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neal

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Re: Carbon emissions, totals, trends, etc
« Reply #50 on: March 28, 2015, 12:57:35 AM »
While there may be attempts in the US to minimize the release of methane with fracked wells, the exponential increase in the number of wells in the US and abroad mean that the amount of methane released in the fracking revolution is at least increasing at the same exponential rate as the number of wells.  The other intensifying factor is that many places in the world have no such voluntary emissions limit and the cost of the effort only reduces profit on an already slim profit margin.

Hastening the day when the big burps begin.

anthropocene

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Re: Carbon emissions, totals, trends, etc
« Reply #51 on: March 29, 2015, 12:33:21 PM »
Hi ASLR,

 Is there a typo in your post? You say that MIT measured c02e is 485ppm.  Then you say particulates are -55 c02e which if completely removed from the atmosphere would take us from 430 c02e to 475 c02e. Shouldn't this be 485 c02e to 540 ppm c02e?

JimD

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Re: Carbon emissions, totals, trends, etc
« Reply #52 on: March 29, 2015, 09:25:50 PM »
Hi ASLR,

 Is there a typo in your post? You say that MIT measured c02e is 485ppm.  Then you say particulates are -55 c02e which if completely removed from the atmosphere would take us from 430 c02e to 475 c02e. Shouldn't this be 485 c02e to 540 ppm c02e?

No ASLR is correct, but he is not assuming that the entire effect of the particulates would go away (which is correct also).

We 'currently' have co2e of approx 485 and the 'effective' co2e is approx 430.  This is due to the negative 55 co2e from the particulates.  If we instantly removed the entire anthro particulate emissions the new value for 'effective' co2e would be that 485 number.

But it is not really possible to remove it all so he is assuming that by 2020 we  will have reduced it significantly and (I am assuming here) that he also figured in the expected rise in co2 concentrations to estimate that by 2020 we will be at an 'effective' co2e of 475.  A pretty damn scary number all by itself as that is a 10% effective increase in 5 years - yikes! as they say.

Now the question is...did my explanation make your confusion worse or better :)
We do not err because truth is difficult to see. It is visible at a glance. We err because this is more comfortable. Alexander Solzhenitsyn

How is it conceivable that all our technological progress - our very civilization - is like the axe in the hand of the pathological criminal? Albert Einstein

anthropocene

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Re: Carbon emissions, totals, trends, etc
« Reply #53 on: March 30, 2015, 12:46:31 AM »
Thanks for that. No more confusion - makes perfect sense and is pretty obvious really - if I'd bothered to put my brain in gear before typing  :-[

AbruptSLR

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Re: Carbon emissions, totals, trends, etc
« Reply #54 on: March 30, 2015, 01:01:40 AM »
Thanks for that. No more confusion - makes perfect sense and is pretty obvious really - if I'd bothered to put my brain in gear before typing  :-[

For what it is worth, I belatedly concur with JimD's thoughtful explanation.
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neal

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Re: Carbon emissions, totals, trends, etc
« Reply #55 on: March 31, 2015, 02:59:25 AM »
Jai references wells leaking as much as 3000 m^3/yr.

Gazprom has about 160,000 to 170,000 km of pipeline that leak on average of 6,438 m^3/yr per km.

Per http://www.iea.org/publications/freepublications/publication/russiangas2006.pdf

jai mitchell

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Re: Carbon emissions, totals, trends, etc
« Reply #56 on: March 31, 2015, 06:20:46 PM »
neal

your referenced document says,

To date there are no verifiable estimates of the level of gas losses during normal
operations.

The issue I was raising is that these capped well failures and methane leakages are a legacy issue after we get to zero emissions.  Every oil and gas well will have to be continually visited and sealed to prevent a long-term runaway warming situation.
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AbruptSLR

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Re: Carbon emissions, totals, trends, etc
« Reply #57 on: April 07, 2015, 07:06:21 PM »
The linked SkepticalScience article provides a general overview of the modern GHG history before 2011; however, here I only repost the attached image and associate extract, that shows that most of the year to year variations in atmospheric GHG concentrations depends on variations in the land fraction patterns of absorption and  emissions, which is a complex function of various Earth systems.

https://www.skepticalscience.com/EmmissionsAcceleration.html

Extract: "As you can see, the fraction of CO2 that remains in the atmosphere (light blue) varies a lot from year to year and  depends mainly on the land fraction (green), which in turn depends in part on weather patterns that influence plant growth. The partitioning is not just a function of this year’s emissions, but a complex function that relates to the different rates of several independent processes active on land and in the ocean that run at different speeds."
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bosbas

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Re: Carbon emissions, totals, trends, etc
« Reply #58 on: April 13, 2015, 04:08:27 AM »
http://www.esrl.noaa.gov/gmd/ccgg/trends/global.html
Feb 2015 goes in the record books as the month the global mean CO2 surpassed 400 ppm.


AbruptSLR

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Re: Carbon emissions, totals, trends, etc
« Reply #59 on: April 22, 2015, 05:19:55 PM »
The linked National Geographic article (and associated image) shows that US primary energy related carbon emissions increased in 2014 even though the associated emissions from coal were declining:

http://news.nationalgeographic.com/energy/2015/04/150421-US-carbon-emissions-rise/
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AbruptSLR

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Re: Carbon emissions, totals, trends, etc
« Reply #60 on: January 25, 2016, 05:01:38 PM »
No one has posted in this thread for a while, so I thought that I would provide the attached plot from the linked website, indicating that as of Jan 11 2016, most GHG concentrations (at specific sites) in the atmosphere are increasing:

http://www.stateofourclimate.com/
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AbruptSLR

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Re: Carbon emissions, totals, trends, etc
« Reply #61 on: January 25, 2016, 05:33:39 PM »
The following website (& associated images for CH4 & N2O, respectively, for Sept 2015) offers another way to periodically track changes in GHG concentrations at selected locations:

http://agage.mit.edu/data/agage-data
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AbruptSLR

