher-resolution model settles in at a slightly higher average T than a lower resolution model.
  and
 
Quote
You claimed that this paper was evidence that climate sensitivity is "high" and "non-linear".  The paper shows no such thing at all.

What about saying
Quote
the paper suggests that calculated climate sensitivities will be found to be higher when models ar run with higher resolution
?
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Ned W

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Re: Arctic Methane Release
« Reply #202 on: April 17, 2015, 02:17:14 PM »
Geoff, does the paper actually suggest that?

Consider a situation where a model is run at lower and higher resolutions, and at various CO2 forcings F1, F2, F3.  It's possible that in each case 1, 2, 3, the higher resolution model produces an average temperature that's 0.8 C warmer than the lower-resolution model.  The higher resolution version looks "hotter" but its climate sensitivity is the same.

Now it's entirely possible that other research, elsewhere, suggests that across a wide variety of models, running the models at higher resolution consistently leads to a higher estimate of ECS.  That would be interesting.  But this particular paper doesn't say that.  It doesn't even say that for this one model (CESM) improved resolution leads to increased sensitivity.  It says nothing at all about climate sensitivity, as far as I can tell.

crandles

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Re: Arctic Methane Release
« Reply #203 on: April 17, 2015, 02:47:37 PM »

Consider a situation where a model is run at lower and higher resolutions, and at various CO2 forcings F1, F2, F3.  It's possible that in each case 1, 2, 3, the higher resolution model produces an average temperature that's 0.8 C warmer than the lower-resolution model.  The higher resolution version looks "hotter" but its climate sensitivity is the same.

If it simply 'looks "hotter" ', what happens when you run a hindcast to see if it does well enough before running a hindcast, you adjust both to a best fit temperature and continue making such adjustments to any forecasts produced. That eliminates such a 'looks "hotter" ' difference.

Even if you did have cases Res 1, Res 2, and Res 3 where the sensitivities did increase with higher resolution, while suggestive, it wouldn't rule out even higher resolution Res 4 producing lower sensitivity.

From that paper alone we just don't know whether sensitivity is higher, lower or the same.

AbruptSLR

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Re: Arctic Methane Release
« Reply #204 on: April 17, 2015, 02:58:58 PM »
From that paper alone we just don't know whether sensitivity is higher, lower or the same.

While I concur that this one paper by itself is not proof of anything; however, there are multiple lines of other evidence & I firmly believe that we need to maintain a margin of error when the future of society (and nature) is on the line.
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jai mitchell

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Re: Arctic Methane Release
« Reply #205 on: April 17, 2015, 08:02:23 PM »
 ::)

I did not see any mention of aerosols in their paper.  So I guess they are looking at a response sans aerosols?  If so then this is not relevant to our discussion of real life.  It is clear that the effect of aerosol impacts in the arctic are producing about -10Watts per meter squared average daily forcing in the region.  The loss of these aerosols will produce a complete arctic sea ice melt out.

In other words, if all human activity suddenly ceased.  We would immediately experience a full summer sea ice melt out.  With intense regional warming and permafrost destabilization. 

We may get to see the range of these impacts this melt season as China is experiencing a slowdown of their economy and has stalled coal consumption as well as initiated the beginnings of pollution regulation which will become increasingly significant to the earth system dynamics.
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Ned W

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Re: Arctic Methane Release
« Reply #206 on: April 17, 2015, 08:50:46 PM »
::)

I did not see any mention of aerosols in their paper. 

Which paper?  The one that the past few comments are referring to (about running a particular climate model at lower vs higher resolution)?  Or one that was discussed earlier?

The CESM study that ASLR linked to most definitely includes aerosols.  And there is no particular "response" since it's not looking at any kind of change or forcing.  It's just looking at how well the model can reproduce the existing climate system circa 2000.

AbruptSLR

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Re: Arctic Methane Release
« Reply #207 on: April 18, 2015, 12:06:25 AM »
Yes; the CESM-H run included aerosols (and all other non-CO₂ GHGs); however, it was run for 100-years (see extracted summary below), and while there are questions of spin-up and model bias, it is a projection if the world had stopped emitting CO₂ at 367ppm.  However, to get a full ensemble projection we will likely need to wait another 2.5 years when the first phase of the ACME project ends)

