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Comments 12751 to 12800:

  1. Trump's disbelief won't stop dangerous climate change

    Also is talking about Trump's "disbelief" accurate.

    He denies very well backed up evidence on a host of issues and there seems to be no such thing as objective information in Trump's world. Everything is an immediate expression of what best suits his mood at the moment.

    So one moment he can tell the Wall Street Journal that his administration has no tariffs...

    ‘Where Do We Have Tariffs?’ Trump Asks. Here’s a List

    And the next he is crowing about being "Tariff Man"...

    Trump called himself “Tariff Man.” The internet did the rest.

    Trump's reality is largely subjective, the moment it becomes advantageous to him personally to accept the reality of fossil fuel forced climate change he will. The question is if he ever will get to the point of understanding it's also in his interests to effectively address climate change by switching to a carbon neutral energy model.

  2. Trump's disbelief won't stop dangerous climate change

    BeezelyBillyBub @6 , a lot of what you say is true enough, but sometimes "less is more".

  3. Trump's disbelief won't stop dangerous climate change

    So the Republicans claim that climate mitigation policies would "harm the economy".

    They are deluded, and provide no evidence, and in fact the evidence points the other way. Deployment of solar and wind power has helped the economy by providing cheap electricity and increased employment opportunities.

    There is no evidence carbon tax policies have harmed the economies of countries that have deployed them such as the UK.

    Countries also have to obviously balance economic output with maintaining a healthy environment. To focus entirely on the economy is obviously not useful,  yet this is what the White House does consistently,  shown indisputably by its policies and downgrading of even the most light weight and commonsense environmental standards.

    The harm to the economy is coming entirely from the White House and the GOP, with their tariffs causing price increases, constant backtracking on economic announcements spooking the markets and thus causing crashes in the sharemarket, and unfunded tax cuts increasing the deficit, to name but a few things. The White House focus is entirely on short term superficial gains that cannot properly be maintained longer term, and which come with accumulating costs both economic and environmental, most of which get dumped on the general public.

    According to various experts America is now on the brink of an economic recession because of Trumps policies. trends in bonds are a very reliable indicator and they all point toards a recession .

  4. Is Methane Worse than CO2?? | Climate Chemistry

    MA Rodger@11 I see your point and accept your correction on my use of warming potentials where they should be per unit mass and not per molecule. I still maintain that a factor of 100 for methane is more appropriate for the instantaneous effect, because the factor of 86 is for a 20-year period. As long as we maintain CH4 at a high level it is the instantaneous effect that counts. 20- or 100-year periods only matter if we bring CH4 concentrtions down, and we have not, nor is there any indication of that happening soon.

    But I do accept your correction that I should be using warming potentials of 86 or 100 on a per-unit-mass basis and not on a per-unit-molecule basis.

  5. Is Methane Worse than CO2?? | Climate Chemistry

    Evan @4,

    I think your numbers need a little attention. Having first mentioned atmospheric levels of CH4, you state that in terms of climate forcing, CH4 is  "about" 100-times as powerful as CO2 molecule for molecule. You then go on to say "the warming today from methane is about half that of CO2." That isn't correct.

    CH4 has about a quarter the forcing of CO2 (as of 2016), or more accurately 0.507/1.985 = 1/3.9 . The rise in CH4 since pre-industrial is some 1.1ppm(v) (to 2016) and CO2 124ppm(v). That would make the molecule-for-moleule comparison CH4 = 29 x CO2.

    The Global Warming Potential is a measure of the warming resulting from equal weights of emissions of the different gases over a set period. CH4 has a GWP of 86 over 20 years which is only very roughly about 100. As CH4 is 44/16 = 2.75 lighter than CO2, the GWP would have to be divided by that factor to obtain a molecule-to-molecule comparison, and that for tonnes of gas emitted not the molecues floating round the atmosphere.

  6. BeezelyBillyBub at 05:29 AM on 6 December 2018
    Trump's disbelief won't stop dangerous climate change

    It's been 10 years since most people found out about global warming. It's been 24 years since the Conference of Parties. COP24 is where rich and famous people try to solve climate change.
    *Total world energy growth = 14% per decade*

    2007 = 115 Mtoe

    2017 = 135 Mtoe

    20 Mtoe/decade = 14% increase

    Our total energy growth per decade is 14% or 20 Mtoe/10yrs.

    Source: BP 2018 Energy Review, page 8

    https://www.bp.com/content/dam/bp/en/corporate/pdf/energy-economics/statistical-review/bp-stats-review-2018-full-report.pdf

    *Renewable Energy*

    2007 = 1% of total energy use

    2017 = 3.6% of total energy use

    Renewable Growth = 3%/decade

    How long until renewables = 100% energy use?

