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It’s all about me (thane)!

Filed under: — gavin @ 12 November 2009

Well, it’s not really all about me. But methane has figured strongly in a couple of stories recently and gets an apparently-larger-than-before shout-out in Al Gore’s new book as well. Since a part of the recent discussion is based on a paper I co-authored in Science, it is probably incumbent on me to provide a little context.

First off, these latest results are being strongly misrepresented in certain quarters. It should be obvious, but still bears emphasizing, that redistributing the historic forcings between various short-lived species and CH4 is mainly an accounting exercise and doesn’t impact the absolute effect attributed to CO2 (except for a tiny impact of fossil-derived CH4 on the fossil-derived CO2). The headlines that stated that our work shows a bigger role for CH4 should have made it clear that this is at the expense of other short-lived species, not CO2. Indeed, the attribution of historical forcings to CO2 that we made back in 2006 is basically the same as it is now.

As is well known, methane (CH4) is the greenhouse gas whose anthropogenic increase comes second only to CO2 in its 20th Century effect on climate. It is often stated that methane is ‘roughly 20 times more powerful’ as a greenhouse gas than CO2 and this can refer to one of two (very different) metrics. If you calculate the instantaneous forcing for an equivalent amount of CO2 and CH4 (i.e. for a 1 ppmv increase in both), you find that the global forcing for CH4 is about 23-24 times as large (depending slightly on the background assumed). Separately, if you look up the Global Warming Potential (GWP) of CH4 in IPCC AR4 (the integrated forcing of a kg of CH4 compared to kg of CO2 over a 100 year period), you get a value of about 25. GWP is used to compare the effects of emissions today on climate in the future. The numbers are only coincidentally similar since the GWP incorporates both the weight ratio and the ratio of effective lifetimes in the atmosphere which roughly cancel for a 100 year time-horizon.

In the Second Assessment report (1995), the GWP for methane was 21, and it was increased in AR4 because of a greater appreciation for the indirect effects of methane on atmospheric chemistry, and in particular its role as a tropospheric ozone precursor (since increasing methane leads to an increase in low level ozone). There is also an indirect effect on stratospheric water vapour where methane oxidation is a significant source of water in an otherwise very dry region. Both tropospheric ozone and stratospheric water vapour are effective greenhouse gases so including these indirect effects made the net effect of methane greater.

In the standard ‘forcings bar chart’ such as seen in Hansen’s papers, or in TAR, or AR4 (figure 2.20), each change in atmospheric composition is given a separate column. Thus ozone and aerosol effects are denoted separately. Starting off with a paper we wrote in 2005, though, a different approach that is perhaps more useful to policy makers has also been adopted. This ‘emissions-based’ viewpoint attributes the forcings to the actual emissions, rather than to the eventual concentration. Thus since some of the ozone increase is related to CH4 emissions, you get to include that under CH4. The other ozone precursors (carbon monoxide and volatile organic compounds) can also now be blamed for a portion of the ozone impact.

This was incorporated into figure 2.21 in AR4, where it is clear that the impact of methane (once some indirect effects are included) is greater than you would have thought based on the ‘abundance’ viewpoint. Note the changes basically only affect the reactive species. When thinking about the various metrics, the emissions-based view is more closely tied to GWP than the traditional abundance-based approach. A big difference is that GWP is looking forward in time, while emission-based forcings are looking back at historical events.

The increasing sophistication when it comes to attribution and GWP is strongly connected to the development of more comprehensive Earth System Models (ESM) in recent years. These are the descendants of the General Circulation Models of the climate that have been developed over the last 30 years, but that now include interactive atmospheric chemistry, aerosols (natural and anthropogenic) and sometimes full carbon cycles in the ocean and land surface. This extra machinery allows for new kinds of experiments to be done. Traditionally, in a GCM, one would impose atmospheric composition forcings by changing the concentrations of the species in the atmosphere e.g. the CO2 level could be increased, you could add more sulphate, or adjust the ozone in the stratosphere etc. However, with an ESM you can directly input the emissions (of all of the relevant precursors) and then see what ozone levels or aerosol concentrations you end up with. This allows you to ask more policy-relevant questions regarding the net effects of a particular sector’s emissions or the impact of a specific policy on climate forcing and air pollution (see here for a discussion).

Our new Science paper (Shindell et al, 2009) expands on some of the earlier work (as was discussed here) and extended consideration of the indirect effects of CH4 and CO (carbon monoxide) to aerosols as well. This is necessary since SO2 requires oxidants to transform to sulphates (and so is affected by the perturbation of the chemistry by other emissions), and it takes into account the competition between nitrates and sulphates for ammonia (which means that there is a small anti-phasing effect – increasing sulphates tends to decrease nitrates and vice versa). When we did this, we found that methane’s impacts increased even further since increasing methane lowers OH and so slows the formation of sulphate aerosol and, since sulphates are cooling, having less of them is an additional warming effect. This leads to an increase in the historical attribution to methane (by a small amount), but actually makes a much bigger difference to the GWP of methane (which increases to about 33 – though with large error bars).

Currently methane levels are relatively stable (despite small upticks in the last two years) and are running below IPCC projections made in 2001 (this of course is good news). However, CH4 is at more than twice its pre-industrial concentration and so still presents a tempting target for emission reductions which, because of our new work and the relatively short lifetime in the atmosphere, will likely be a little more effective at reducing future forcings than previously thought. Given the value of methane as a fuel, it is likely that more of it will be captured (as in this recent story).