http://onlinelibrary.wiley.com/doi/10.1002/2014MS000363/full

Extracted Summary:
"A new high-resolution CESM simulation has been performed for 100 years, the longest such simulation with CAM5. The main highlights of the run are as follows:
1.   Equatorial Pacific SST biases are small (mostly <0.2°C), and globally the SST bias relative to observations is quite low compared to a standard resolution case.
2.   The power spectrum of Niño3.4 SST time series reveals that the frequency and amplitude of ENSO is comparable to observations, with much less variance than previous CESM/CCSM runs. The typical generation and decay of El-Niño events compares well with the observed record, but the La-Niña events do not show the observed second-year reemergence.
3.   There is a notably small SST bias in the equatorial Atlantic where a realistic cold tongue in the eastern basin develops in JJA and the ITCZ keeps mostly north of the Equator. Most climate models (including the CMIP5 generation and CCSM4) have a weak cold tongue or even a reversal of the zonal SST gradient. In this case, much of the improvement is also seen in the lower-resolution version of the model indicating a fundamental change from CCSM4 to CESM.
4.   In the ocean, the model eddy field is very rich and comparable to observations in terms of SSH variability: however the SST variability is too high. Ocean fronts are quite well represented: long-standing issues of the Gulf Stream path overshooting at Cape Hatteras and being too zonal in its extension still exist, but the consequent SST biases are considerably reduced compared to standard resolution models.
5.   A consequence of having strong SST gradients is that the overlying atmospheric boundary layer and storm track is modified, such that some of the strongest near-surface wind variability in the Globe occurs over the warm side of ocean fronts. In addition, huge amounts of heat are passed from ocean to atmosphere as cold winter continental air passes over western boundary currents. The climatological latent heat flux is, however, too strong over the Gulf Stream in the coupled model. Comparison with an atmosphere-only model reveals that the SST bias of the coupled model leads to the error.
6.   Mesoscale Convective Systems over the Rocky Mountains, which contribute to many of the important summertime weather events in the central U.S. are also seen in this simulation, but tend to occur earlier in the year, in spring, and have slower propagation speeds than most observed systems.
7.   In common with some previous high-resolution runs [e.g., McClean et al., 2011; Sakamoto et al., 2012], Tropical Cyclones are permitted. The tracks of these extreme events are somewhat realistic except for a striking lack of storms in the N. Atlantic and E. Pacific basins, whilst there are too many strong systems in the western Pacific.
8.   The substantial overestimation of Southern Hemisphere summer sea-ice seen in previous CCSM/CESM models is not seen; however, there is a general underestimation of summer sea ice in both high-resolution and standard resolution CESM in the perpetual year 2000 conditions.
Despite these improvements, some limitations of the model simulations persist, such as substantial deep ocean model drift at both high and standard resolutions, excessive precipitation in the ITCZ and wind stress in the extratropical storm tracks, and an overdiffuse Equatorial thermocline. Current model development with CESM is aiming to address these issues.
Current and future plans with these simulations include (i) the analysis of Kuroshio Extension variability on interannual to decadal time scales, and the atmospheric circulation response, (ii) investigation of possible compensation between ocean eddy heat transport and atmosphere heat transport, (iii) Southern Ocean variability, including response of the ocean to changing wind stress in a high-resolution coupled system, (iv) ocean near-inertial wave response to strong winds, (v) relationship of extreme events to large-scale modes of variability, (vi) analysis of Tropical Atlantic climate, and (vii) improvement of regridding of winds onto coastal ocean cells for upwelling studies. In addition, different resolution models are being analyzed (including one with 0.25° resolution in atmosphere, 1° in ocean) to more clearly distinguish the role of resolving ocean features versus resolving atmosphere features in the model improvements seen in CESM-H."
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jai mitchell

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Re: Arctic Methane Release
« Reply #208 on: April 18, 2015, 12:21:07 AM »
what do you suppose their 90-year surface temperature response would be if they allowed anthropogenic aerosol forcing to go to zero?  Would it be more than the 1.2C that they modeled? how much more?   This is a policy-relevant question since the necessary goal of zero emissions correlates with a significant reduction in aerosol forcing parameters.   
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AbruptSLR

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Re: Arctic Methane Release
« Reply #209 on: April 18, 2015, 03:59:54 AM »
what do you suppose their 90-year surface temperature response would be if they allowed anthropogenic aerosol forcing to go to zero?  Would it be more than the 1.2C that they modeled? how much more?   This is a policy-relevant question since the necessary goal of zero emissions correlates with a significant reduction in aerosol forcing parameters.

In my prior post I made a misstatement, in that the CESM - H run did not stop CO2 emissions at the nominally 2000 value of 267ppm, but rather that assumed that the CO2 emissions dropped at that point to the same level as that absorbed by the Earth Systems, and they then held all of the other GHGs and aerosol concentrations in the atmosphere also at their nominal 2000 level.  I do not know what would happen if the aerosol levels were allowed to drop below their nominal 2000 concentrations, but I imagine that the global mean temperature rise projected (not predicted) by the run would have been higher than the extant run showed.
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GeoffBeacon

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Re: Arctic Methane Release
« Reply #210 on: April 18, 2015, 10:22:09 AM »
NedW ... just a small bit of semantics. You ask

Quote
Geoff, does the paper actually suggest that?

That depends whether you insist that "suggest" means "explicitly suggest" . i.e. by writing the words "This suggests that...". That wasn't my meaning.

Perhaps I will go to that public lecture on Wittgenstein after all.
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AbruptSLR

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Re: Arctic Methane Release
« Reply #211 on: April 18, 2015, 06:19:45 PM »
NedW ... just a small bit of semantics. You ask

Quote
Geoff, does the paper actually suggest that?

That depends whether you insist that "suggest" means "explicitly suggest" . i.e. by writing the words "This suggests that...". That wasn't my meaning.

Perhaps I will go to that public lecture on Wittgenstein after all.

Geoff,

As anthropogenic climate change is specifically due human behavior it seem very appropriate to attend a public lecture on Wittgenstein (a philosopher).  Denalists tend to treat the IPCC process as some type of business negotiation [e.g. "What's mine is mine, what's yours is negotiable"]; rather than as a process of discovering non-negotiable natural responses to anthropogenic radiative forcing input.  In this regards, it seems to me that denalists [like Nic Lewis, etc.] frequently carefully craft papers on climate sensitivity so that they are incomplete/biased but can survive peer review in order to inappropriately add more references citing low climate sensitivity as the denalists know that all references are given equal weight when determining the climate sensitivity (TCRE) used to calculate the Carbon Budget that influences policy makers.

In the future, I hope that computer programs such as ACME (& CESM-H can be considered a test trial to help guide the ACME refinement process) can give sufficiently accurate projections that the IPCC can base their recommendations to policy makers directly on the temperature projections form such state-of-the-art Earth System Models [which of course during their spin-up process would need to match past observed paleo responses as well as better calibrated instrument observations {e.g. China's projected reduction in aerosols should allow from a much better understanding/calibration of the negative radiative forcing from this masking factor by 2030}].