    *Answer:* never

    Just look at the chart below, do you see the thin dark orange sliver? It will take at least 70 years for that dark orange color to replace all the other colors on the graph, according to Vaclav Smil. By looking at this graph, that doesn't seem like much of a stretch.

    https://lokisrevengeblog.files.wordpress.com/2018/12/bp1.png

    *Emissions*

    2007 = 300 Gtons/yr

    2017 = 334 Gtons/yr

    Growth = 10%/decade

    https://lokisrevengeblog.files.wordpress.com/2018/12/bp4.png

    Source: BP 2018 Energy Review, page 49

    **Runaway Tipping Points = Runaway Mass Extinction**

    Every 10 years = 14% energy growth + 10% emissions growth.

    Many scientists agree with Claire Fyson:

    We must reduce energy emissions 50% in 10 yrs to avoid 1.5 C.

    Many scientists agree with Stefan Rahmstorf:

    We must reduce energy emissions 100% in 20 yrs to avoid 2.0 C.

    Hans Schellnhuber says that cascading runaway hothouse begins when 5 major tipping points are triggered between 1.5 - 2.0 C.

    Cascading only means the triggering of more than one tipping point.

    https://lokisrevengeblog.files.wordpress.com/2018/12/bp3.png?w=696

    Energy emissions/demand are growing between 10-14%/decade

    They must decrease 50%/decade for life on earth to continue.

    Our whole world depends on annual growth of 2% per year. Your job, your bank, your pension, your government all depend on growth.

    We have 3 weeks of riots in France over gas prices. People in the country can't afford higher gas prices, like people in the city can.

    *Water*

    Water shortages could affect 5bn people by 2050, UN report warns

    https://www.theguardian.com/environment/2018/mar/19/water-shortages-could-affect-5bn-people-by-2050-un-report-warns

    By 2020 about 30-40% of the world will have water scarcity, and according to the researchers, climate change can make this even worse.

    http://www.sciencedaily.com/releases/2014/07/140729093112.htm

    With only 7% of the world’s freshwater, China plans to produce 807 million gallons a day from desalination by 2020, roughly quadruple the country’s current capacity.

    http://www.bloomberg.com/news/articles/2015-04-09/china-embraces-desalination-to-ease-water-shortages

    By 2025, an estimated 1.8 billion people will live in areas plagued by water scarcity, with two-thirds of the world’s population living in water-stressed regions.

    http://environment.nationalgeographic.com/environment/freshwater/freshwater-crisis/

    There will be about 1 billion more mouths to feed worldwide by 2025 and global agriculture alone will require another 1 trillion cubic meters of water per year (equal to the annual flow of 20 Niles or 100 Colorado Rivers).

    http://www.interactioncouncil.org/world-confronts-serious-water-crisis-former-heads-government-and-experts-warn-new-report

    UN studies project that 30 nations will be water scarce in 2025, up from 20 in 1990.

    http://www.aljazeera.com/indepth/features/2011/06/2011622193147231653.html

    According to the U.S. Intelligence Community Assessment of Global Water Security, by 2030 humanity’s “annual global water requirements” will exceed “current sustainable water supplies” by 40%.

    http://www.theatlantic.com/international/archive/2012/05/the-coming-global-water-crisis/256896/

    The global middle class will surge from 1.8 to 4.9 billion by 2030, which will result in a significant increase in freshwater consumption.

    http://www.theatlantic.com/international/archive/2012/05/the-coming-global-water-crisis/256896/

    Water demand in India will reach 1.5 trillion cubic meters in 2030 while India’s current water supply is only 740 billion cubic meters.

    http://www.mckinsey.com/client_service/sustainability/latest_thinking/charting_our_water_future

    If current usage trends don’t change, the world will have only 60 percent of the water it needs in 2030.

    http://www.nytimes.com/aponline/2015/03/20/world/asia/ap-world-water-crisis.html?_r=0

    By 2035, the world’s energy consumption will increase by 35 percent, which in turn will increase water use by 15 percent according to the International Energy Agency.

    http://www.worldbank.org/en/news/feature/2014/01/16/will-water-constrain-our-energy-future

    By the year 2040 there will not be enough water in the world to quench the thirst of the world population and keep the current energy and power solutions going if we continue doing what we are doing today.

    http://www.sciencedaily.com/releases/2014/07/140729093112.htm

    The number of people living in river basins under severe water stress is projected to reach 3.9 billion by 2050, totaling over 40% of the world’s population.

    http://www.globalwaterforum.org/2012/05/21/water-outlook-to-2050-the-oecd-calls-for-early-and-strategic-action/

    Compared to today, five times as much land is likely to be under “extreme drought” by 2050.

    http://news.bbc.co.uk/2/hi/science/nature/6068348.stm

    Feeding 9 billion people by 2050, will require a 60 percent increase in agricultural production and a 15 percent increase in water withdrawals.