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Re: Carbon emissions, totals, trends, etc
« Reply #62 on: February 09, 2016, 11:29:03 PM »
So if world governments are making heroic efforts to reduce GHG emissions, why are the Mauna Loa CO2, CH4 and N2O concentrations so high through the first week in Feb 2016 (see respective plots)?
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AbruptSLR

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Re: Carbon emissions, totals, trends, etc
« Reply #63 on: March 01, 2016, 05:34:14 PM »
Since my last post on this topic the Mauna Loa CH4 concentration thru Feb 28 2016 have gone up into the 1880 ppb +/- range indicating both strong anthropogenic & natural methane emissions this year (following or exceeding the RCP 8.5 scenario for methane).  The first image shows the full record thru Feb 27 2016 and the second image shows a pike in methane concentration on Feb 28 2016.

Edit the third image show the Mauna Loa N2O concentration in 2016, which also shows a continuing increase.
« Last Edit: March 01, 2016, 05:39:32 PM by AbruptSLR »
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Laurent

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Re: Carbon emissions, totals, trends, etc
« Reply #64 on: March 10, 2016, 07:41:10 PM »
The hidden driver of climate change that we too often ignore
https://www.washingtonpost.com/news/energy-environment/wp/2016/03/09/the-hidden-driver-of-climate-change-that-we-too-often-ignore/

Humans are making global warming worse, all right — but in more ways than you think.

That’s the result of an important new study in Nature, which finds that the Earth’s land “biosphere” — defined as all the plants, animals and microorganisms living on the surface of the Earth (excluding the oceans) — is now a “net source” of greenhouse gases to the atmosphere. Thus, the biosphere is now adding to global warming in much the same way that all of our fossil fuels are.
Chris Mooney article

ALways it is said that the Nitous oxyde is around 300 times more ponent than CO2 over a  hundred years, but we should take the  10 years value if we want to be accurate with reality. Does some of you have this information ? A graph even better ?

AbruptSLR

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Re: Carbon emissions, totals, trends, etc
« Reply #65 on: March 14, 2016, 06:48:15 PM »
The linked reference indicates that the tropospheric hydroxyl distribution is more self-buffering than previously realized; while means that the GWP of CH4 is less likely to increase with increasing atmospheric concentrations:

Lelieveld, J., Gromov, S., Pozzer, A., and Taraborrelli, D.: Global tropospheric hydroxyl distribution, budget and reactivity, Atmos. Chem. Phys. Discuss., doi:10.5194/acp-2016-160, in review, 2016

http://www.atmos-chem-phys-discuss.net/acp-2016-160/

Abstract. The self-cleaning or oxidation capacity of the atmosphere is principally controlled by hydroxyl (OH) radicals in the troposphere. Hydroxyl has primary (P) and secondary (S) sources, the former through the photo-dissociation of ozone, the latter through OH recycling in radical reaction chains. We used the recent Mainz Organics Mechanism (MOM) to advance volatile organic carbon (VOC) chemistry in the general circulation model EMAC, and show that S is larger than previously assumed. MOM calculates substantially higher OH reactivity from VOC oxidation compared to predecessor models. Further, we find that nighttime OH formation may be significant in the polluted subtropical boundary layer in summer. Globally S exceeds P, most distinctively in the free troposphere. As a consequence, OH is buffered and not sensitive to perturbations by natural or anthropogenic emission changes. Complementary OH formation mechanisms in pristine and polluted environments of the continental and marine troposphere, connected through long-range transport of O3, maintain stable global OH levels.
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AbruptSLR

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Re: Carbon emissions, totals, trends, etc
« Reply #66 on: March 15, 2016, 06:25:21 PM »
The linked reference study (see images) the atmospheric methane evolution over the last 40 years and finds that natural processes continue to remove methane from the atmosphere resulting in a shorter methane life than previously feared.

Dalsøren, S. B., Myhre, C. L., Myhre, G., Gomez-Pelaez, A. J., Søvde, O. A., Isaksen, I. S. A., Weiss, R. F., and Harth, C. M.: Atmospheric methane evolution the last 40 years, Atmos. Chem. Phys., 16, 3099-3126, doi:10.5194/acp-16-3099-2016, 2016.

http://www.atmos-chem-phys.net/16/3099/2016/

Abstract. Observations at surface sites show an increase in global mean surface methane (CH4) of about 180 parts per billion (ppb) (above 10 %) over the period 1984–2012. Over this period there are large fluctuations in the annual growth rate. In this work, we investigate the atmospheric CH4 evolution over the period 1970–2012 with the Oslo CTM3 global chemical transport model (CTM) in a bottom-up approach. We thoroughly assess data from surface measurement sites in international networks and select a subset suited for comparisons with the output from the CTM. We compare model results and observations to understand causes for both long-term trends and short-term variations. Employing Oslo CTM3 we are able to reproduce the seasonal and year-to-year variations and shifts between years with consecutive growth and stagnation, both at global and regional scales. The overall CH4 trend over the period is reproduced, but for some periods the model fails to reproduce the strength of the growth. The model overestimates the observed growth after 2006 in all regions. This seems to be explained by an overly strong increase in anthropogenic emissions in Asia, having global impact. Our findings confirm other studies questioning the timing or strength of the emission changes in Asia in the EDGAR v4.2 emission inventory over recent decades. The evolution of CH4 is not only controlled by changes in sources, but also by changes in the chemical loss in the atmosphere and soil uptake. The atmospheric CH4 lifetime is an indicator of the CH4 loss. In our simulations, the atmospheric CH4 lifetime decreases by more than 8 % from 1970 to 2012, a significant reduction of the residence time of this important greenhouse gas. Changes in CO and NOx emissions, specific humidity, and ozone column drive most of this, and we provide simple prognostic equations for the relations between those and the CH4 lifetime. The reduced lifetime results in substantial growth in the chemical CH4 loss (relative to its burden) and dampens the CH4 growth.
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AbruptSLR