Best,
ASLR

Edit: As my last posting of the attached CESM-H 10-year average global mean surface temperature change plot was rather blurry (due to my work schedule), I re-post a slightly less blurry version here, and I note that questions of model bias and spin-up aside, this plot indicates that it is possible that society has already exceeded [as the plot shows a potential 1.2 C {due to stabilizing at 367ppm CO2} of temperature rise on top of the 0.8C temperature rise extant at 2000] our carbon budget; indicating that stabilizing at 440ppm CO2 at some point in the future could very likely be inadvisable, which was the point that I was making in my Reply #193.
« Last Edit: April 18, 2015, 07:43:40 PM by AbruptSLR »
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jai mitchell

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Re: Arctic Methane Release
« Reply #212 on: April 18, 2015, 08:16:46 PM »


Quote
if the aerosol levels were allowed to drop below their nominal 2000 concentrations, but I imagine that the global mean temperature rise projected (not predicted) by the run would have been higher than the extant run showed.

according to the PIK Postdam RCP scenario data group  http://www.pik-potsdam.de/~mmalte/rcps/

total anthropogenic forcing in 2000 is 1.84 Watts per meter squared but total greenhouse gas forcing is 2.65 watts per meter squared so anthropogenic aerosols account for at least 30% reduction in the modeled results (probably more since anthropogenic black carbon is a positive forcing factor).
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Ned W

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Re: Arctic Methane Release
« Reply #213 on: April 19, 2015, 12:55:36 AM »
NedW ... just a small bit of semantics. You ask

Quote
Geoff, does the paper actually suggest that?

That depends whether you insist that "suggest" means "explicitly suggest" . i.e. by writing the words "This suggests that...". That wasn't my meaning.

OK, whatever.  The paper does not say that "calculated climate sensitivities will be found to be higher when models ar run with higher resolution" and, also, the paper does not suggest or imply or otherwise formally or informally lead one to expect that calculated climate sensitivities will be found to be higher when models are run with higher resolution.

The high-resolution model run ends up at a certain temperature, with a certain radiative forcing from CO2.  But there is no way to tell from this single run of the model how different temperature would be at a different forcing.  The model drift in the first half of the time series does not tell you what ASLR thinks it is telling you.

Ned W

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Re: Arctic Methane Release
« Reply #214 on: April 19, 2015, 01:08:59 AM »
the plot shows a potential 1.2 C {due to stabilizing at 367ppm CO2} of temperature rise on top of the 0.8C temperature rise extant at 2000    [...]

No it doesn't. 

Quote
which of course during their spin-up process would need to match past observed paleo responses

The spin-up period for climate models is not about reproducing past history.  It's about getting the model to stabilize in a reasonably realistic configuration before proceeding with the actual simulation.  Model conditions during the spin-up period are probably going to be quite unrealistic when compared to any real climate, paleo or not.

jai mitchell

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Re: Arctic Methane Release
« Reply #215 on: April 19, 2015, 01:38:34 AM »
the plot shows a potential 1.2 C {due to stabilizing at 367ppm CO2} of temperature rise on top of the 0.8C temperature rise extant at 2000    [...]

No it doesn't. 

Quote
which of course during their spin-up process would need to match past observed paleo responses

The spin-up period for climate models is not about reproducing past history.  It's about getting the model to stabilize in a reasonably realistic configuration before proceeding with the actual simulation.  Model conditions during the spin-up period are probably going to be quite unrealistic when compared to any real climate, paleo or not.

current globally averaged temperature is 287.15 (or so)  how does the model run output not show additional warming from current temperatures?
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AbruptSLR

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Re: Arctic Methane Release
« Reply #216 on: April 19, 2015, 02:38:13 AM »

The spin-up period for climate models is not about reproducing past history.  It's about getting the model to stabilize in a reasonably realistic configuration before proceeding with the actual simulation.  Model conditions during the spin-up period are probably going to be quite unrealistic when compared to any real climate, paleo or not.

While it is true that during the spin-up period that the projected temperatures should not accurately track the observed record, nevertheless, the standard CESM run was spun-up & in equilibrium by 2000, and prior to 2014 the CESM-H run was already matching numerous observed observations better than the CESM-S run (just look at the paper).  This clearly indicates to me that the equilibrium condition of the CESM-H run is reasonable (but will errors as all models have) and likely more accurate than the AR5 projections (as the CESM is one of the CMIP5 contributing programs).  Therefore, while I am willing to wait for the end of the first phase of the ACME program (in another 2.5 years) before expecting policy makers to take note; I do find this paper to present findings for increasing levels of concern that climate sensitivity may well be greater than projected by CMIP5.
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crandles

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Re: Arctic Methane Release
« Reply #217 on: April 19, 2015, 10:31:27 AM »

current globally averaged temperature is 287.15 (or so)  how does the model run output not show additional warming from current temperatures?

The model run simply shows that the atmosphere of the model is out of balance with the ocean of the model at the start of the run. If it was in balance before the run started then with no changes to GHG over the period you would expect a steady global temperature.

By the end of the run it is much closer to being in balance.

(Year 2000 climate isn't in balance either we have had 0.8C warming and if GHG levels held steady now we would expect close to 2C warming. So a 1.2C increase suggest the model is about as out of balance as our year 2000 situation was.)

AbruptSLR

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Re: Arctic Methane Release
« Reply #218 on: April 19, 2015, 10:40:43 AM »
While no model is truly correct, as an example of how well CESM-H performed can be seen in the attached image (with the following caption) comparing observed vs CESM-H vs CESM-S annual mean SST along the Equatorial Pacific Ocean.

Caption for Figure 7: "(a) Annual mean SST along the Equator, Pacific Ocean. Black line: CESM-H, red line: Reynolds et al. [2002] climatology. (b) As Figure 7a but for CESM-S. Data are averaged between latitudes 1.5°S and 1.5°N. (c) Seasonal cycle of SST at equator from (left) Reynolds et al. climatology, (middle) CESM-H, and (right) CESM-S."

See:
http://onlinelibrary.wiley.com/doi/10.1002/2014MS000363/full

Furthermore, outputs from both the High Resolution and the Standard (including spin-up) CESM runs can be found here:

https://www.earthsystemgrid.org/dataset/ucar.cgd.asd.output.html

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jai mitchell

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Re: Arctic Methane Release
« Reply #219 on: April 19, 2015, 07:35:24 PM »

current globally averaged temperature is 287.15 (or so)  how does the model run output not show additional warming from current temperatures?

The model run simply shows that the atmosphere of the model is out of balance with the ocean of the model at the start of the run. If it was in balance before the run started then with no changes to GHG over the period you would expect a steady global temperature.

By the end of the run it is much closer to being in balance.