CO2, however, is still increasing dramatically despite the slow down in the economy, and so current growth in radiative forcings is dominated by CO2 and that will very likely continue for decades. Despite our increasing appreciation of the role of other forcings (including land use for instance), the overwhelming driver of climate change in the 21st Century will be CO2 increases.

In a follow-up post, I’ll discuss the sources of methane and the implications of the new results for attribution of climate forcing to different sectors (including agriculture), where there have been some very odd (i.e. wrong) recently published numbers.


191 Responses to “It’s all about me (thane)!”

  1. 101
    Aaron Lewis says:

    Re 94: Very true! However, all the carbon for the methane for cattle on pasture comes out of the atmosphere via plants usually without irrigation or synthetic fertilizer. Cattle in a feedlot eat a huge amount of grain grown with large amounts of fossil energy. Thus, cattle on pasture do not add carbon to the bio-cycles. On a full-life cycle basis, the methane from cattle eating grain does add to carbon in the atmosphere.

    One of my very large fears is that sea level rise will drown the industrial complexes that produce agricultural fuels and chemicals resulting in massive reduction of agricultural production and wide spread starvation. Modern agriculture is dependent on fossil carbon. for example, it takes 30 calories of fossil energy to put one calorie of food energy (as California lettuce) on a plate in a NYC restaurant. In the lettuce analysis, the number one consumer of energy is pumping water for irrigation. Number 2 use is the production of chemicals and fertilizer. Number 3 use of energy in lettuce production is field plowing and cultivation. Trucking the lettuce across the country is way down the list. The lettuce analysis puts feeding grain grown on irrigation to cattle in a feedlot in whole different light.

  2. 102
    Hank Roberts says:

    > 94

    Since most of the methane is from the ponds of manure, obviously cows should be kept in open field pasture but fed high quality grain. I doubt this will be popular. But the methane from anaerobic manure ponds is much greater than that from cow burps. Remember there’s been a huge misdirection by the lobbyists to obscure that.

  3. 103
    Doug Sourbeer says:

    It seem that we don’t want to address the root cause of global changes. It will not matter if every livestock operation in the world is shut down. Nor will it matter if India uses coal or not. As long as population growth continues unhindered, (and even aided by mass migrations), polution will be an ever increasing problem. It’s not so much what you do, as how many of you are doing it.

  4. 104
    mike roddy says:

    I’m a distributor for a microprocessor controls company (Entergize.net) that reduces hotel room energy consumption by an average of 35%. You would think every hotel would buy it, especially with tax credits, utility rebates, and energy savings. Payback time is usually about a year. But no- don’t ask me why, though it may be because I’m a bad salesman. The product is only in about 15,000 rooms in the US, but is standard in the rest of the world.

    Re lighting, though, 85% of a hotel room’s energy use comes from the HVAC unit. The rest is fans, TV, and lights. We can control them, too, but it’s minor compared to the heating controls, and normally not cost effective. I’d like to install light shutoffs, and agree that any energy saved is a good idea, but hotels already have flourescents. The action is in software and controls. When a hotel guest leaves, the HVAC shuts off to a setback position. Big, big energy savings nationally are available here.

  5. 105
    Ike Solem says:

    Coal and the other fossil fuels are the main culprits here, right?

    Let’s say you eliminate all meat production outside of the pre-industrial open range model used by everyone from Saharan goat herders to Finnish reindeer drivers, plus some smaller ‘enclosures’ as per the English & European countryside model. What happens to climate change if that’s all you do?

    1) Coal use would continue to expand as developing nations seek the same kind of nation-wide power grids that western nations have enjoyed for decades. Even in the U.S., reliance on coal has skyrocketed, see Jeff Goodell’s Big Coal (2007)

    “Between 1970 and 2000, the amount of coal America used to generate domestic energy tripled…

    Our consumption is easy to justify: cheap power is important to the American economy, the coal industry provides thousands of jobs, and whatever coal’s environmental problems are, at least coal plants are not going to melt down in some radioactive nightmare or increase the risk that some Middle Eastern terrorist will get his hands on a few ounces of plutonium. But this is the logic of the beer drinker who congratulates himself for not guzzling whiskey. It is not the kind of thinking that leads us to change our lives.”

    2) Shortages of crude oil would lead to a move to dirtier liquid fuel sources, from coal gasoline to Canadian tar sand syncrude to Rocky Mountain shale oil. Those sources require large amounts of natural gas to process into fuel, plus huge volumes of fresh water, and leave massive amounts of liquid and solid waste behind.

    The vision of “The Saudi Arabia of Coal” recently pronounced by Senate politicians would require massive public subsidies for coal-to-gasoline production plants – something that has been very well-supported by both the current and past U.S. Presidents. Obama was among the most vocal Senate proponents of the notion, which provides Illinois a means to convert its very high-sulfur environment-unfriendly coal to marketable gasoline. This is probably the true agenda behind Project FutureGen, as the components are all parts of coal-to-gasoline plants and will be sold on at discount after the “demonstration project” is over.

    With no international treaty with obligations to limit carbon emissions, it will now be possible to move forward with these very fossil CO2-intensive energy projects – from Canadian tar sands to Venezuelan heavy oil to Asian liquified natural gas to coal-to-gasoline projects – without having to risk any pesky lawsuits or legal challenges. These delaying tactics serve little other purpose – for example, with the loudly predicted failure of Copenhagen, the State Department won’t have to take back that permit for Canadian tar sand import pipelines.