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Re: Carbon emissions, totals, trends, etc
« Reply #67 on: March 19, 2016, 06:14:57 PM »
The linked article indicates that natural gas has just surpassed coal as the primary source of electricity generation in the USA (see image).  This trend very likely is contributing to the recent spike in atmospheric CH4 concentration:

http://www.climatecentral.org/news/natural-gas-to-surpass-coal-for-electricity-20154

Extract: "This year is expected to be the first in U.S. history that more electricity will be generated from natural gas than coal, a new analysis has found …"
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sidd

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Re: Carbon emissions, totals, trends, etc
« Reply #68 on: March 19, 2016, 11:39:24 PM »
and looks like non hydro renewables just passed hydro

AbruptSLR

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Re: Carbon emissions, totals, trends, etc
« Reply #69 on: March 20, 2016, 06:05:25 PM »
While the linked article focuses on the environmental impacts of over 200 planned new dams on the Amazon rainforest; I note here that the associated lakes will generate a near-term pulse of increased methane emissions as the submerged rainforest decays:

https://www.washingtonpost.com/news/energy-environment/wp/2016/03/18/why-dams-are-such-bad-news-for-the-amazon-rainforest/

Extract: "Why more than 200 planned new dams will be a disaster for the Amazon rainforest"
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AbruptSLR

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Re: Carbon emissions, totals, trends, etc
« Reply #70 on: March 25, 2016, 05:52:48 PM »
The linked article cites satellite data to indicate that U.S. methane emissions have surged more than 30% in the last decade.  It is almost certain that this increase is primarily due to increases in fracking and the associate increased use of nature gas in the U.S.  I remind readers that no matter what the article says methane has 105 times the GWP of carbon dioxide over a 20-year period.

http://www.independent.co.uk/news/world/americas/fracking-could-be-behind-startling-increase-in-methane-surge-in-us-experts-say-a6914346.html

Extract: "New Harvard University research, drawing on satellite measurements, concludes that US emissions of methane – a much more powerful warming gas than carbon dioxide – have “increased by more than 30 per cent over the past decade”."
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AbruptSLR

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Re: Carbon emissions, totals, trends, etc
« Reply #71 on: March 26, 2016, 06:12:52 PM »
As a follow-up to my last post, the linked article provides an example of just what a "wicked problem" climate change really is, by discussing how the US natural gas bridge to the future of sustainable energy is most likely actually accelerating global warming.  The article points out that previous EPA procedures underestimated: (a) the GWP of methane; (b) the leakage rates for methane; and (c) the negative impacts of methane of suppressing the rate of development of more sustainable alternate energy sources.  Unfortunately, new fossil fuel emissions of methane account for less than 50% of the recent surge in global methane emissions; while increases in Asian agricultural sources have accounted for more than 50% of the new emissions.  Furthermore, the recent new Hansen et al (2016) shows that fossil fuels are not the only cause of concern for increasing planetary energy imbalances, as abrupt ice sheet mass loss could almost double the effective ECS value (if the postulated abrupt ice mass losses occur).  I could go on about how even Hansen et al errs on the side of least drama; but policy makers will probably adopt a wait and see attitude anyway:


http://www.thenation.com/article/global-warming-terrifying-new-chemistry/


Extract: "… molecule for molecule, this unburned methane is much, much more efficient at trapping heat than carbon dioxide.
The EPA insisted this wasn’t happening, that methane was on the decline just like CO2. But it turns out, as some scientists have been insisting for years, the EPA was wrong. Really wrong. This error is the rough equivalent of the New York Stock Exchange announcing tomorrow that the Dow Jones isn’t really at 17,000: Its computer program has been making a mistake, and your index fund actually stands at 11,000.
These leaks are big enough to wipe out a large share of the gains from the Obama administration’s work on climate change—all those closed coal mines and fuel-efficient cars. In fact, it’s even possible that America’s contribution to global warming increased during the Obama years. The methane story is utterly at odds with what we’ve been telling ourselves, not to mention what we’ve been telling the rest of the planet. It undercuts the promises we made at the climate talks in Paris. It’s a disaster—and one that seems set to spread.
 The Obama administration, to its credit, seems to be waking up to the problem. Over the winter, the EPA began to revise its methane calculations, and in early March, the United States reached an agreement with Canada to begin the arduous task of stanching some of the leaks from all that new gas infrastructure. But none of this gets to the core problem, which is the rapid spread of fracking. Carbon dioxide is driving the great warming of the planet, but CO2 isn’t doing it alone. It’s time to take methane seriously.



 The EPA’s old chemistry and 100-year time frame assigned methane a heating value of 28 to 36 times that of carbon dioxide; a more accurate figure, says Howarth, is between 86 and 105 times the potency of CO2 over the next decade or two.
If you combine Howarth’s estimates of leakage rates and the new standard values for the heat-trapping potential of methane, then the picture of America’s total greenhouse-gas emissions over the last 15 years looks very different: Instead of peaking in 2007 and then trending downward, as the EPA has maintained, our combined emissions of methane and carbon dioxide have gone steadily and sharply up during the Obama years, Howarth says.



 If the Harvard data hold up and we keep on fracking, it will be nearly impossible for the United States to meet its promised goal of a 26 to 28 percent reduction in greenhouse gases from 2005 levels by 2025.