    http://www.worldbank.org/en/topic/water/overview

    Water demand is projected to grow by 55 percent by 2050 (including a 400-percent rise in manufacturing water demand).

    http://arstechnica.com/science/2012/03/hot-crowded-and-running-out-of-fuel-earth-of-2050-a-scary-place/

    By 2050, 1 in 5 developing countries will face water shortages (UN’s Food and Agriculture Organization).

    http://www.csmonitor.com/World/Global-Issues/2012/1202/Global-water-crisis-too-little-too-much-or-lack-of-a-plan

    Between 2050 and 2100, there is an 85 percent chance of a drought in the Central Plains and Southwestern United States lasting 35 years or more.

    http://www.livescience.com/49794-megadrought-prediction-southwest-plains.html

    If farmers in Kansas keep irrigating at present rates, 69 percent of the Ogallala Aquifer will be gone in 50 years.

    http://news.nationalgeographic.com/news/2014/08/140819-groundwater-california-drought-aquifers-hidden-crisis/

    *Soil*

    Britain facing food crisis as world's soil 'vanishes in 60 years' - Telegraph

    https://www.telegraph.co.uk/news/earth/agriculture/farming/6828878/Britain-facing-food-crisis-as-worlds-soil-vanishes-in-60-years.html

    Only 60 Years of Farming Left If Soil Degradation Continues - Sciam

    https://www.scientificamerican.com/article/only-60-years-of-farming-left-if-soil-degradation-continues/

    We need to protect the world's soil before it's too late - Popular Science

    https://www.popsci.com/topsoil-agriculture-food

    Soil erosion - Food and Agriculture Organization of the United Nations

    http://www.fao.org/docrep/t0389e/t0389e02.htm

    *Just For Fun*

    please note: Mtoe = not your mom's camel toe.

    The only way to mitigate collapse is to carbon tax the shit heck out of meat and the rich.

    They won't do it unless carbon taxes are 100% private.

    They're right, we've been over-conditioned by social media for ideological addiction.

    There is no uncorrupt form of government that has secrets. Secrets are for the rich and gov-tards.

    The left is preventing progress on this issue as well as the right.

    We don't have time for war on 2 fronts, this is it, it's now or never.

    We need 100% private carbon dividends to fund a universal basic income and free health/education in Africa instead of war and slavery.

    I know how to do this because I once learned how to save my allowance as a kid.

    Moderator Response:

    [JH] Please keep it clean.

  7. Is Methane Worse than CO2?? | Climate Chemistry

    nigelj@9 well stated.

  8. BeezelyBillyBub at 05:28 AM on 6 December 2018
    Trump's disbelief won't stop dangerous climate change

    *2030: 50% of emission will come from meat.*
    *2018: 50% of emissions come from the top 10%.*

    Taxing the shit heck out of meat and taxing the top 30% earners down to a median income will reduce emissions 999% more and faster than anything in the last 20 years.

    https://www.reddit.com/r/collapse/comments/a1gbuj/2030_50_of_emissions_will_come_from_meat/

    Moderator Response:

    [JH] Please keep it clean. 

    I also activated the url link. Please learn how to do this yourself by using the appropriate tools contained in the edit box.   

  9. Is Methane Worse than CO2?? | Climate Chemistry

    CBDunkerson and Evan, I think you guys are both right.

    Firstly methane doesn't accumulate on century long timescales the way C02 does, this is not contentious, which is why I didn't mention it. My point was entirely psychological that the low residence times create a false sense of security and for example farmers in NZ have used it as an argument to keep on emitting methane "because it breaks down quickly".

    However methane is still a significant contributor to greenhouse warming if we go on emitting it even if total quantities were stable decade to decade. But like Evan says, its increasing for other reasons, because we are increasing methane emissions at source in terms of fracking, agriculture and breakdown of natural methane sinks in Asia as below. 

    e360.yale.edu/features/methane_riddle_what_is_causing_the_rise_in_emissions

    climate.nasa.gov/news/2668/nasa-led-study-solves-a-methane-puzzle/

    Remember methane also breaks down to small but still very significant quantities of CO2...

  10. Is Methane Worse than CO2?? | Climate Chemistry

    ps.  Actually an exponential effect but the exponent is less than one.

  11. Is Methane Worse than CO2?? | Climate Chemistry

    I think we should be more worried about the instantaeous effect of Methane when compared with Carbon dioxide.  In other words, what would be the short term effect of a greatly increased output of Methane such as may well happen from the Continental Shelf of Russia in the Arctic.  If you look at the chart a short way down in this site  https://en.wikipedia.org/wiki/Greenhouse_gas  You will see that there is 222 times as much Carbon dioxide in the atmospere as Methane and yet the methane has a third as much green house effect as the Carbon dioxide.  The calculation of their relative instantaneous effects is a little difficult since it involves sensitivity or the fact that doubling the gas in question will cause a linear increase in the warming effect (sort of a reversed exponential curve) and that there is a saturation effect above which no more warming will occur but just on a first glance you can see that Methane is far and away a more serious greenhouse gas than Carbon dioxide if the amount vented into the atmosphere spikes.  Even more worrying is that an initial spike will likely lead to further spikes as more reservoirs of Methane go critical.