    The cover under which all this is being done is carbon capture and sequestration, which will allow all these fossil fuels to be burned without emitting any CO2 to the atmosphere, or so the pet institutions of the fossil fuel lobby claim. Despite all that, no prototypes or energy performance figures have ever been released for any CO2 capture project – just wait 24 years, though…

    Not even the Australian business world is buying it any more:

    Coal-fired power using carbon capture and storage will not play a significant part in Australia’s future energy because by the time it is ready – sometime in the 2030s, the Global CCS Institute says – we will have far more cost-effective options.

    Against that backdrop, livestock emissions are a paltry issue – and consider what would happen if fossil fuels were eliminated, but livestock production was held at today’s levels? You’d probably reach a stable steady state within a few decades, especially if all the factory farms and feedlot operations were eliminated. Clearly, the confined operations and waste ponds are the worst culprits – I don’t think sub-Saharan goat farmers and Asian rice farmers have done anything similar. Just pass laws banning those operations, and then the rise in meat prices will be matched by a fall in non-meat foods – 50% of the corn grown in the U.S. is fed right to cattle, pigs and chickens, for example. Reduce the demand one place, reduce prices the other. Or turn it into ethanol if prices go to low.

    P.S. Noone is going to suggest that countries that grow rice take some kind of “carbon credit penalty” for also producing methane, are they? Think about the overall carbon cycle, and it becomes clear that the fossil fuels are the problem, and that focusing on livestock is just a diversionary tactic… or a very shady marketing campaign for whale meat… sometimes, the Norwegians are just plain embarrassing.

    P.P.S. What does “fair dinkum” mean?

  6. 106
    SecularAnimist says:

    Aaron Lewis wrote: “One of my very large fears is that sea level rise will drown the industrial complexes that produce agricultural fuels and chemicals resulting in massive reduction of agricultural production and wide spread starvation.”

    I don’t think you need to worry about that. By the time the sea level rises that much, worldwide mega-drought will have already caused massive reduction of agricultural production and wide spread starvation. When the vast grain-producing regions of North America have become deserts, all the “agricultural fuels and chemicals” in the world won’t be much help.

  7. 107
    SecularAnimist says:

    Ike Solem wrote: “… consider what would happen if fossil fuels were eliminated, but livestock production was held at today’s levels … if all the factory farms and feedlot operations were eliminated.”

    “Livestock production at today’s levels” is absolutely dependent on industrial-scale factory farms, feedlot operations and slaughterhouses, and on abundant, cheap fossil fuel energy. The amount of meat that can be produced sustainably, without those practices, is far less than what is produced today. In the future you envision, animal flesh, milk and eggs would make up a much smaller part of the developed world’s diet (and especially of the “standard American diet”) because there would be less of them produced, at a higher cost. People would eat a much more plant-based diet. Which would be a good development for human well-being, since it would help to reduce the epidemics of preventable degenerative disease that afflict the developed world (and increasingly afflict the developing world as meat consumption there increases).

    As for the developing world, much of the increase in meat production there is tied to copying US-style factory farming practices — with disastrous consequences for the environment, human health, and animal welfare.

    Like the focus on finding ways to keep the world’s vast fleets of cars on the road, the focus on finding some way to maintain diets based on a toxic excess of animal products is wrong-headed and counterproductive.

  8. 108
    Hank Roberts says:

    Moving to agriculture that doesn’t rely on fossil-fueled corn is a good idea (in part because it removes part of the market for coal and petroleum). Salatin’s model shows it can be done — it could have been done in the 1930s, instead of the path we took, and we’d still have small farm towns all across the east and midwest. States like Louisiana and North Carolina did, wisely, pave the little farm roads, making it possible for the small farmers to get to market in the rainy/muddy weason. Someone should write the alternate history.

  9. 109
    Jonathan Mulligan says:

    102, Hank some larger operations are harnessing the methane. It may one day be regarded as beneficial to congregate animal waste to do just that.
    http://www.technologyalliance.ms/strategic-biomass-solutions/alternative-energy/methane-gas-capture.php
    If only sustainability was expected of the the fossil fuel industry then this renewable energy source would be greatly valued.

  10. 110
    Ike Solem says:

    Coal-fired livestock production?

    Secular Animist says that: “Livestock production at today’s levels” is absolutely dependent on industrial-scale factory farms, feedlot operations and slaughterhouses, and on abundant, cheap fossil fuel energy.

    That’s not so – it’s just a restatement of the fossil fuel lobby’s favorite myth, that modern civilization relies entirely on mining ever-dirtier fossil carbon deposits for conversion to fuel, and if we stop we’ll all go back to pre-industrial squalor & starvation. It’s just not true, as any renewable energy expert can tell you – or just look at the dozens of studies that have been done.

    What IS true is that the feed grain delivered to livestock in the United States alone is enough to feed 800 million people. That’s not really the central point either, however…

    How is all that feed grain produced? Industrial technology – ammonia fertilizer, fossil-fueled tractors, electric water pumps run off coal, plus all the fuels used to transport, process and distribute the grain. Going back to animal and human labor is impossible – so are the fossil fuel ‘dieoff’ proponents right?

    More to the point, can we take individual farms and maintain their level of productivity without fossil fuels? Yes. Solar and wind can provide electricity for all growing and processing operations, and solar biohydrogen can be used in the place of natural gas for fertilizer production. You can do this globally, and the sooner the better – so are U.S. agricultural schools looking into this? Not really… their corporate petrochemical partners don’t like the idea at all.

    So, if you can produce the grain without fossil fuels, you can raise cattle without fossil fuels – even in feedlots. However, if agricultural yields drop as precipitation & weather patterns change, than everything must be scaled back. Groundwater pumping can make up for this in some areas, but once the water is gone (or polluted), that’s it.