 One of the nastiest side effects of the fracking boom, in fact, is that the expansion of natural gas has undercut the market for renewables, keeping us from putting up windmills and solar panels at the necessary pace. Joe Romm, a climate analyst at the Center for American Progress, has been tracking the various economic studies more closely than anyone else. Even if you could cut the methane-leakage rates to zero, Romm says, fracked gas (which, remember, still produces 50 percent of the CO2 level emitted by coal when you burn it) would do little to cut the world’s greenhouse-gas emissions because it would displace so much truly clean power.



 The global-warming fight can’t just be about carbon dioxide any longer."
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Bruce Steele

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Re: Carbon emissions, totals, trends, etc
« Reply #72 on: April 22, 2016, 05:10:04 PM »
The trillionth ton carbon counter has now surpassed the 600Gt mark.

http://www.trillionthtonne.org/


AbruptSLR

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Re: Carbon emissions, totals, trends, etc
« Reply #73 on: May 01, 2016, 11:24:23 AM »
The linked NOAA ESRL Annual Greenhouse Gas Index (AGGI) website has now been updated in the Spring of 2016 with data through the end of 2015.  The linked data (& attached images) indicate that: (a) the 2015 radiative forcing was 2.974 watts/sq m; (b) AGGI (2015) was 1.374; and (c) CO₂-e was 485ppm.  These all indicate that in 2015 we continued on a BAU pathway:

http://www.esrl.noaa.gov/gmd/aggi/aggi.html


Edit: Note that the second image confirms that in 2015, CO2, CH4 and N2O atmospheric concentrations increased worldwide.
« Last Edit: May 01, 2016, 11:31:27 AM by AbruptSLR »
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Shared Humanity

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Re: Carbon emissions, totals, trends, etc
« Reply #74 on: May 01, 2016, 04:43:41 PM »
For the past 2 years CO2 emissions from energy consumption has stalled despite the the rapid run up in atmospheric CO2. Here's hoping that the dramatic increase in atmospheric CO2 is the effect of the strong El Nino and not evidence of feedbacks.

http://www.carbonbrief.org/10-charts-showing-why-carbon-emissions-stalled-last-year

ghoti

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Re: Carbon emissions, totals, trends, etc
« Reply #75 on: May 01, 2016, 07:10:13 PM »
We are only recently realizing the massive amount of fugitive ethane and methane being released but not accounted for by fracking in North America. Is it reasonable to expect a massive amount of CO2 is also leaking and not accounted for via the same leaks? These are after all huge carbon sources.

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Re: Carbon emissions, totals, trends, etc
« Reply #76 on: May 01, 2016, 10:55:16 PM »
ghoti -  Sadly not. The carbon is mostly long chain, even when it's been cooked and broken down in to methane and pentane, it's still a chained molecule. I say sadly, as methane has upto 100 times the co2 warming potential in it's first few years of release. This power decreases as it's broken down in the atmosphere by hydroxl and sunlight to become co2 which last for hundreds of years in the atmosphere.


AbruptSLR

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Re: Carbon emissions, totals, trends, etc
« Reply #77 on: May 03, 2016, 12:06:44 AM »
The linked reference (and related following linked article) indicates that what GHG GWP values that one should use to set policy depends on the timeframe that one is concerned about.  If one is concerned that the WAIS could be destabilized by 2030 (or that ECS is in the 4 to 5C range) one would focus on values that encourage limiting short-lived climate pollutants (SLCPs) like methane or black carbon; otherwise, one would use values that promote reductions in CO₂ emissions:

Myles R. Allen, Jan S. Fuglestvedt, Keith P. Shine, Andy Reisinger, Raymond T. Pierrehumbert & Piers M. Forster (2016), "New use of global warming potentials to compare cumulative and short-lived climate pollutants", Nature Climate Change, doi:10.1038/nclimate2998


http://www.nature.com/nclimate/journal/vaop/ncurrent/full/nclimate2998.html

Abstract: "Parties to the United Nations Framework Convention on Climate Change (UNFCCC) have requested guidance on common greenhouse gas metrics in accounting for Nationally determined contributions (NDCs) to emission reductions. Metric choice can affect the relative emphasis placed on reductions of ‘cumulative climate pollutants’ such as carbon dioxide versus ‘short-lived climate pollutants’ (SLCPs), including methane and black carbon. Here we show that the widely used 100-year global warming potential (GWP100) effectively measures the relative impact of both cumulative pollutants and SLCPs on realized warming 20–40 years after the time of emission. If the overall goal of climate policy is to limit peak warming, GWP100 therefore overstates the importance of current SLCP emissions unless stringent and immediate reductions of all climate pollutants result in temperatures nearing their peak soon after mid-century, which may be necessary to limit warming to “well below 2 °C”. The GWP100 can be used to approximately equate a one-off pulse emission of a cumulative pollutant and an indefinitely sustained change in the rate of emission of an SLCP. The climate implications of traditional CO2-equivalent targets are ambiguous unless contributions from cumulative pollutants and SLCPs are specified separately."


https://www.washingtonpost.com/news/energy-environment/wp/2016/05/02/why-were-still-so-incredibly-confused-about-methanes-role-in-global-warming/

Extract: "It’s perhaps the most contentious issue in U.S. climate change policy right now: How can we deal with emissions of methane, a powerful if short-lived greenhouse gas, which has many sources but appears to be leaking into the air in considerable volumes from U.S. oil and gas operations?"
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AbruptSLR

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Re: Carbon emissions, totals, trends, etc
« Reply #78 on: June 15, 2016, 06:54:56 PM »
The attached plot shows the Mauna Loa atmospheric CH4 concentrations thru June 11 2016, indicating the recent up-tick in methane concentrations (combined anthropogenic & natural) is continuing.
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AbruptSLR

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Re: Carbon emissions, totals, trends, etc
« Reply #79 on: July 03, 2016, 05:18:33 PM »
The linked article indicates that industry has been under-reporting methane gas leaks; and that new detection devices may soon verify that leakage rates are higher than previously assumed:

http://www.smh.com.au/environment/climate-change/sleeper-issue-of-leaking-coal-seam-gas-fields-may-blow-hole-in-emissions-goals-20160622-gpph1q.html
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abbottisgone

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Re: Carbon emissions, totals, trends, etc
« Reply #80 on: July 04, 2016, 04:39:08 AM »

I think that few policymakers understand the seriousness of the rapidly approaching climate consequences.