  12. Trump's disbelief won't stop dangerous climate change

    This is just one more issue for the newly elected House to address starting in January.

    It is mandated by US law that these assessments are done and released, it really doesn't matter if Trump denies them, he also denies such things as evidence from US security agencies on national defence issues.

    Trump White House issues climate change report undermining its own policy

    Trump sides with Russia against FBI at Helsinki summit

    Khashoggi killing: CIA did not blame Saudi crown prince, says Trump

    Donald Trump represents an end run on responsible democratic government, not real democratic representation.

  13. One Planet Only Forever at 03:43 AM on 6 December 2018
    Trump's disbelief won't stop dangerous climate change

    I have an MBA, but I am pretty sure the fundamental economics related to climate science are fairly easy to follow:

    • The competition for superiority relative to others in games based on popularity and profitability (with the ability to benefit from misleading marketing), have developed unsustainable and damaging results. That is because it is cheaper and easier to do things less acceptably or unsustainably (especially if you can keep people from realizing how unacceptable the activity is).
    • Earning wealth for 10 or 20 years is 'increasing wealth'. And earning wealth for one more year is 'earning more wealth'.
    • Being able to personally avoid harmful consequences or significant personal losses when an unsustainable activity ends (when it can no longer be prolonged), is simple 'risk mitigation' which the bigger winners in the pursuit of profit do more successfully than others. Risk mitigation can be done by making sure Others suffer any negative consequences or making sure Others suffer the losses of benefit at the end of the unsustainable activity.

    The burning of fossil fuels is a fundamentally unsustainable activity. The non-renewable resources continue to get harder to get. And eventually nobody will be able to benefit from their burning.

    Burning fossil fuels is also a harmful activity, in many more ways than the production of excess CO2 or methane in the atmosphere.

    So, any society (or person) that has developed perceptions of prosperity or superiority relative to others that are substantially based on benefiting from burning fossil fuels faces a potential serious correction. And without correction of the socioeconomic-political system that allows harmful and unsustainable activity to have a competitive advantage, any innovation is likely to develop new harmful unsustainable activity.

    The portion of the current population benefiting most from the burning of fossil fuels hopes to remain powerful enough to prolong their continued acquisition of more wealth and enjoyment in 'Their lifetime - that 10 to 20 year time frame often applies', and powerful enough to continue to allow harmful and unsustainable activity to continue to have a competitive advantage (every year of personal benefit is 'more personal benefit').

    Protecting the future of humanity, including effective action to limit the climate change impacts on future generations, clearly requires the already more fortunate people who continue to benefit from the global burning of fossil fuels to be unable to protect 'their personal interests and incorrectly developed perceptions of superiority' from the required correction.

    Trump and the New GOP are just part of the many who are now trying to win by Uniting greedier and less tolerant people (united to support each other's unacceptable interests, interests that need to be corrected). Hopefully their undeniable incorrectness on climate science (and so many other matters related to the achievement of the Sustainable Development Goals) will hasten the end of their ability to win the game playing Their incorrect way.

  14. One Planet Only Forever at 02:58 AM on 6 December 2018
    Is Methane Worse than CO2?? | Climate Chemistry

    There is another way to consider the importance of reducing human activity creation of methane, starting now.

    The Paris Agreement lays out the objectives of limiting human impacts to a maximum 2.0 C warming, with the aspiration of limiting warming to 1.5 C. Another way of presenting that is: "The long term warming must not exceed 1.5 C. And the peak impact along the way may be as high as 2.0 C. And if there is a peak above 1.5 C along the way then the impacts will have been reduced to 1.5 C by 2100."

    With that understanding of what needs to be accomplished, there are significant benefits obtained by reducing methane impacts now. Any reduction of methane now will reduce the peak temperature along the way to the 1.5 C end objective. Put another way, reducing methane now would allow for a higher peak of CO2 impact along the way to the end requirement of 1.5 C impact (with the understanding that effective sustainable actions to reduce CO2 will be implemented).

    Of course, everytime this matter of the future temperature impacts is presented, it is important to clearly state that it is unfair for the current generations to benefit by imposing Any global warming related climate change consequences on future generations. Even a 1.5 C warming impact is unfair to the future generations. That means already more fortunate people need to be leading the correction to a sustainable future for humanity. And any more fortunate person who is not doing their part should be effectively corrected by their peers (with every level of the global population demanding that those who are better off than they are behave better than they do - which the Island Nations and other developing nations already clearly being threatened by the climate change impacts are correctly doing by demanding corrective leadership and assistance from the more fortunate).