(Year 2000 climate isn't in balance either we have had 0.8C warming and if GHG levels held steady now we would expect close to 2C warming. So a 1.2C increase suggest the model is about as out of balance as our year 2000 situation was.)

well, it BETTER have the oceans out of balance with the atmosphere!  Ricke and Caldeira showed that there is a 10 year temperature response time to a slug of emissions, primarily due to thermal inertia.  With a current (2015) top of atmosphere energy imbalance of about 1.2 Watts per meter squared (twice the Hansen and Sato 2007 mean estimate) and with between 30% and 50% of total forcing being offset by anthropogenic aerosols there is significantly more warming locked in, as you suggest with your 2C estimate, however, your estimate is the pure CO2 forcing based on a projected median 3.0C ECS and does not include albedo, carbon cycle, frozen soil and ocean acidification reductions in DMS production, all of which have significant positive inputs.

as a side note, have you seen

this V V V V  (source: http://ocean.dmi.dk/arctic/meant80n.uk.php  )

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AbruptSLR

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Re: Arctic Methane Release
« Reply #220 on: April 19, 2015, 11:41:13 PM »
With a hat-tip to jdallen & wili from their recent posts in the Arctic Wildfire thread, the following linked articles discuss early & severe wildfire raging in Siberia that will clearly accelerate the degradation of the permafrost effected by such wildfires.

https://robertscribbler.wordpress.com/2015/04/14/unprecedented-early-start-to-perma-burn-fire-season-deadly-wildfires-rage-through-siberia-on-april-12/

http://www.themoscowtimes.com/arts_n_ideas/news/article/russian-ecologists-warn-summer-could-see-repeat-of-devastating-2010-wildfires–or-worse/519338.html

http://www.king5.com/story/weather/2015/04/18/hazy-seattle-sky-is-from-siberia-wildfires/25998639/

Edit: For what it is worth, I note that the last time there was a comparable scale of wildfires in Russia was during the 2010 El Nino year; and now in 2015 we are projected to have a possibly stronger El Nino event (which can affect weather conditions in Russia).
« Last Edit: April 20, 2015, 04:39:32 PM by AbruptSLR »
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jai mitchell

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Re: Arctic Methane Release
« Reply #221 on: April 20, 2015, 10:58:43 PM »
http://www.carbonbrief.org/blog/2015/04/tiny-marine-plants-could-amplify-arctic-warming-by-20-percent-new-study-finds/

Tiny marine plants could amplify Arctic warming by 20%, new study finds

Quote
So how could algal blooms intensify sea ice decline? As the Arctic warms up and the sea ice melts, more sunlight can penetrate into the ocean surface, triggering more growth in the algae.

With more microalgae floating around in the surface waters of the ocean, they absorb an increasing amount of the sun's energy, which causes the water to warm up. A warmer ocean means more sea ice melts, boosting algal growth even further, and creating a positive feedback loop.

paper here:  Amplified Arctic warming by phytoplankton under greenhouse warming
http://www.pnas.org/content/early/2015/04/14/1416884112.abstract

Park et. al. (2015)

abstract:  One of the important impacts of marine phytoplankton on climate systems is the geophysical feedback by which chlorophyll and the related pigments in phytoplankton absorb solar radiation and then change sea surface temperature. Yet such biogeophysical impact is still not considered in many climate projections by state-of-the-art climate models, nor is its impact on the future climate quantified. This study shows that, by conducting global warming simulations with and without an active marine ecosystem model, the biogeophysical effect of future phytoplankton changes amplifies Arctic warming by 20%. Given the close linkage between the Arctic and global climate, the biologically enhanced Arctic warming can significantly modify future estimates of global climate change, and therefore it needs to be considered as a possible future scenario.
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AbruptSLR

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Re: Arctic Methane Release
« Reply #222 on: April 21, 2015, 11:35:50 PM »
The linked reference provides field evidence that shifts in the location of the West Spitsbergen Current near Svalbard can abruptly reduce the amount of methane (released from seafloor hydrate decomposition) consumed by methanotrophic bacteria, thus leaving larger amounts of methane in the water column.  If similar events occur in shallow Arctic waters (now or in the future) then surplus methane in the water column could be released to the atmosphere.

Steinle, L., C. A. Graves, T. Treude, B. Ferré, A. Biastoch, I. Bussmann, C. Berndt, S. Krastel, R. H. James, E. Behrens, C. W. Böning, J. Greinert, C.-J. Sapart, M. Scheinert, S. Sommer, M. F. Lehmann, H. Niemann (2015), "Water column methanotrophy controlled by a rapid oceanographic switch", Nature Geoscience, DOI 10.1038/ngeo2420

http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo2420.html

Abstract: "Large amounts of the greenhouse gas methane are released from the seabed to the water column, where it may be consumed by aerobic methanotrophic bacteria. The size and activity of methanotrophic communities, which determine the amount of methane consumed in the water column, are thought to be mainly controlled by nutrient and redox dynamics. Here, we report repeated measurements of methanotrophic activity and community size at methane seeps west of Svalbard, and relate them to physical water mass properties and modelled ocean currents. We show that cold bottom water, which contained a large number of aerobic methanotrophs, was displaced by warmer water with a considerably smaller methanotrophic community within days. Ocean current simulations using a global ocean/sea-ice model suggest that this water mass exchange is consistent with short-term variations in the meandering West Spitsbergen Current. We conclude that the shift from an offshore to a nearshore position of the current can rapidly and severely reduce methanotrophic activity in the water column. Strong fluctuating currents are common at many methane seep systems globally, and we suggest that they affect methane oxidation in the water column at other sites, too."