Indeed SLR, however it should also be noted that the 10-year time lag of full warming potential realization indicates that we are currently operating at a level only a few years after China began to triple the rate of its coal consumption. 

The only thing that has maintained reasonably steady temperatures has been the aerosols, the INCREASE of aerosols and the effect of these aerosols on local regional dimming and global impacts.  If my understanding is correct and surface flows are severely impacted in the western pacific, causing the unusual PDO effect over the last 10 years, then a LACK OF INCREASE of aerosols will likely cause this system to 'flip'.  producing a non-linear 'tipping point' response over the next 4 years.
Carbon emissions take 40 years to be felt...
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But I left school and grew my hair
They didn't understand
They wanted me to be respected as
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But I had other plans..........

abbottisgone

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Re: Carbon emissions, totals, trends, etc
« Reply #81 on: July 04, 2016, 04:42:01 AM »
The intelligent people who wanted a carbon tax wanted the money given to the people not wasting energy, which are the poor. My strategy is to make energy so cheap we get the monkey off our backs. We can convert to that method in about ten years and start retiring those dinosaur industries, including our nukes to a new generation of processes generating energy that doesn't pollute our atmosphere with CO2 or anything. We just have to be determined to do it.

We can start now or wait until the next shoe falls.

What about the good folks over in Denmark and Norway? How do you want to make your stand?
Denmark and Norway hardly represent normality!
..
But I left school and grew my hair
They didn't understand
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Apocalypse4Real

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Re: Carbon emissions, totals, trends, etc
« Reply #82 on: July 08, 2016, 10:36:26 PM »
Global CO2 was above 404 ppm for May 2016. The 5 year and 10 year comparison trends continue to accelerate despite the end of El Nino.

See: http://www.megiddo666.apocalypse4real-globalmethanetracking.com/2016/07/monthly-global-co2-spikes-above-404-ppm.html


AbruptSLR

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Re: Carbon emissions, totals, trends, etc
« Reply #83 on: July 08, 2016, 10:39:38 PM »
Global CO2 was above 404 ppm for May 2016. The 5 year and 10 year comparison trends continue to accelerate despite the end of El Nino.
A4R,

Great to see you posting here again.  Keep it up :)

ASLR
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AbruptSLR

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Re: Carbon emissions, totals, trends, etc
« Reply #84 on: July 24, 2016, 05:08:09 AM »
The attached plot from the linked website indicates that the Copernicus Atmospheric Monitoring system projects a lot of CO2 emissions from burning:

http://macc.copernicus-atmosphere.eu/d/services/gac/nrt/nrt_fields_ghg!Carbon%20dioxide!Total%20column!120!Global!macc!od!enfo!nrt_fields_ghg!2015101200!!/
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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AbruptSLR

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Re: Carbon emissions, totals, trends, etc
« Reply #85 on: July 24, 2016, 05:44:04 PM »
The linked article indicates that Russia's (& other countries') policy of letting wildfires burn, does not only increase CO₂ emissions, but also decreases CO₂ absorption:

http://www.japantimes.co.jp/news/2016/07/22/world/science-health-world/russian-wildfires-put-key-climate-change-resource-risk/#.V5ThBE1gleV

Extract: " Russia’s practice of leaving massive wildfires to burn out of control in sprawling stretches of Siberia puts at risk a key global resource for absorbing climate-warming emissions: its trees.
The blazes are consuming millions of hectares of pristine Boreal forests in Russia, which are second only to the world’s tropical jungles in capturing planet-warming carbon emissions.
At the same time, the drier and harsher conditions associated with a warmer climate — June was the hottest ever recorded — are contributing to the fires becoming ever bigger and more common.

Russia’s forestry agency chief Ivan Valentik said however that most wildfires that don’t threaten people will likely only be monitored not extinguished.
“Not a single country has any desire or capability to stop natural fires that don’t threaten towns or economic infrastructure … there is not a single reason to attend to them,” he said."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: Carbon emissions, totals, trends, etc
« Reply #86 on: August 10, 2016, 11:51:11 AM »
Per the linked reference we can reduce methane emissions from global rice production by the use of optimized water management practices.

Bowen Zhang, Hanqin Tian, Wei Ren, Bo Tao, Chaoqun Lu, Jia Yang, Kamaljit Banger & Shufen Pan (8 August 2016), "Methane Emissions from global rice fields: Magnitude, spatio-temporal patterns and environmental controls", Global Biogeochemical Cycles, DOI: 10.1002/2016GB005381

http://onlinelibrary.wiley.com/doi/10.1002/2016GB005381/abstract

Abstract: "Given the importance of the potential positive feedback between methane (CH4) emissions and climate change, it is critical to accurately estimate the magnitude and spatio-temporal patterns of CH4 emissions from global rice fields and better understand the underlying determinants governing the emissions. Here, we used a coupled biogeochemical model in combination with satellite-derived contemporary inundation area to quantify the magnitude and spatio-temporal variation of CH4 emissions from global rice fields and attribute the environmental controls of CH4 emissions during 1901-2010. Our study estimated that CH4 emissions from global rice fields varied from 18.3 ± 0.1 Tg CH4/yr (Avg. ± 1 std. dev.) under intermittent irrigation to 38.8 ± 1.0 Tg CH4/yr under continuous flooding in the 2000s, indicating that the magnitude of CH4 emissions from global rice fields was largely dependent on different water schemes. Over the past 110 years, our simulated results showed that global CH4 emissions from rice cultivation increased 85%. The expansion of rice fields was the dominant factor for the increasing trends of CH4 emissions, followed by elevated CO2 concentration, and nitrogen fertilizer use. On the contrary, climate had the negative effect on the cumulative CH4 emissions for most of the years over the study period. Our results imply that CH4 emissions from global rice fields could be reduced through implementing optimized irrigation practices. Therefore, the future magnitude of CH4 emissions from rice fields will be determined by the human demand for rice production as well as the implementation of optimized water management practices."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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AbruptSLR