  15. Is Methane Worse than CO2?? | Climate Chemistry

    I certainly believe, ClimateAdam should cease his channel until he's got the right education. I just posted the following comment on his YT video:

    "A ton of Methane warms the world ten times more than a ton of carbon dioxide does"?
    That's a MYTH!
    Methane is 87 times as potent as CO2 on a 20-year timescale. As we're just approaching the time of no return to keep temps below 2°C we also have to concentrate on CH4 emissions
    https://sites.google.com/site/irelandclimatechange/Atmospheric%20CH4%20history.jpg
    https://sites.google.com/site/irelandclimatechange/2013%20IPCC%20GWP%20%26%20GTP.jpg
    In particular fracking for oil and gas has made methane emissions skyrocketing.
    https://sites.google.com/site/shalegasbulletinireland/all-previous-issues/issue-no-56---may-15-2015#Oil_and_gas_is_sector_top_source_of_US_methane_emissions_ahead_of_agriculture
    https://sites.google.com/site/shalegasbulletinireland/all-previous-issues/issue-no-75---march-1-2016#Global_spike_in_methane_emissions_over_last_decade_likely_due_to_US_shale
    https://sites.google.com/site/shalegasbulletinireland/all-previous-issues/issue-no-83---july-1-2016#US_oil_and_gas_methane_emissions_equivalent_to_14_coal-fired_power_plants
    Why misinforming your audience, ClimateAdam? Maybe you should inform yourself a bit more before coming out with the next myth. If you need more information, don't hesitate to send me a PM.
    Also watch "Scratching the 1.5°C Jazz" https://www.youtube.com/watch?v=9a6JeqX1BHI

    And I will add this link to the comments:

    https://sites.google.com/site/irelandclimatechange/that-s-how-fast-the-carbon-clock-is-ticking

  16. Trump's disbelief won't stop dangerous climate change

    In the video summary that Katharine Hayhoe did for Climate Central where she summarized the Fourth National Climate Assessment, she gives the following logical for speaking hopefully about the future instead of focusing on fear and panic. I found this quote inspirational and logical.

    “Fear and panic are not going to fix this problem [Climate Change]. When we panic it’s really good for motivating short-term action. But short-term action isn’t going to solve Climate Change. To solve Climate Change we need the long-term sustained action over days, weeks, months, years, and decades. And to sustain that kind of action we need hope. We can hope for a better future. Hope that our decisions, the choices we make today, can actually change the future.”

  17. Trump's disbelief won't stop dangerous climate change

    For those of you interested, here is a summary of the Fourth National Climate Assessment by Katharine Hayhoe conducted by ClimateCentral.org.

  18. Is Methane Worse than CO2?? | Climate Chemistry

    CBDunkerson@3 Although an individual methane molecule may go away, I am referring to the net atmospheric concentration, which only goes away if we decrease emissions ... which we are not. Current atmospheric methane concentrations are just under 2 ppm. Molecule for molecule methane has about 100 times the warming potential of CO2. I think that people are not concerned about methane because the argument is that if we decrease its levels the methane goes away on a decadal time scale. But today, with CO2 levels at about 400 ppm, and methane at about 2 ppm with 100 times the warming potential of CO2, the warming today from methane is about half that of CO2. If tomorrow we have the same CO2 and methane concentrations, then tomorrow as well the warming from methane will be about half that of CO2. Like CO2, the atmospheric concentration of methane is increasing. With global population increasing (more people eating rice), and with the standard of living increasing in many parts of the developing world (more people eat meat), it seems likely that methane concentrations will remain high. Therefore, as one methane molecular goes away, another comes along to replace it, so that the net effect is that methane is not going away, but increasing.

    Worse yet, since the start of the industrial revolution, in broad strokes CO2 has increased about 50%, whereas methane concentrations have increased about 300%, and are still increasing.

    I would be greatful if someone can show the error of my logic (seriously, I would be greatful to be shown that my argument here is wrong), but it seems to me that every day that we maintain high methane levels that it does not matter if methane is a "short-lived" greenhouse gas. The real point, I think, is that it is a very potent greenhouse gas whose net effect rivals that of CO2. Just because we can conceptually reduce methane concentrations more easily that we reduce CO2 concentrations does not mean that methane is not a big problem.

  19. Is Methane Worse than CO2?? | Climate Chemistry

    Methane 'goes away' whether we stop emitting it or not.