    Nevertheless, feedlots and factory farms should be banned or vastly scaled back. Essentially, these approaches are just to fatten the cattle – and it’s healthier to bypass the feedlot fattening stage. The meat is leaner and thus pricier, but the feedlot problems (manure, antibiotic overuse, etc.) are avoided. You would probably also see more local distribution and less global trade in “meat products.” Sure, it’s better to avoid meat, but it’s also obvious that it doesn’t have to be a climate problem.

    For example, are sub-Saharan goat herders the big culprits in global warming?

    Definitely not – it’s the so-called “cheap and abundant” coal and dirty crude sources that are the problem, and all the evidence shows that they can be replaced in full with sunlight & wind, direct solar fuels, baseline nuclear capacity, and efficient technology.

    That will require that policy makers start listening to independent & reliable sources of scientific information, instead of to fossil fuel financed lobbyists, think tanks, academics and news media. The main problem there is actually sorting out the honest voices from the fossil fuel industry spokespeople.

  11. 111
    JCH says:

    Assuming grass fed, when a lone cowpie endures its solitary decomposition on the lonesome prairie, is there a lonely guy out there measuring the methane emissions? I do not want to offend Elsie, but her delicate cowpies are wide and deep. Is there no anaerobic level in them, or is the anaerobic number for livestock methane emissions assumed to be solely from confinement environments.

  12. 112
    Hank Roberts says:

    JCH, Google Scholar:

    Speculative guess about search terms, just one try as an example of how to look:

    http://scholar.google.com/scholar?sourceid=Mozilla-search&q=cow+dung+decomposition+methane+content

    One example from results — there’s much research available to read on this, and I’m sure you can do better with a little effort looking into this

    http://dx.doi.org/10.1016/S0038-0717(96)00267-2
    Methane emissions from danish cattle dung pats in the field

    “The total release of CH4, estimated on the basis of these values, from the dung pats produced by a cow during the grazing season in Denmark is only 0.8–4% of the emission likely to result from the same dung production stored as liquid manure during the same period.”

  13. 113
    PHG says:

    Ike,

    “More to the point, can we take individual farms and maintain their level of productivity without fossil fuels? Yes. Solar and wind can provide electricity for all growing and processing operations, and solar biohydrogen can be used in the place of natural gas for fertilizer production. You can do this globally, and the sooner the better”

    Can you clarify what you mean by solar biohydrogen?

    Solar, while useful in some instances, is not that practical for northern latitudes due to
    reduced solar insolation, especially in winter.

    Also, most process’s that I’m aware of require heat/steam how is that generated?

  14. 114
    Hank Roberts says:

    PGH, the answers to broad questions like this can’t be given on a blog in a brief response — you’re asking about an area of research that takes some reading.

    Example of how to look:
    Guessing at search terms in Scholar finds many papers even limiting the search to year 2009:

    http://scholar.google.com/scholar?hl=en&q=farming+without+fossil+fuels&as_ylo=2009

    Just one example from the first page of hits above, a very good read:

    http://www.swcs.org/documents/filelibrary/fwgbook/FWGHanson_A6EBEBD832E83.pdf

    SWCS – Soil and Water Conservation Service

    Again, just an example of what you can find:

    “… statistics are indicative of several trends in United States and world agriculture. Hanson et al. (2008) discussed eight such current trends, including (1) increased land degradation, (2) competing land uses, (3) focus on single ecosystem service, (4) increased farm size, (5) movement toward commercialization, (6) genetic engineering, (7) global markets, and (8) changing social structure.
    In his discussion of the current status and future trends in American agriculture, Ikerd (2009) argued that the current industrial food system is not sustainable. His premise for animal production was that animal agriculture will be needed to help feed the world in the postindustrial 21st century, and most animals in the future will be raised on grass. His polemic — that the current industrial food system is not sustainable is tenable, and it has far reaching implications for sustainable animal-based production in the United States. Other important considerations that must be dealt with to ensure a sustainable animal-based agriculture include global markets, fossil-fuel energy use, and water shortages. Before discussing these impacts, we will first address the issue of sustainability….”

  15. 115
    PHG says:

    Thanks Hank.

    I’m quite new to this commenting thing so I appreciate your patience.

    I’ll check out the references.

  16. 116
    Lawrence Coleman says:

    Here’s the state of play in Australia-climate wise… Many of our major cities are reaching critical levels of water..in fact except for Hobart in Tasmania and Darwin in tehe northern territory every city is struggling..Brisbane has not too long ago been given a much needed top up, but Adelaide in SA is Critical with Perth in WA not far behind, Sydney’s water supply is becomming precarious and Melbourne also. A large farming town west of Brisbane – Toowoomba has it’s reservour dams now less than 9% full and dropping. Australia cannot cope with this trend of drying for much longer. Water desalinisation plants are being built in Queensland but they pose a significant ecological risk to the coastal fisheries eg..high salt concentrations of the plants waste get pumped only a 1 km out to sea assuming the natual currents will distribute the salt. Australia’s longest and most economically important river he Murray is almost dead by the time it reaches victoria and SA. The last two winters at least have been exceptionally mild in the SE queenland area where I live and the heat waves have been far more intense and longer lasting on record. It’s currently 37C outside and in the computer room where I’m typing..talk about a dedicated amateur climate reporter! So this is how CC is affecting us right now in Australia and the long term prognosis isn’t good.

  17. 117
    Richard Steckis says:

    98
    Ray Ladbury says:
    16 November 2009 at 9:35 AM

    “Steckis, every watt of electricity not used saves 3 watts of energy. Increased efficiency matters. It ought to be one thing everyone in the debate on remediation could agree on. Increased efficiency is good for the climate AND for the economy.”