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Re: Carbon emissions, totals, trends, etc
« Reply #87 on: August 23, 2016, 05:36:27 PM »
It seems to me that air-conditioning and refrigeration represent a bigger climate risk than most authorities are willing to admit publically.  I am posting in this thread so we do not lose sight of the HFC emissions:

https://www.theguardian.com/environment/2016/aug/22/why-air-conditioning-vicious-circle-weatherwatch

Extract: "With the demand for air conditioning rising worldwide, it’s reckoned that in around 30 years’ time more energy could be used for cooling than for heating.

Air conditioning also pumps out heat straight into the atmosphere. Like a fridge, it takes heat from the inside of a building or car, then transfers it to the warm outside. That extra heat makes cities hotter, raising night-time temperatures by up to 2C, which then encourages people to turn up their air conditioning even higher.

And there’s another sting to keeping cool. Air conditioning systems also use powerful greenhouse gases called hydrofluorocarbons (HFCs), thousands of times more potent than carbon dioxide. These gases leak out into the atmosphere, especially from vehicles, and global emissions of HFCs rose by more than half between 2007 and 2012, adding to the burden of climate change even more.
And as the climate grows hotter, there’s more need to stay cool. It’s a vicious circle."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

TerryM

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Re: Carbon emissions, totals, trends, etc
« Reply #88 on: August 23, 2016, 06:43:22 PM »
ASLR
Canada has been seeing peek electric loads during cooling season rather than heating season for some time. AC has gone from a rather ostentatious display of opulence to an expected convenience in private homes, offices & factories.


I'd assume that this would hold true for the States & Europe.


Slightly OT is the fact that few are aware of a heat pump's lack of efficiency at under 40F (4.5 C). It simply requires so much energy to defrost the condenser coil that  even strip (resistive) heat is less expensive. This applies to Air/Air, Water/Air, or Geo./Air units. The condenser side needs >4.5 C or the unit can't work efficiently.


Terry

Bruce Steele

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Re: Carbon emissions, totals, trends, etc
« Reply #89 on: August 23, 2016, 07:33:05 PM »
Terry, Hate to be dense but I would like to make sure I understand you correctly. If ,for example ,you would choose to run an air conditioner with the temperature outside at anything below 40 F  it won't work very well because the condensers will freeze up ?  Probably more applicable to a refrigerator in someone's garage as an example but do I understand your point about frozen condensation on a condenser ?

sesyf

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Re: Carbon emissions, totals, trends, etc
« Reply #90 on: August 23, 2016, 08:16:02 PM »
At least here in Finland the air to air heat pumps are considered to work up to -20 C for the best models; also it's said that they need to be kept running even when colder, to prevent outside unit from freezing - at least some models are 'thawed' at some point with sort of reversing the heatflow from inside the house to outside unit, if I have understood the workings correctly.

Last winter was not very cold hereabouts so cannot say if there would be real issues in even colder situations - at least the different versions, air to air, air to water etc have sold well here.

TerryM

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Re: Carbon emissions, totals, trends, etc
« Reply #91 on: August 24, 2016, 04:51:04 AM »
Bruce
Hope I steer away from the pedantic, but:
A heat pump can be thought of as an AC that sometimes runs in reverse. Since (almost) all units provide both heating and cooling the outside coil is referred to as the condenser coil, even though it actually acts as an evaporator during most of the heat cycle.
If ambient temperatures are well above freezing the unit requires very few defrost cycles to keep the air or water from insulating the coil with ice and restricting air or water flow.
To defrost, a reversing valve reverses the flow of refrigerant through the system and a diverter stops the flow of now chilled air entering the interior space, The cooler the outside air becomes, the more often defrosting is necessary & the longer it takes to melt away the ice. Strip heaters are sometimes incorporated into both the outer coil to aid defrost and in the ducting space for inside air so that heating is maintained even during defrost.
AC refrigeration and heating systems operate by cooling or heating air by 20F on each pass through the coil. At 40F air passing through the coil will be chilled to 20F until ice builds up and begins restricting the flow, then the temperature drops. Even with very dry air, moisture condenses and ice forms rapidly.
The warmer the ambient is, the more efficient a heat pump will be. At <~40F it requires so much energy, and time, to defrost that less electricity will be used by simply using resistance heaters.


sesyf
At -20C, -4F, an air/air heat pump won't be efficient. At least no system that I've seen or can imagine. If you consider that a heat pump operates by extracting heat from the outside air it becomes evident that continuous running in very cold weather will not prevent freezing, rather the opposite.
I don't doubt that heat pumps are being sold, even in locations where other systems would be preferable. Few people know how much energy their heating system draws, even fewer care, besides, with a heat pump a stand alone AC unit isn't required. Simple, cheap and easy to install.
Terry

ghoti

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Re: Carbon emissions, totals, trends, etc
« Reply #92 on: August 24, 2016, 06:19:36 AM »
There are now several brands of air source heat pumps that operate quite efficiently at -20C (COP of 2). I can't properly explain the magic used to maintain efficiency at those temperatures but there's more than one method used to accomplish it.

But always efficient and never needing defrosting ground source heat pumps maintain huge efficiency (COP up to 4) for both heating and cooling. There are at least two ways to achieve efficient heat exchange for the ground source - fluid mediated and direct exchange.