    If it didn't then the atmospheric methane level would grow every year there was an imbalance between sources and sinks (i.e. the way the CO2 level does) and any level of imbalance would eventually lead to atmospheric doubling. Instead, because atmospheric methane quickly breaks down, to double the amount of atmospheric methane you would need to double the amount of rice production (which, BTW, is actually the largest source of human methane emissions), double the number of livestock, double the number of leaking drill sites, etc... and then keep those elevated levels of these things year after year... all while not decreasing any of the major natural methane sources (i.e. wetlands, termites, wild animals). A virtually impossible task with current technology.

    Thus, the extent of damage which can be done by atmospheric methane is inherently limited in ways that carbon dioxide is not.

    That said, while methane on its own would likely never be a significant global warming problem, with the growing CO2 concentration methane adds a small additional amount of warming which could potentially push us past one or more tipping points that we might have avoided based on CO2 warming alone.

  20. Why does CO2 cause the Greenhouse Effect?! | Climate Chemistry

    michael sweet @20,

    To add a bit more to your comment.

    On the number of collisions etc - The collisions of a molecule in air are measured in microseconds while the the relaxation from vibration of CO2 is in tenths of seconds. So the ratio is in the millions.

    On the pressure broadening - It won't reduce the atmospheric warming as the IR photons are absorbed over a broader spectrum but with less probability at any specific wavelength. But it does leave more gaps, a larger protion of the spectrum which can leak energy to space (if there is no other GHG operating at those broadened wavelengths). And @5, my comment about the "the lack of any other GHGs to fill in the gaps of the electro-magnetic spectrum" didn't consider the relatively minor effect of pressure broadening but was addressing the large parts of the specrum which would have no insulating GHG operating on Mars as there is only CO2 as a GHG in the martian atmosphere.

    On the temperature of Mars - Mars does actually have a greater thickness of CO2 in its atmosphere than Earth, over ten times more. But on its own CO2 would not even compensate for the effects of the diurnal and zonal temperature variations which reduce the average temperature below the simplistic S-B average value.

  21. Is Methane Worse than CO2?? | Climate Chemistry

    nigelj@1 I agree with your assessment. It seems that many are not concerned as much about methane because hypothetically most of it goes away in a matter of decades if we stop emitting it. In the meantime, it is a potent greenhouse gas ... and in the meantime its concentration is increasing not decreasing.

  22. SkS Analogy 16 - Arctic ice, sailboat keels, and wild weather

    william@5 Thanks for the interesting clarification about the dynamics of the large-scale circulation systems.

    nigelj@7 Or as Richard Alley states, there is evidence in the ice-core records of abrupt changes that can occur over a period of years.

  23. SkS Analogy 16 - Arctic ice, sailboat keels, and wild weather

    From abrupt climate change on wikipedia. "An abrupt climate change occurs when the climate system is forced to transition to a new climate state at a rate that is determined by the climate system energy-balance, and which is more rapid than the rate of change of the external forcing." 

    Abrupt can be on anything from decadal to multi century time scales, but its important to realise the paleo history has some huge changes on decadal to single century time scales.This includes abrupt changes as  atmospheric circulation changes, and this tends to be regional, and abrupt sea level rise which can be regional or global.

    By analogy its like tobacoo smoking causes about 20 diseases so which one (or ones) will you get? Nobody knows. Its all a horrible gamble. 

  24. SkS Analogy 16 - Arctic ice, sailboat keels, and wild weather

    Sunspot @2 

    We also have to look at what a summertime ice free Arctic ocean will mean for the stability of the Greenland ice sheet. Instead of a large reflective - and frozen surface - covering the ocean to the north of Greenland, there will be a body of water that absorbs 90% of the summertime sunlight.

    What will relatively warm and humid airmasses moving off the ocean and over northern Greenland in the summer do to the thick ice located there?

    None of these systems we are looking at are stable in the short or even mid term, that is the lesson we are learning from global warming and associated climate change.

  25. Is Methane Worse than CO2?? | Climate Chemistry

    I appreciate that CO2 is the greater problem than methane, but I wonder if the short residence time of methane in the atmosphere creates a false sense of security. The shortness doesn't matter if we just go on emitting methane, which looks likely if humanity goes on consuming meat etc. 

    There is also risk that if temperatures reached 5 degrees, then the melting of permafrost and methane release in Siberia would become irreversible, and would obviously go on for many centuries guaranteeing a lot of methane with probably no way of stopping it. The arctic permafrost is many metres deep. However this simply highlights the need to reduce CO2 emissions.

    www.businessinsider.com.au/hothouse-earth-climate-change-tipping-point-2018-8?r=US&IR=T

  26. SkS Analogy 16 - Arctic ice, sailboat keels, and wild weather

    The Jet stream doesn't shepherd weather systems around the world.  This theory is like the old plum pudding model of the atom.  It is the wall of rising air under the jet stream which marks the boarder between the Polar Hadley Cell and the Ferrel Hadley cell.  Leaving that aside there is a, possibly, more illuminating way of thinking of what is happening and hence what is coming.