See also:

http://www.reportingclimatescience.com/news-stories/article/currents-trigger-methane-release-from-arctic.html
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AbruptSLR

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Re: Arctic Methane Release
« Reply #223 on: April 29, 2015, 10:17:21 PM »
The linked reference indicates that due to the unique chemical signature of the ancient permafrost dissolved organic carbon (DOC), that these DOC's can be rapidly utilized by microbes (~ 50% DOC loss in less than 7 days):

Spencer, R. G. M., P. J. Mann, T. Dittmar, T. I. Eglinton, C. McIntyre, R. M. Holmes, N. Zimov, and A. Stubbins (2015), "Detecting the signature of permafrost thaw in Arctic rivers", Geophysical Research Letters, 42, doi: 10.1002/2015GL063498

http://onlinelibrary.wiley.com/wol1/doi/10.1002/2015GL063498/abstract

Abstract: "Climate change induced permafrost thaw in the Arctic is mobilizing ancient dissolved organic carbon (DOC) into headwater streams; however, DOC exported from the mouth of major arctic rivers appears predominantly modern. Here we highlight that ancient (>20,000 years B.P.) permafrost DOC is rapidly utilized by microbes (~50% DOC loss in <7 days) and that permafrost DOC decay rates (0.12 to 0.19 day−1) exceed those for DOC in a major arctic river (Kolyma: 0.09 day−1). Permafrost DOC exhibited unique molecular signatures, including high levels of aliphatics that were rapidly utilized by microbes. As microbes processed permafrost DOC, its distinctive chemical signatures were degraded and converged toward those of DOC in the Kolyma River. The extreme biolability of permafrost DOC and the rapid loss of its distinct molecular signature may explain the apparent contradiction between observed permafrost DOC release to headwaters and the lack of a permafrost signal in DOC exported via major arctic rivers to the ocean."
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AbruptSLR

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Re: Arctic Methane Release
« Reply #224 on: April 30, 2015, 03:39:11 AM »
The linked (open access) reference discusses advanced model results for estimating methane emissions from Arctic lakes, citing emission rates of up to 538 mg CH4 m−2 d−1

Zeli Tan, Qianlai Zhuang & Katey Walter Anthony (2015), "Modeling methane emissions from arctic lakes: Model development and site-level study", JAMES, DOI: 10.1002/2014MS000344View

http://onlinelibrary.wiley.com/doi/10.1002/2014MS000344/full

Abstract: "To date, methane emissions from lakes in the pan-arctic region are poorly quantified. In order to investigate the response of methane emissions from this region to global warming, a process-based climate-sensitive lake biogeochemical model was developed. The processes of methane production, oxidation, and transport were modeled within a one-dimensional sediment and water column. The sizes of 14C-enriched and 14C-depleted carbon pools were explicitly parameterized. The model was validated using observational data from five lakes located in Siberia and Alaska, representing a large variety of environmental conditions in the arctic. The model simulations agreed well with the measured water temperature and dissolved CH4 concentration (mean error less than 1°C and 0.2 μM, respectively). The modeled CH4 fluxes were consistent with observations in these lakes. We found that bubbling-rate-controlling nitrogen (N2) stripping was the most important factor in determining CH4 fraction in bubbles. Lake depth and ice cover thickness in shallow waters were also controlling factors. This study demonstrated that the thawing of Pleistocene-aged organic-rich yedoma can fuel sediment methanogenesis by supplying a large quantity of labile organic carbon. Observations and modeling results both confirmed that methane emission rate at thermokarst margins of yedoma lakes was much larger (up to 538 mg CH4 m−2 d−1) than that at nonthermokarst zones in the same lakes and a nonyedoma, nonthermokarst lake (less than 42 mg CH4 m−2 d−1). The seasonal variability of methane emissions can be explained primarily by energy input and organic carbon availability."
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GeoffBeacon

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Re: Arctic Methane Release
« Reply #225 on: May 09, 2015, 08:48:27 PM »
Anyone seen this in the Siberian Times

Quote
Expert says deadly gas released from melting permafrost region will lead to 'awful' consequences for global warming.

http://siberiantimes.com/ecology/opinion/features/f0099-new-warning-about-climate-change-linked-to-peat-bogs/

Quote
A leading Siberian scientist has delivered another stark warning about climate change and said melting peat bogs could speed up the process.

Professor Sergey Kirpotin, director of the BioClimLand Centre of Excellence for Climate Change Research in Tomsk, said he has concerns over the 'awful' consequences in Russia’s sub-Arctic region.

He said that a thaw of the frozen bogs, which take up as much as 80 per cent of the landmass of western Siberia, will release billions of tonnes of methane – a greenhouse gas more potent than carbon dioxide – into the atmosphere. That, he concluded, will greatly speed up the effects of global warming around the world with potentially devastating consequences.

And Professor Sergey Kirpotin has such a nice smile.
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bill shockley

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Re: Arctic Methane Release
« Reply #226 on: May 21, 2015, 02:49:36 PM »
I hope I've chosen an appropriate forum to ask this question.

I first saw this image posted on Sam Carana's arctic-news blog:

https://robertscribbler.files.wordpress.com/2015/03/methane-jan21-31.jpg

It represents the same 10-day period in January from each of the years 2009-2013.

RobertScribbler described it in this post:

https://robertscribbler.wordpress.com/2015/03/09/cause-for-appropriate-concern-over-arctic-methane-overburden-plumes-eruptions-and-large-ocean-craters/

Quote
In the above image we see methane measurements at the 18,000 foot altitude above the Arctic and upper latitudes. The progression is from January of 2009 (furthest left) to January of 2013 (furthest right). Orange coloration represents methane readings in the range of 1850 to 1950 parts per billion. Deep red coloration is in the range of 2000 parts per billion. Note the shift from blues and yellows (1700-1800 ppb) to oranges and reds (1850-2000 ppb) during the five years from 2009 to 2013.

It's about the clearest, most compact argument I've seen for steady growth in methane emissions from the Arctic Ocean.

Are people reading too much into this? Is there any other top-down data that provides better evidence of growth?

Thanks for any help.

Also, I couldn't find any guidance on how to get images to embed. Any help would be appreciated.

oren

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Re: Arctic Methane Release
« Reply #227 on: May 24, 2015, 11:50:05 AM »
Anyone seen this in the Siberian Times

Quote
Expert says deadly gas released from melting permafrost region will lead to 'awful' consequences for global warming.

http://siberiantimes.com/ecology/opinion/features/f0099-new-warning-about-climate-change-linked-to-peat-bogs/

Quote
A leading Siberian scientist has delivered another stark warning about climate change and said melting peat bogs could speed up the process.