Heat pumps are definitely going to be important in our fossil fuel free future.

Bruce Steele

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Re: Carbon emissions, totals, trends, etc
« Reply #93 on: August 26, 2016, 12:19:56 PM »
A4R has a nice graph showing Increases of global CO2 for the one , five , and ten year trend lines that also shows rate increases for all three.

http://www.megiddo666.apocalypse4real-globalmethanetracking.com/

AbruptSLR

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Re: Carbon emissions, totals, trends, etc
« Reply #94 on: September 15, 2016, 01:34:04 AM »
The linked PNAS reference indicates that particularly in the past decade anthropogenic methane emissions have been increasing much faster than previously reported:

Andrew L. Rice, Christopher L. Butenhoff, Doaa G. Teama, Florian H. Röger, M. Aslam K. Khalil and Reinhold A. Rasmussen (2016), "Atmospheric methane isotopic record favors fossil sources flat in 1980s and 1990s with recent increase", PNAS, doi: 10.1073/pnas.1522923113

http://www.pnas.org/content/early/2016/09/06/1522923113

Abstract: "Observations of atmospheric methane (CH4) since the late 1970s and measurements of CH4 trapped in ice and snow reveal a meteoric rise in concentration during much of the twentieth century. Since 1750, levels of atmospheric CH4 have more than doubled to current globally averaged concentration near 1,800 ppb. During the late 1980s and 1990s, the CH4 growth rate slowed substantially and was near or at zero between 1999 and 2006. There is no scientific consensus on the drivers of this slowdown. Here, we report measurements of the stable isotopic composition of atmospheric CH4 (13C/12C and D/H) from a rare air archive dating from 1977 to 1998. Together with more modern records of isotopic atmospheric CH4, we performed a time-dependent retrieval of methane fluxes spanning 25 y (1984–2009) using a 3D chemical transport model. This inversion results in a 24 [18, 27] Tg y−1 CH4 increase in fugitive fossil fuel emissions since 1984 with most of this growth occurring after year 2000. This result is consistent with some bottom-up emissions inventories but not with recent estimates based on atmospheric ethane. In fact, when forced with decreasing emissions from fossil fuel sources our inversion estimates unreasonably high emissions in other sources. Further, the inversion estimates a decrease in biomass-burning emissions that could explain falling ethane abundance. A range of sensitivity tests suggests that these results are robust."

Also see:
https://www.washingtonpost.com/news/energy-environment/wp/2016/09/13/the-answer-to-the-global-methane-mystery-fossil-fuels-a-study-finds/?utm_term=.9c3d5b61cc09

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AbruptSLR

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Re: Carbon emissions, totals, trends, etc
« Reply #95 on: October 06, 2016, 01:30:38 AM »
The linked reference indicates that methane emissions are much higher than previously estimated; which explains why atmospheric methane concentrations are increasing, and which will also make it less likely that the IPCC will achieve their stated goals:

Stefan Schwietzke, Owen A. Sherwood, Lori M. P. Bruhwiler, John B. Miller, Giuseppe Etiope, Edward J. Dlugokencky, Sylvia Englund Michel, Victoria A. Arling, Bruce H. Vaughn, James W. C. White & Pieter P. Tans (06 October 2016), "Upward revision of global fossil fuel methane emissions based on isotope database", Nature, doi:10.1038/nature19797

http://www.nature.com/nature/journal/v538/n7623/full/nature19797.html

&

http://www.nature.com/articles/nature19797.epdf?referrer_access_token=p6_LpMh9PB1AysWGs92qndRgN0jAjWel9jnR3ZoTv0M65pTu-meS4gM65_CHaFER1lif4oa9unP0ZqkRx7GIqTpiG2x4kaayiiBco7CLfuv-lt2m-2AfMBjykyw-PSMRhqwIgVKyU_xWo0-oh7YZqaWr8Pg2DqsbgyO0IXaR3mRUbQM51RxMO5wz1yaI_Ef7bm2o4gJDze0yrt37ykrb7uNUUM6tCY9DErftkMwVCkM%3D&tracking_referrer=time.com

Abstract: "Methane has the second-largest global radiative forcing impact of anthropogenic greenhouse gases after carbon dioxide, but our understanding of the global atmospheric methane budget is incomplete. The global fossil fuel industry (production and usage of natural gas, oil and coal) is thought to contribute 15 to 22 per cent of methane emissions to the total atmospheric methane budget. However, questions remain regarding methane emission trends as a result of fossil fuel industrial activity and the contribution to total methane emissions of sources from the fossil fuel industry and from natural geological seepage, which are often co-located. Here we re-evaluate the global methane budget and the contribution of the fossil fuel industry to methane emissions based on long-term global methane and methane carbon isotope records. We compile the largest isotopic methane source signature database so far, including fossil fuel, microbial and biomass-burning methane emission sources. We find that total fossil fuel methane emissions (fossil fuel industry plus natural geological seepage) are not increasing over time, but are 60 to 110 per cent greater than current estimates owing to large revisions in isotope source signatures. We show that this is consistent with the observed global latitudinal methane gradient. After accounting for natural geological methane seepage, we find that methane emissions from natural gas, oil and coal production and their usage are 20 to 60 per cent greater than inventories. Our findings imply a greater potential for the fossil fuel industry to mitigate anthropogenic climate forcing, but we also find that methane emissions from natural gas as a fraction of production have declined from approximately 8 per cent to approximately 2 per cent over the past three decades."

See also:
http://time.com/4520124/natural-gas-methane-fossil-fuel/

Extract: "The oil, gas and coal industries emit far more methane than previously understood, a finding that could complicate calculations about the speed of climate change and the best ways to address it, according to new research.

Researchers behind the study, published in the journal Nature, found that methane emissions from the oil and gas sector, as well as natural methane emissions from underground, are 60% to 110% higher in total than previously thought.