    Ray. Antrhopogenic CO2 production world wide is estimated at about 19GT. Changing domestic energy efficiency by say 3% in one country will make ZERO effective difference to the world wide production of CO2 most of which is generated in construction, mining and manufacturing industries.

    Again Ray, DO THE MATH. The trouble with a lot of you Physicists is that you reduce to x watts not used save y watts energy instead of looking at the big picture and determining the statistical importance of that assessment (with relation to overall energy consumption) in the real world as she is lived in.

  18. 118
    Richard Steckis says:

    Lawrence Coleman says:
    16 November 2009 at 9:45 PM

    “Here’s the state of play in Australia-climate wise… Many of our major cities are reaching critical levels of water..in fact except for Hobart in Tasmania and Darwin in tehe northern territory every city is struggling..Brisbane has not too long ago been given a much needed top up, but Adelaide in SA is Critical with Perth in WA not far behind”

    Lawrence, this is not a climate change problem. This is a population problem. Australia (I live in Perth) has already exceeded the carrying capacity for a human population (estimated by CSIRO at about 10 million). Australia is the second dryest continent on earth and increasing the population will only exacerbate the perception that climate change is the problem instead of the insatiable demands of an ever increasing population.

    You also say:

    “The last two winters at least have been exceptionally mild in the SE queenland area where I live and the heat waves have been far more intense and longer lasting on record. It’s currently 37C outside and in the computer room where I’m typing..talk about a dedicated amateur climate reporter! So this is how CC is affecting us right now in Australia and the long term prognosis isn’t good.”

    It is my understanding that SE QLD has had good rainfalls this year. Northern NSW has had exceptional recent rainfall. Heat is part of our summers or have we forgotten. And this is NOT an example of climate change, it is an example of an anomalous weather event. Is it not amazing that whenever the weather provides record heat it is blamed on climate change but when the record goes the other way that is just natural variation? Please do not let perception cloud judgment.

  19. 119
    CTG says:

    #105 Ike

    “Fair dinkum” in that context is probably best translated as “genuine” or “truthful”.

  20. 120
    Timothy Chase says:

    Ray Ladbury wrote in 98:

    Steckis, every watt of electricity not used saves 3 watts of energy. Increased efficiency matters. It ought to be one thing everyone in the debate on remediation could agree on. Increased efficiency is good for the climate AND for the economy. Hell, Dude, if the US automobile fleet had an average fuel efficiency of ~30 MPG, the country would be self sufficient in energy. I would suggest, Sir, that perhaps it is you who should do the math.

    Richard Steckis responded in 117:

    Ray. Antrhopogenic CO2 production world wide is estimated at about 19GT. Changing domestic energy efficiency by say 3% in one country will make ZERO effective difference to the world wide production of CO2 most of which is generated in construction, mining and manufacturing industries.

    Again Ray, DO THE MATH. The trouble with a lot of you Physicists is that you reduce to x watts not used save y watts energy instead of looking at the big picture and determining the statistical importance of that assessment (with relation to overall energy consumption) in the real world as she is lived in.

    The math…

    Total US CO2 Emitted for 2007: 6103.4 million metric tons
    Fossil Fuel Combustion: 5735.8 million metric tons
    Percent CO2 Due to Fossil Fuel Combustion: 94.0

    … from EPA 430-R-09-004
    INVENTORY OF U.S. GREENHOUSE GAS EMISSIONS AND SINKS:
    1990 – 2007, ES-7 (pdf pg. 30), Executive Summary
    http://www.epa.gov/climatechange/emissions/downloads09/InventoryUSGhG1990-2007.pdf
    http://www.epa.gov/climatechange/emissions/usinventoryreport.html

    World CO2 Emissions for 2007: 28,431,741 thousand metric tons
    US CO2 Emissions: 5,752,289 thousand metric tons
    US Emissions as Percent of Total: 20.2
    List of Countries by Carbon Dioxide Emissions
    http://en.wikipedia.org/wiki/List_of_countries_by_carbon_dioxide_emissions

    Increasing energy efficiency in the US by 3% would save 0.57%. Increasing US energy efficiency by 50% would save 9.49%.

    Energy efficiencies in the US would save money. Energy efficiency strategies would be replicated and energy efficiency technologies would likely be sold to other countries, resulting in higher profits and rates of employment domestically.

    Assuming the percent of world CO2 emissions due to fossil fuel combustion for the world was similarly 94.0%, a 3% increase in energy efficiency in all countries would result in a reduction in world CO2 emissions of 2.82%. A 50% increase in energy efficiency would imply a 47% reduction in CO2 emissions.

  21. 121
    Timothy Chase says:

    CORRECTION to my previous post

    If one were to speak precisely, rather than saying “increasing energy efficiency by [X]” I should have said “reducing energy use by [X]” as this was the actual math used. Calculations specifically in terms of energy efficiency would give you somewhat different figures — although qualitatively the results would be much the same.

  22. 122
    Paul Segal says:

    Hank #112 quoted
    “The total release of CH4, estimated on the basis of these values, from the dung pats produced by a cow during the grazing season in Denmark is only 0.8–4% of the emission likely to result from the same dung production stored as liquid manure during the same period.”

    And that’s probably ignoring what Dung Beetles will do in Australia. Maybe 7 years ago we used to have a bad fly problem with all the cattle around our place on the mid north coast of NSW, then came the Dung Beetles. Now you are lucky to see anything remaining from a cow pat on the ground after more than 2 days, it has been ploughed in by the beetles, almost no flies too. The dung is eaten by the beetle larvae. The introduction of foreign dung beetles was the work of the CSIRO (Aussie dung beetles aren’t built for large dung piles), with the help of farming groups and farmers.