Professor Sergey Kirpotin, director of the BioClimLand Centre of Excellence for Climate Change Research in Tomsk, said he has concerns over the 'awful' consequences in Russia’s sub-Arctic region.

He said that a thaw of the frozen bogs, which take up as much as 80 per cent of the landmass of western Siberia, will release billions of tonnes of methane – a greenhouse gas more potent than carbon dioxide – into the atmosphere. That, he concluded, will greatly speed up the effects of global warming around the world with potentially devastating consequences.

And Professor Sergey Kirpotin has such a nice smile.

I've read it already. This is the Joker in terms of runaway positive feedback.

anotheramethyst

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Re: Arctic Methane Release
« Reply #228 on: June 18, 2015, 09:55:31 AM »
couldn't find a "arctic sea ice graphs page" topic so i put this video under its actual intended topic intead.



paul beckwith on recent arctic methane readings.... but that's not the cool part.  it's REALLY a video of paul beckwith using, among other resources, neven's arctic sea ice graphs page.  i thought that was pretty cool.

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Re: Arctic Methane Release
« Reply #229 on: June 18, 2015, 02:48:14 PM »
He used to comment on here. In fact, I wondered if it was him voting zero in the polls.

anotheramethyst

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Re: Arctic Methane Release
« Reply #230 on: June 18, 2015, 09:08:04 PM »
hahaha!!!!! that sounds like a reasonable guess :) now im gonna wonder if any other climate "celebrities" r on here.... richard alley would be cool.

AbruptSLR

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Re: Arctic Methane Release
« Reply #231 on: July 16, 2015, 11:37:14 PM »
The attached image shows satellite measured methane atmospheric concentrations at 469mb on July 14, 2015, & indicates readings as high as 2229PPB in the Arctic regions:
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Nick_Naylor

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Re: Arctic Methane Release
« Reply #232 on: August 20, 2015, 01:29:46 AM »
Not quite sure what to make of this paper:
http://phys.org/news/2015-08-warmer-earth-arctic-methane.html

The headline on phys.org is "On warmer Earth, most of Arctic may remove, not add, methane"

You can imagine what WUWT is making of this, and Andy Revkin has tweeted as though this changes everything. I have been unable to find any serious reaction to it.

solartim27

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Re: Arctic Methane Release
« Reply #233 on: August 20, 2015, 05:37:16 AM »
Yeah, we'll all have developed gills by then.
Quote
During a three-year period, a carbon-poor site on Axel Heiberg Island in Canada's Arctic region consistently took up more methane as the ground temperature rose from 0 to 18 degrees Celsius (32 to 64.4 degrees Fahrenheit). The researchers project that should Arctic temperatures rise by 5 to 15 degrees Celsius over the next 100 years, the methane-absorbing capacity of "carbon-poor" soil could increase by five to 30 times.

Read more at: http://phys.org/news/2015-08-warmer-earth-arctic-methane.html#jCp
FNORD

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Re: Arctic Methane Release
« Reply #234 on: September 02, 2015, 01:15:54 PM »
Has anyone seen this paper, which suggests that the Arctic may actually become a net methane sink as it warms? Basically certain Arctic soils that are currently absorbing methane appear likely to become better sinks as the Arctic warms - especially if they are subject to dry conditions in the summertime.

Deniers are seizing it as though it overturns everything that came before it (big surprise), but it might actually be important even if the effect is smaller than that:

http://www.princeton.edu/geosciences/news/geochemistry/LauEtAl_2015_ISMEJ_methane_sink.pdf
http://www.princeton.edu/geosciences/news/archive/?id=14884

http://wattsupwiththat.com/2015/08/19/the-arctic-methane-emergency-appears-canceled-due-to-methane-eating-bacteria/
https://arizonadailyindependent.com/2015/08/21/arctic-methane-scare-cancelled/

Edit: I suspect that sharing to link of the actual full text of the paper might cause it to disappear. Every other link I found was paywalled.

AbruptSLR

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Re: Arctic Methane Release
« Reply #235 on: September 19, 2015, 01:15:46 AM »
The linked open access reference shows that methane emissions from the tundra increase as Artic Sea Ice, ASI, extent decreases.  Thus we can expect a surge in methane emissions from the tundra if/when the ASI extent collapses.

Frans-Jan W. Parmentier, Wenxin Zhang, Yanjiao Mi, Xudong Zhu, Jacobus van Huissteden, Daniel J. Hayes, Qianlai Zhuang, Torben R. Christensen and A. David McGuire (2015), Rising methane emissions from northern wetlands associated with sea ice decline", Geophysical Research Letters, DOI: 10.1002/2015GL065013

http://onlinelibrary.wiley.com/doi/10.1002/2015GL065013/abstract

Abstract: "The Arctic is rapidly transitioning toward a seasonal sea ice-free state, perhaps one of the most apparent examples of climate change in the world. This dramatic change has numerous consequences, including a large increase in air temperatures, which in turn may affect terrestrial methane emissions. Nonetheless, terrestrial and marine environments are seldom jointly analyzed. By comparing satellite observations of Arctic sea ice concentrations to methane emissions simulated by three process-based biogeochemical models, this study shows that rising wetland methane emissions are associated with sea ice retreat. Our analyses indicate that simulated high-latitude emissions for 2005–2010 were, on average, 1.7 Tg CH4 yr−1 higher compared to 1981–1990 due to a sea ice-induced, autumn-focused, warming. Since these results suggest a continued rise in methane emissions with future sea ice decline, observation programs need to include measurements during the autumn to further investigate the impact of this spatial connection on terrestrial methane emissions."