    Clasically, with the Artic ocean and surrounding land covered in snow, radiation is reflected back into space.  The air above the Arctic also radiates heat into space, becomes dense and falls to spread out south as it hits the surface of the earth.  This is what powers the Polar Hadley cell.  You all know about the Equatorial Hadley cell and a idler gear (the Ferral cell) is needed in between.  The Polar and Equatorial cells can not meet.  (At mid latitudes the Equatorial Hadley cell causes falling air while the Polar cell at mid latitudes causes rising air).

    When the Arctic ocean is ice free for a significant portion of the summer, we will have rising air over the Arctic and the jet stream, which is now weakening due to the weakening of the Polar Hadley cell should disappear.  Essentially the Ferral cell will extend to the Arctic Ocean.  Climate zones will jump northward in contrast to their present slow creep and with them, the grain growing areas of the Northern Hemisphere with obvious results.

  27. SkS Analogy 16 - Arctic ice, sailboat keels, and wild weather

    Evan @3

    I agree fully, I was referring more to contrarians who use the claim that a few degrees increase in global temperature will have little impacts. When we already see significant changes in climate in many places and very troubling responses in biological communities such as the massive die offs of coral reefs in places like the Great Barrier Reef.

    This temperature increase is averaged over the entire globe and as the meter constantly ticking here indicates, the addition of billions of tons of carbon dioxide to the atmosphere mostly from fossil fuels use also adds an incredible amount of heat to the Earth's surface. Over 2.685 billion Hiroshima bomb heat units since 1998 alone with 4 more being added every second.

    We are reordering how heat and thus weather and climate is distributed around the Earth and this is already having catastrophic impacts.

    The increase in global average temperature may be "slight" in relation to the overall temperature of the Earth, but there is nothing slight in the impacts. And at some point we will hit tipping points that will likely force rapid changes to an Earth that simply will not support many of the current species here now.

    Ecosystem transition on a global scale as has happened in the past with rapid excursions in CO2 and then climate are now referred to as Extinction Level Events.

    Do we really want to create one that we will all be caught in.

    Alarming new study makes today’s climate change more comparable to Earth’s worst mass extinction

  28. SkS Analogy 16 - Arctic ice, sailboat keels, and wild weather

    Doug_C@1 "'Climate change is not a smooth and gradual process to a slightly warmer Earth"

    i'm sure you'll agree that the word "slightly" only applies when you look at global averages, and that there is nothing "slight" about the warming in the Arctic. This is the deceptive nature of uneven warming, especially when the jet stream is driven by temperature differences.

    Sunspot@2 Interesting points you make. Is it the case that the jet stream we grew up with required the cooling of both the Arctic and Greenland? In other words, even if the track of the jet stream is influenced by what becomes the coldest part of the northern hemisphere, will the strength of the jet stream be dictated by the net cooling of the Arctic plus Greenland? In that case it would seem that the loss of Arctic ice will irreversibly decrease the net cooling up there.

  29. SkS Analogy 16 - Arctic ice, sailboat keels, and wild weather

    Paul Beckwith has proposed the alarming notion that, when the Arctic Ocean goes essentially ice-free, and the North Pole is no longer the coldest region in the Northern Hemisphere, that honor will pass to Northern Greenland. The question is, would the Jet Stream follow along, doing its dance with Greenland being the center of circulation, a full 17 degrees from the pole? Paul declined to speculate on what the effect would be on weather patterns, but it's not likely the result would be favorable to the humans.

  30. One Planet Only Forever at 01:58 AM on 5 December 2018
    Ivar Giaever - Nobel Winning Physicist and Climate Pseudoscientist

    purpcran,

    The Club of Rome and Bertrand Russel references sound like attempts to avoid pursuing improved awareness and understanding of climate sceince (and many other matters that matter to the future of humanity).

    The current best awareness and understanding of what is required for the future of humanity is presented in the Sustainable Development Goals which includes the Climate Action Goal.

    The Climate Action Goals are key. More rapidly achieving and improving on them makes it easier to achieve many of the other goals.

    Achieving the Sustainable Development Goals will require Global Cooperation and Collaboration. That may look like Global Government, but what works best to achieve the SDGs, including Globally agreed and enforced corrections of what has developed, is a Good Thing.

    Anyone preferring to prolong already developed, but clearly unhelpful or incorrect beliefs and actions, can be expected seek out and prefer reasons to devisively polarize themselves away from improving their awareness and uderstanding.

    I hope that helps.

  31. One Planet Only Forever at 00:58 AM on 5 December 2018
    But their Emails!

    JP66 appears to be another one of the 'too many' who deliberately divisively polarize themselves away from improved awareness and understanding, to the detriment of the future of humanity.