    The other tack is to attack the source of the methane production in cattle. http://www.csiro.au/files/mediaRelease/mr2000/prDigestion.htm

    More recently the CSIRO have also been doing similar work for sheep.

  23. 123
    chw says:

    In 2000~2009, Arctic and Siberia methane levels are also relatively stable: 1850->1890 ppb (a little higher than aggi_2009.fig2.png ~1780ppb, though)
    http://chwu.org/ch4/

    But i am worried about the warming would (soon) trigger mass methane release in these area, as described in:
    http://www.realclimate.org/index.php/archives/2005/12/methane-hydrates-and-global-warming/

  24. 124
    Ray Ladbury says:

    Steckis tells me to look at the big picture. Now, never mind the delicious irony of this coming from a guy who bites like a pitbull on any brain fart coming out of the denialist community. What really matters is that Steckis is reducing the issue to the energy saved by a single CF–utterly ignoring the fact that if we reduce energy consumption, we won’t be building all those new coal-fired power plants that will spew out CO2 for the next 30-50 years…utterly ignoring the fact that increased demand for energy-efficient technologies spurs further development and makes them more affordable…and utterly ignoring the fact that once we pass the point where natural GHG sources kick in with a vengeance, it’s game over.

    Sorry, Steckis, I have done the math, and the math says that small changes by large numbers of people make a big difference. In fact, they can make all the difference for whether we find a solution to global warming or provide our own answer to the Fermi Paradox.

  25. 125
    David Horton says:

    #118 “whenever the weather provides record heat it is blamed on climate change but when the record goes the other way that is just natural variation”. Um, the records aren’t “going the other way” Richard, that is the point. Region after region, month after month, year after year in Australia we keep seeing record high absolute temps, record high averages, record high sequences, record high lows, and so on. Don’t remember too many records being set in the other direction, do you? Oh, and population? Sure, but pressures from population increase on water supply doesn’t negate pressures on water supply from record low rainfalls, record low average rainfalls. In addition we have had record extreme events in storms and floods. And if you were paying any attention to weather patterns you might notice that rainfall in southern Australia is dropping because fronts are constantly being pushed to the south these days as the continent warms. Doesn’t mean you might not get high rainfall in the north of the country as a result of climate change – predicted to, actually. You could not live in rural Australia over the last twenty years without understanding that there has been a fundamental change in climate, and therefore weather patterns.

  26. 126
    dave p says:

    Re 125
    In australia will the tropical rainbelt move further south as a result of climate change? So Northern New South Wales will become like Queensland, and rain will push further in to the central deserts.

  27. 127

    Don’t skeptics ever post here?
    No, seriously.

  28. 128
    David Horton says:

    re 126 There is a trend on the east coast for tropical fish and other marine species to be found further south as waters warm, and on land tropical diseases like Dengue and Ross River fevers seem to be moving south with the associated mosquitoes. I’m guessing that other insect species and presumably land vertebrates are also extending their ranges south, though this would be slower, and I don’t know of studies showing this yet. So there will be a kind of domino effect where Melbourne becomes more like Sydney, Sydney more like Brisbane, Brisbane more like Townsville. I don’t think species movement can happen on the west coast because of the desert which reaches the coast there. And I’m guessing that the desert regions of central Australia will become warmer but not wetter.

  29. 129
    Hank Roberts says:

    To understand the political issues around the recent law forbidding the EPA from addressing controlling methane big agribusiness, this will help. Be patient — read it down to the end. Check the references.

    http://www.grist.org/article/2009-11-10-mainstream-media-cafo-swine-flu-foer/

  30. 130

    Aron#101: Methane from livestock (and us) doesn’t increase the carbon in the
    atmosphere but it does increase its forcing for a decade or so. Consider the
    limiting case where all the CO2 is magically transformed to CH4, the
    carbon is the same, but (ignoring energy spectrum issues) the planet is stuffed.

    Hank#102: According to the Edgar global CH4 emissions database

    http://edgar.jrc.ec.europa.eu/index.php

    methane from manure is about 10% of methane from enteric fermentation.

  31. 131
    Lawrence Coleman says:

    Don’t worry about Stekis..’There is none so blind etc…’..You would think(pardon the pun) that if everything else fails you could at least rely on good ol common sense..case in point. Carl Sagan first opened my eyes to the fragility and depth of the biosphere by the basketball analogy which I’m sure everyone is familiar with. Our Atmosphere is but an extremely thin film of various gasses mainly nitrogen around a massive body. Why can’t Stekis visualise what happens if we keep pumping simply enormous quantities of pullutants into our breathing bubble decade after decade..doesn’t take a rocket scientist to work that one out mate!
    Here I must in all fairness hang my head lower..Australia is the worst polluter and CO2 producer/source per capita in the world as latest findings prove- 4.5 times the global average. Even though the world puffed 2% more CO2 into the air this year (down from 3.5% in preceding years coz of the GFC) we continued to sail ahead as we probably were not as effected by the GFC as most other countries so it was buisness as usual for our factories. So could it be what the world needs to buy us all some time is a continuation of the GFC?

  32. 132

    I am still confused (some people will say this is an inherent conditio).

    Let me post the question as a gedanken experiment.

    Suppose there had never been any global land-based temperature reporting stations. Would the case for AGW be just about as strong anyway?

  33. 133

    Burgy, I think an answer (even a “gedanken answer”) requires redefinition of “global land-based temperature reporting stations,” which to me is a confusing formulation. (How can they be “global” if they are solely “land-based?” And “reporting stations” would seem to refer to individual sites, which “global” really doesn’t–at least, not in the same sense of the word.)