See also:
http://www.lunduniversity.lu.se/article/melting-arctic-sea-ice-accelerates-methane-emissions
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AbruptSLR

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Re: Arctic Methane Release
« Reply #236 on: October 14, 2015, 07:11:06 PM »
Woods Hole is an eminently qualified research center, and when they issue a policy brief (see linked pdf) stating that GHG emissions from permafrost could lead to out-of-control global warming within decades, such advice should not be ignored:

http://whrc.org/wp-content/uploads/2015/06/PB_Permafrost.pdf

Extract: "Carbon emissions from thawing arctic permafrost will become substantial within decades, likely exceeding current emissions from fossil fuel combustion in the United States. This will greatly complicate efforts to keep global warming below 2°C and adds urgency to limiting anthropogenic emissions. Unlike fossil fuel emissions, emissions from thawing permafrost build on themselves, because the warming they cause leads to even greater emissions. For this reason, emissions from permafrost could lead to out-of-control global warming."
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johnm33

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Re: Arctic Methane Release
« Reply #237 on: November 18, 2015, 12:18:10 PM »
These look ready to pop
"Large mounds - described as pingos - have been identified on the seabed off the Yamal Peninsula, and their formation is seen as due to the thawing of subsea permafrost, causing a 'high accumulation' of methane gas."
http://siberiantimes.com/science/casestudy/features/f0183-leaking-pingos-can-explode-under-the-sea-in-the-arctic-as-well-as-on-land/

AbruptSLR

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Re: Arctic Methane Release
« Reply #238 on: November 20, 2015, 08:10:23 PM »
While the linked (open access) reference does not talk methane, it does talk about pingo formation, and as pingos can vent methane (see Reply #237), I am posting in this thread:

Samsonov, S. V., Lantz, T. C., Kokelj, S. V., and Zhang, Y.: Growth of a young pingo in the Canadian Arctic observed by RADARSAT-2 interferometric satellite radar, The Cryosphere Discuss., 9, 6395-6421, doi:10.5194/tcd-9-6395-2015, 2015.

http://www.the-cryosphere-discuss.net/9/6395/2015/tcd-9-6395-2015.pdf

Abstract. Advancements in radar technology are increasing our ability to detect earth surface deformation in permafrost environments. In this paper we use satellite Differential Interferometric Synthetic Aperture Radar (DInSAR) to describe the growth of a previously unreported pingo in the Tuktoyaktuk Coastlands. High-resolution RADARSAT-2 imagery (2011–2014) analyzed with the Multidimensional Small Baseline Subset (MSBAS) DInSAR revealed a maximum 2.7 cm yr−1 of domed uplift located in a drained lake basin. Observed changes in elevation were modeled as a 348 m × 290 m uniformly loaded elliptical plate with clamped edge. Model results suggest that this feature is one of the largest diameter pingos in the region that is presently growing. Analysis of historical aerial photographs showed that ground uplift at this location initiated sometime between 1935 and 1951 following lake drainage. Uplift is largely due to the growth of intrusive ice, because the 9 % expansion of pore water associated with permafrost aggradation into saturated sands is not sufficient to explain the observed short- and long-term deformation rates. The modeled thickness of permafrost using the Northern Ecosystem Soil Temperature (NEST) was consistent with the maximum height of this feature and the 1972–2014 elevation changes estimated from aerial photographs, suggesting that permafrost aggradation is resulting in the freezing a sub-pingo water lens. Seasonal variation in the uplift rate seen in the DInSAR data also matches the modeled seasonal pattern in the deepening rate of freezing front. This study demonstrates that interferometric satellite radar can successfully contribute to understanding the dynamics of terrain uplift in response to permafrost aggradation and ground ice development in remote polar environments, and highlights possible application of detecting deformation of Martian landscapes. However, our DInSAR data did not show clear growth at other smaller pingos in contrast with field studies performed mainly before the 1990s. Further investigation of this apparent discrepancy may help define limitations of our processing methodology and DInSAR data.
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Lennart van der Linde

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Re: Arctic Methane Release
« Reply #239 on: November 30, 2015, 05:02:18 PM »
"Global warming will progress faster than what was previously believed. The reason is that greenhouse gas emissions that arise naturally are also affected by increased temperatures. This has been confirmed in a new study from Linköping University that measures natural methane emissions":
http://www.liu.se/forskning/forskningsnyheter/1.661226?l=en

"Over the past two years the research team at Linköping University has contributed to numerous studies that all point in the same direction: natural greenhouse gas emissions will increase when the climate gets warmer. In the latest study the researchers examined the emissions of the greenhouse gas methane from three lakes. The effects were clear and the methane emissions increased exponentially with temperature. Their measurements show that a temperature increase from 15 to 20 degrees Celsius almost doubled the methane level. The findings was recently published in Limnology and Oceanography."

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Re: Arctic Methane Release
« Reply #240 on: December 23, 2015, 11:17:45 AM »
I try to avoid reading about methane emissions if I can (head in the sand  :'( ), so not sure if this recent article has been posted already:
http://phys.org/news/2015-12-methane-emissions-arctic-cold-season.html
"The amount of methane gas escaping from the ground during the long cold period in the Arctic each year and entering Earth's atmosphere is likely much higher than estimated by current climate change models, concludes a major new study led by San Diego State University."


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Re: Arctic Methane Release
« Reply #241 on: December 23, 2015, 02:53:03 PM »
Thanks Clare, I haven't seen that study.
The supplementary:
http://www.pnas.org/content/suppl/2015/12/17/1516017113.DCSupplemental/pnas.201516017SI.pdf
The graphs/readings from those different towers attached.

Pmt111500

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Re: Arctic Methane Release
« Reply #242 on: January 06, 2016, 04:27:51 AM »
oops, I think it's time for me to look for a new place to add to favorites... http://methanetracker.org/ looks like being a finished project. (cats and plumbing warning)

Though f.e. http://euanmearns.com/the-methane-time-bomb/ shows the seasonal cycle of methane concentrations has the high point in winter time, this is due to the lack or significant slowdown of the normal breakdown mechanism in the atmosphere during the winter. The highest inputs of methane to atmosphere occur in autumn and spring as seen on many years in the lowest graph in the article. When the amount of light increases in spring the volumes quickly drop. This makes me guess the autumn methane releases would be the most critical in the development of yearly increase in its concentrations.
« Last Edit: January 06, 2016, 04:38:53 AM by Pmt111500 »
Amateur observations of Sea Ice since 2003.