Scientists have only recently begun to grapple fully with the role methane—the most common chemical in natural gas—plays in contributing to man-made climate change."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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Hefaistos

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Re: Carbon emissions, totals, trends, etc
« Reply #96 on: October 06, 2016, 07:46:40 AM »
...with most of this growth occurring after year 2000.

From the WP article: "...fugitive fossil fuel methane emissions have actually increased since the 1980s by an average of about 24 megatons, or million tons, per year, with much of this growth occurring since the year 2000. At the same time, the study suggests that methane emissions from  wetlands, rice cultivation and biomass burning have fallen."

So, what happened around year 2000?
Fracking got a technological break-through and started to be employed on a large scale:
"In 1997, Nick Steinsberger, an engineer of Mitchell Energy (now part of Devon Energy), applied the slickwater fracturing technique, using more water and higher pump pressure than previous fracturing techniques, which was used in East Texas by Union Pacific Resources (now part of Anadarko Petroleum Corporation), in the Barnett Shale of north Texas.[33] In 1998, the new technique approved to be successful when the first 90 days gas production from the well called S.H. Griffin No. 3 exceeded production of any of the company's previous wells.[37][38] This new completion technique made gas extraction widely economical in the Barnett Shale, and was later applied to other shales.[39][40][41] George P. Mitchell has been called the "father of fracking" because of his role in applying it in shales"
https://en.wikipedia.org/wiki/Hydraulic_fracturing

Seems to me that fracking should be verboten.

Hefaistos

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Re: Carbon emissions, totals, trends, etc
« Reply #97 on: October 06, 2016, 09:35:46 AM »
This might have been mentioned before, but worth reminding about the huge losses of methane from fracking, estimated on average at almost 6% of total production.

"A bridge to nowhere: methane emissions and the greenhouse gas footprint of natural gas"
Robert W. Howarth, 2014

"... estimating the amount of methane emitted to the atmosphere
as a percentage of the lifetime production of a gas
well
(normalized to the methane content of the natural
gas), including venting and leakages at the well site but
also during storage, processing, and delivery to customers.
For conventional natural gas, we estimated a range of
methane emissions from 1.7% to 6% (mean = 3.8%), and
for shale gas a range of 3.6% to 7.9% (mean = 5.8%) [8].
We attributed the larger emissions from shale gas to venting
of methane at the time that wells are completed, during
the flowback period after high-volume hydraulic
fracturing, consistent with the findings of the EPA 2010
report [7]."


AbruptSLR

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Re: Carbon emissions, totals, trends, etc
« Reply #98 on: October 06, 2016, 04:53:08 PM »
The linked The Guardian article quotes Schwietzke as indicating that it is good that methane has a high GWP and a short lifespan, as this means that the climate will respond quickly when we finally start cutting back on anthropogenic methane emissions (other ESLD scientists are just as enthusiastic about high values of ECS, stating that GMST will drop rapidly once we control emissions).  However, per the attached image, most of the new emissions are coming from natural sources (like wetlands), which represent early activation of "slow-response" feedback mechanisms, indicating that the "true" climate system sensitivity this century will likely be higher than ECS:

https://www.theguardian.com/environment/2016/oct/05/fossil-fuel-industrys-methane-emissions-far-higher-than-thought

Extract: "Lead author Stefan Schwietzke, of the University of Colorado and US science agency Noaa, said that methane from fossil fuels had played a significant role in global warming, but the gas’s short lifetime meant acting on it now could pay quick dividends.

“The good news is that reducing methane emissions now will reduce climate forcing in only a few years – it takes much longer for CO2. And since fossil fuel methane emissions are higher than previously thought, the potential to reduce climate forcing from this specific source is also greater,” he told the Guardian."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

Hefaistos

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Re: Carbon emissions, totals, trends, etc
« Reply #99 on: October 06, 2016, 07:56:56 PM »
... most of the new emissions are coming from natural sources (like wetlands), which represent early activation of "slow-response" feedback mechanisms, indicating that the "true" climate system sensitivity this century will likely be higher than ECS:

ASLR, that's a good point, and I'd like to add, that we really don't see any comparable efforts to reign in methane emissions to what's going on in regards to CO2 emissions. On the contrary, natural gas (Methane) still has the false reputation of a 'cleaner' alternative to other FF.

It's also worth reminding, that if one focuses on the shorter time span GWP's of 10 or 20 years, one mustn't forget that methane has as big a role in global warming as CO2. Methane's global
warming potential (GWP) is 108 for the 10 year horizon, 86 for 20 years, and 34 for 100 years.

R.W. Howarth puts it in the following way:
"The IPCC /2013/ further concludes that at the 10-year timescale, the current global
release of methane from all anthropogenic sources exceeds
(slightly) all anthropogenic carbon dioxide emissions as
agents of global warming; that is, methane emissions are
more important (slightly) than carbon dioxide emissions
for driving the current rate of global warming
. At the 20-
year timescale, total global emissions of methane are
equivalent to over 80% of global carbon dioxide emissions.

This difference in the time sensitivity of the climate
system to methane and carbon dioxide is critical
, and not
widely appreciated by the policy community and even
some climate scientists. While some note how the longterm
momentum of the climate system is driven by
carbon dioxide [15], the climate system is far more
immediately responsive to changes in methane "

A bridge to nowhere: methane emissions and the greenhouse gas footprint of natural gas
Robert W. Howarth
https://www.google.se/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0ahUKEwii8auT3sbPAhVCdCwKHWKnCqYQFggeMAA&url=http%3A%2F%2Fwww.eeb.cornell.edu%2Fhowarth%2Fpublications%2FHowarth_2014_ESE_methane_emissions.pdf&usg=AFQjCNFwTn6xMLN8R_pt3Bbz8xeHRvkROA&cad=rja