    However–Guy Callendar felt he’d identified an anthropogenic warming signal back in the 30′s. (Consensus on that seems to be that the trend was there, but it wasn’t primarily anthropogenic at that point.) To do that, he basically created his own (tiny) global dataset. And James Hansen (and co-workers, of course) created GISS in order to investigate the AGW hypothesis.

    So, historically, it seems that the AGW hypothesis gave rise to global datasets–which, upon investigation, strengthened the hypothesis.

    In a way, this process negates your presupposition: once one has asked “Hey, I wonder if all this CO2 could be warming our climate up?” it is a natural step (for the right sort of investigator, at least) to create the data set needed.

  34. 134

    Kevin: Thanks for the answer — but it was to a question I did not ask.

    If my question had been “Were the land based temperaure recorders” instrumental in getting the AGW idea rolling, I think you answered “yes.”

    Bi=ut my question is about a hypothetical world — a world in which land based remperature recorders do not exist. Given this world, would the AGW claim be as robust. I glean from your answer that it would not be, in which case how much weaker would it be?

    I have a contact who thinks that the entire IPCC AGW claim — for the most part — starts with and is currently based upon land temperature measures. I think him wrong on this; the questionis — how wrong?

  35. 135
    Marcus says:

    “If my question had been “Were the land based temperaure recorders” instrumental in getting the AGW idea rolling, I think you answered “yes.””

    Be careful how you phrase this: the AGW idea started rolling in the 19th century with Arrhenius, who posited the impact large increases in CO2 could have on global temperatures based on, I believe, theory and some paleo data.

    In this gedanken experiment, where everything about the scientific world is the same except that there is no land-based temperature record, I would argue that only a few things would be weaker:

    1) Attribution is harder with less data. Sea-surface temperature records, ocean heat content, and radiosonde/satellite data might be sufficient, but usually if you have less data it is always hard to have the same amount of certainty.

    2) Climate sensitivity deductions based on the instrumental record: same argument where less data would almost certainly mean broader pdfs (and these pdfs would most likely stretch more on the upper end than on the lower end, since that’s the end that’s hard to pin down anyway). Here, though, there are more paleoclimate and theoretical studies which yield similar answers to the instrumental records.

    3) Any sort of regional temperature matching to impacts: if we don’t know the surface temperatures in a region, it is kind of hard to discuss how things like plant migration are responding to local temperature.

    But really, there’s so much data that is consistent with a warming world besides the land-temperature data, that outside of a few exercises like the above I just don’t see major effects on the core tenets of AGW theory from throwing out the land data set.

    -Marcus

  36. 136
    Hank Roberts says:

    John B, how do you miss this kind of information after being around here for so long? Why not give us your best answer to this friend of yours — surely you can come up with a good response yourself, just by reading the topics here

    For example: http://www.realclimate.org/index.php/archives/2009/04/breaking-the-silence-about-spring/

    and the material mentioned in them, for example
    http://www.earlyspringthebook.com/

    And so much else. Why just post these extremely naive questions from people who haven’t bothered to make any effort to educate themselves — without showing what you’ve already learned and how good an answer you can come up with from your time spent here?

    You’d be a good example for the kids who come here needing homework help.

    Take your guide from this much recommended page:
    http://catb.org/~esr/faqs/smart-questions.html
    Heck, show it to your friend, he could start off just following those suggestions and make great progress.

  37. 137
    Hank Roberts says:

    PS, if his next question is “but what if we didn’t have calendars so we couldn’t tell that there are changes in the timing of the bird migrations and flower opening” — show him a picture of Stonehenge.

    If his next question is “but if we didn’t have rocks” — you can reassure him that he will always have rocks.

  38. 138

    Burgy,

    “Very wrong.” AGW can also be seen in sea-based temperatures (from ships and buoys), borehole temperature records, balloon radiosondes, satellite observations, tree lines moving toward the poles, earlier hatching dates for the eggs of insects/fish/frogs/reptiles/birds, tropical diseases moving into temperate zones, glacier retreat, melting ice caps, more droughts in continental interiors, more violent weather along coastlines, and increased IR opacity of the atmosphere.

  39. 139
    Paddy says:

    I’m often amazed at the lack of thought presented by the vegetarian lobby with regard to methane emissions. They tend to forget that ruminants are not new to planet earth, and as someone pointed out earlier, millions of ruminants used to roam the wild before domestication. Yes domestication, not creation.
    They conveniently assume that uneaten grass would not produce methane in its lifecycle.
    It also seems current practice to compare apples with oranges, 72 times or 88 times CO2 factoring for instance with 20 years the chosen timeframe. A timeframe which is meaningless given the half of methane being 7 years.
    It shouldn’t be forgotten that direct meat and dairy produce is not the only useful result of feed inputs. Possibly because we view the waste as waste and not potential energy or fertiliser, and ignore the leather biofuel etc part of the energy equation.

    A focus on agricultural methane, some 33% of emissions of a gas said to be 18% of the AGW problem makes it a minnow compared to fossil fuel consumption. Comparable with cement production.

    In the last 20 odd years methane levels have increased 100ppb, and should we apply the 20x warming factor this compares well to the ANNUAL CO2 2ppm approx increase we’ve seen recently.

    On top of that we’ll be told cattle produce as much warming as transport, but don’t mention that transport is factored into that equation, double dipping in my opinion. Nor is it particularly fair considering we nearly all eat animal products but only a small proportion of the worlds population have cars or fly in planes.