Sigmetnow

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Re: Arctic Methane Release
« Reply #243 on: February 13, 2016, 04:42:19 PM »
New study published in the Journal of Geophysical Research – Biogeosciences, a publication of the American Geophysical Union, provides a comprehensive analysis of carbon flux on the tundra during the winter months.
Quote
Arctic tundra stores carbon during the summer and releases some of it during the winter. But a new study shows that carbon released during the winter now outweighs the summertime gains, resulting in a net loss of carbon to the atmosphere.

According to the study’s authors, these results suggest the northern tundra may be shifting from its historical role as a carbon sink to a carbon source. To date, the Arctic has warmed more than any other region globally and researchers expect this warming to continue in the coming decades. If the tundra becomes a carbon source, it could amplify global warming and accelerate climate change, according to the authors.
http://blogs.agu.org/geospace/2016/02/11/new-study-suggests-northern-tundra-shifting-from-carbon-sink-to-carbon-source/
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Apocalypse4Real

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New IASI Methane Spike Feb 20 2016
« Reply #244 on: February 22, 2016, 03:09:50 PM »
METOP 1-B IASI smashed through the last spike to hit 3096 PPB on Feb 20 2016 am.
http://megiddo666.apocalypse4real-globalmethanetracking.com/

My site has the images - not time to add here.

AbruptSLR

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Re: Arctic Methane Release
« Reply #245 on: April 01, 2016, 06:42:05 PM »
The linked (open access) reference downplays the importance of the ESAS as a source for recent atmospheric methane concentration events in the Arctic:

Berchet, A., Bousquet, P., Pison, I., Locatelli, R., Chevallier, F., Paris, J.-D., Dlugokencky, E. J., Laurila, T., Hatakka, J., Viisanen, Y., Worthy, D. E. J., Nisbet, E., Fisher, R., France, J., Lowry, D., Ivakhov, V., and Hermansen, O.: Atmospheric constraints on the methane emissions from the East Siberian Shelf, Atmos. Chem. Phys., 16, 4147-4157, doi:10.5194/acp-16-4147-2016, 2016

http://www.atmos-chem-phys.net/16/4147/2016/

Abstract. Subsea permafrost and hydrates in the East Siberian Arctic Shelf (ESAS) constitute a substantial carbon pool, and a potentially large source of methane to the atmosphere. Previous studies based on interpolated oceanographic campaigns estimated atmospheric emissions from this area at 8–17 TgCH4 yr−1. Here, we propose insights based on atmospheric observations to evaluate these estimates. The comparison of high-resolution simulations of atmospheric methane mole fractions to continuous methane observations during the whole year 2012 confirms the high variability and heterogeneity of the methane releases from ESAS. A reference scenario with ESAS emissions of 8 TgCH4 yr−1, in the lower part of previously estimated emissions, is found to largely overestimate atmospheric observations in winter, likely related to overestimated methane leakage through sea ice. In contrast, in summer, simulations are more consistent with observations. Based on a comprehensive statistical analysis of the observations and of the simulations, annual methane emissions from ESAS are estimated to range from 0.0 to 4.5 TgCH4 yr−1. Isotopic observations suggest a biogenic origin (either terrestrial or marine) of the methane in air masses originating from ESAS during late summer 2008 and 2009.
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salbers

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Re: Arctic Methane Release
« Reply #246 on: April 23, 2016, 06:27:12 PM »
The question then is how this can be reconciled with the higher (though uncertain) estimates (e.g. by Shakhova et. al. in 2014,2015).

Ebullition and storm-induced methane release from the East Siberian Arctic Shelf.

http://www.nature.com/ngeo/journal/v7/n1/full/ngeo2007.html

The East Siberian Arctic Shelf: towards further assessment of permafrost-related methane fluxes and role of sea ice.

http://rsta.royalsocietypublishing.org/content/373/2052/20140451
« Last Edit: April 23, 2016, 06:38:21 PM by salbers »

AbruptSLR

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Re: Arctic Methane Release
« Reply #247 on: April 23, 2016, 06:39:29 PM »
The question then is how this can be reconciled with the higher estimates (e.g. by Shakhova et. al. in 2015).

The East Siberian Arctic Shelf: towards further assessment of permafrost-related methane fluxes and role of sea ice.

http://rsta.royalsocietypublishing.org/content/373/2052/20140451

The paper that I cited considers the case through 2012, while your reference cites more recent observations.  Methane emissions from ESAS likely will follow a non-linear (exponential) curve with warming of the Arctic Ocean bottom water temperatures; thus how much emissions you expect depends on the timeframe considered and the forcing pathway that we are all going to follow.
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salbers

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Re: Arctic Methane Release
« Reply #248 on: April 23, 2016, 07:20:53 PM »
Good point about the timing of the papers. The paper you cited does have some good suggestions in the conclusions, such as improving the observation network.

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Re: Arctic Methane Release
« Reply #249 on: August 10, 2016, 02:26:26 PM »
From GRL:

No significant increase in long-term CH4 emissions on North Slope of Alaska despite significant increase in air temperature

Quote
Twenty-nine years of measurements show little change in seasonal mean land sector CH4 enhancements, despite an increase in annual mean temperatures of 1.2 ± 0.8°C/decade (2σ). The record does reveal small increases in CH4 enhancements in November and December after 2010 due to increased late-season emissions. The lack of significant long-term trends suggests that more complex biogeochemical processes are counteracting the observed short-term (monthly) temperature sensitivity of 5.0 ± 3.6 ppb CH4/°C. Our results suggest that even the observed short-term temperature sensitivity from the Arctic will have little impact on the global atmospheric CH4 budget in the long term if future trajectories evolve with the same temperature sensitivity.

As I understand it, at short time scales (monthly) increases in air temperature cause increases in CH4 emissions from the tundra, at least in August & September.  But over the long term, the ecosystem seems to be adjusting to the temperature rise (12C/century at Barrow), resulting in no increase in CH4 emissions despite a large increase in temperature.