  40. 140
    mike roddy says:

    Richard Steckis, #118: “most CO2 emissions are caused by construction, mining, and manufacturing”.

    No. Do the math, and check out the EIA tables. The US is different, but not that different. In the US, manufacturing of all products accounts for 14% of our CO2 emissions. Mining of all minerals is a low figure, certainly less than 100 million tons (1.6%), though it’s difficult to find in the tables. Construction emissions are trivial compared to heating and cooling the buildings, and the emissions of construction material manufacturing are contained in the 14% figure.

    The exception is clearcut logging to produce two by fours for home construction (about 200 mmt CO2 annually), but that’s a separate issue that could be solved if we substituted other materials.

  41. 141
    dave p says:

    re 128
    I remember now reading reports a year ago of heavy rainfall in North West Australia, which is normally desert. Has this continued?

  42. 142
    SecularAnimist says:

    Paddy wrote: “I’m often amazed at the lack of thought presented by the vegetarian lobby with regard to methane emissions. They tend to forget that ruminants are not new to planet earth, and as someone pointed out earlier, millions of ruminants used to roam the wild before domestication. Yes domestication, not creation.”

    With all due respect, I am amazed at the lack of thought that goes into equating the environmental impacts of modern, industrialized, fossil-fueled factory farming of animals not merely with the impact of pre-industrial grazing practices, but with the impact of wild ruminants prior to human domestication of animals.

    In the USA alone, more than nine billion animals are raised and slaughtered for food every year, virtually none of them in conditions or on diets that remotely resemble those of pre-industrialized grazed animals, let alone pre-domestication ruminants; and the vast majority of them in fossil-fuel intensive, massively polluting “confined animal feeding operations” a.k.a. industrial factory farms.

    If you want to argue that animal agriculture can be “reformed” or scaled back or regulated or somehow managed so that its impacts are reduced to those of the pre-factory farm era, that’s one thing.

    But it’s an entirely different matter to turn a blind eye to the detrimental effects of industrialized livestock production and pretend that, for example, the impacts of the modern day beef industry in the USA are no different than those of the wild bison population some 10,000 years ago.

  43. 143
    David Horton says:

    #141 No. But NE NSW has had a number of major floods this year.

  44. 144
    Phil Scadden says:

    Paddy, before jumping to conclusions about emissions accounting and double dipping, you could perhaps check out how it is actually done before criticizing?
    http://www.ipcc-nggip.iges.or.jp/public/2006gl/index.html

  45. 145
    Hank Roberts says:

    Geoff noted
    > methane from manure is about 10% of methane
    > from enteric fermentation.

    Good number. I think that’s comparing cowpies (in the pasture) to cow burps — neither is a big issue.

    From high density cow and pig industry operations, it’s big — and measurable, and quantifiable. That was the basis on which EPA had issued a final regulation on reporting.

    http://scholar.google.com/scholar?hl=en&q=methane+from+manure

    I still wonder if this wasn’t partly done to block the development of agricultural methane as an alternative to fossil fuel — to preclude a competitor from developing in the market. The methane-capture-as-fuel systems would merit subsidy both by directly reducing methane, and by replacing fossil fuel use (not to mention improving the smell downwind of the big pig farms).

    I hope some journalist has been working on this. No doubt it’s been written up somewhere. Anyone know the ag journals?

  46. 146
    Steve Fish says:

    Jeff Baranchok (~#127, 17 November 2009 @ 4:20 PM):

    What you ask depends upon what you think a honest skeptic has to say. What do you think? I don’t really expect an answer, but this interests me.

    Steve

  47. 147

    Paddy#139: It wasn’t the vegetarian lobby that wrote Livestock’s Long
    Shadow, but a group within FAO advocating (or at least predicting) increased
    meat production:

    http://www.fao.org/docrep/010/a0701e/a0701e00.htm

    Another estimate of the emissions due to beef in Australia (page vii) puts
    it at double that of aluminium (using the 100 year methane GWP) and this
    estimate includes NO transport or other indirect emissions.

    http://www.energyrating.gov.au/library/details2003-endusereport.html

    As for the “we all eat animal products”, this needs to be quantified. Beef
    provides just 1.3% of global calories (FAOSTAT) but is a driving force
    for deforestation in many places from my country (Australia) to Indonesia
    and South America. All up, livestock is 700 million tonnes
    of biomass that is supported to provide a mere 17% of
    global calories (unevenly) to 330 million tonnes of human biomass.

  48. 148

    Thanks, Marcus for a good answer (particularly your closing paragraph.” I have been telling my friend essentially this answer for some time now.

    Thanks, Barton, for your comments. It seems to sum up the evidences well.

    Hank — I am well aware of the evidences. What I was doing is exploring how important one of these was. I have not seen this addressed as well as Marcus did in his reply. I do appreciate the links and will have a look at them.

    Burgy

  49. 149
    mike roddy says:

    Ray Ladbury, or anyone else, please send me the link or reference for the statement that every watt saved is worth three watts. I’m in the energy efficiency business- hotel room keycard RF systems- and would love to use that information in my marketing. You can reach me at

    greenframe@aol.com

  50. 150
    JCH says:

    “Good number. I think that’s comparing cowpies (in the pasture) to cow burps — neither is a big issue. …”

    Hank, I think it’s the percentage of all livestock methane that is due to manure – all settings. 90% of all livestock methane is burped, and the vast majority of that is from ruminants – cattle, sheep, and goats.

    They spend the majority of their life spans in pastoral settings, and it’s by a fairly wide margin.

    So I would think pastoral burping has to be the largest source of bovine methane.


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