    Achieving the Sustainable Development Goals, especially the Climate Action Goal, is essential for the future of humanity. Too many people have developed desires that lead them to divisively polarize away from that improved awareness and understanding.

    Division and polarization are clearly a serious problem when they happen regarding 'the constantly improving understanding of things that are understandably evidence based'.

    Division and polarization can also occur regarding matters of personal Opinion or Preference (matters that have no real evidence as a basis, are just matters of belief and faith) such as:

    • what city has the best sports teams
    • what sport is best
    • what type of music is best
    • what type of cuisine is best
    • which spiritual belief is best.

    But those issues are inconsequential to the future of humanity. And all Opinions regarding them need to be respected as long as they do not lead people to act in ways that are harmful to the advancement of humanity to a sustainable better future.

    The correct (and constantly improved) understanding of matters that matter to the future of humanity is what matters. Humanity only advances by improved awareness and understanding.

    New things, like new technological applications, may or may not be advancements. Many people fail to understand that. They incorrectly perceive new technological developments as advacements of humanity.

    Improved awareness and understanding of the sustainability or harmfulness of any activity is always an advancement (no matter how unpopular it is). A developed liking for a belief or way of living can undeniably develop damaging resistance to improved awareness and understanding.

    Unfortunately the developed competitions for 'impressions of superiority relative to others', with popularity and profitability as the measures of acceptability, have resulted in many people developing preferences that lead them to choose to divisively polarize themselves away from improved awareness and understanding.

    The case of climate science, and the divisive polarization of people away from improved awareness and understanding of it, is clear evidence that the socioeconomic-political systems that develop people who choose to avoid improving their awareness and understanding need to be corrected.

    That correction would result in governing and limiting the actions of everyone based on improved awareness and understanding. It would require correction of developed popular incorrect beliefs that unjustly excuse harmful and unsustainable pursuits of personal benefit and profit.

    That means finding ways to correct the people who incorrectly understand important matters, and keeping people who resist improving their awareness and understanding from significantly impacting Others (essentially the correct application of The Rule of Law, and correction of incorrect applications of Law).

    That is the challenge of achieving the Sustainable Development Goals, not just the Climate Action one. The future of humanity requires the challenge of people like JP66, who choose to divisively polarize themselves away from improved awareness and understanding, to be corrected (to learn to change their mind) or be disappointed by being limited contrary to their incorrect developed personal desire to be freer to believe and do whatever they please.

    The freedom to be incorrect regarding matters that matter is harmful to the future of humanity.

  32. 2018 SkS Weekly Climate Change & Global Warming Digest #48

    Link pointing to the source is actually https://news.un.org/en/story/2018/11/1027101

  33. Ivar Giaever - Nobel Winning Physicist and Climate Pseudoscientist

    Eclectic @ 104, wow, the tone you used with Atc was extremely condescending.  Just wow.  I'm sorry that your life sucks that hard.  And even more repulsive is how you go ad hominem for more than half your reply while barely responding to his points, then proceed to lecture him about staying on topic.  Ridiculous behavior, which, I suspect, was motivated by your inability to respond to his points.  If this is at all representative of the scientists of this generation, I can see why people would choose to listen to a random youtube video over "experts".  

    Moderator Response:

    [DB]  Please note that posting comments here at SkS is a privilege, not a right.  This privilege can be rescinded if the posting individual treats adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.

    Please take the time to review the policy and ensure future comments are in full compliance with it.  Thanks for your understanding and compliance in this matter.

    Inflammatory snipped.

  34. Ivar Giaever - Nobel Winning Physicist and Climate Pseudoscientist

    Ahh that's right...nevermind that the Club of Rome specifically mentions global warming as just one element in a larger agenda to exert global control over humanity...

    It might not be scientific evidence, but does it matter at all when the perpetrators have already confessed, in advance, AND THEN PUBLISHED THEIR ENTIRE PLAN??  Arguing about the science seems absurd when no one even discusses this point.  It's sad that so many "scientists" are willing to play the useful idiot in our own enslavement.  Here's a quote from Bertrand Russel:

    “The society of experts will control propaganda and education. It will teach loyalty to the world government, and make nationalism high treason. The government, being an oligarchy, will instill submissiveness into the great bulk of the population…It is possible that it may invent ingenious ways of concealing its own power, leaving the forms of democracy intact, and allowing the plutocrats or politicians to imagine that they are cleverly controlling these forms…whatever the outward forms may be, all real power will come to be concentrated in the hands of those who understand the art of scientific manipulation.”

    Sounds familiar...

    Moderator Response:

    [PS] Sloganeering and politics. "Agenda" is the stuff of conspiracy theorists which are welcome at say WUWT but not here.

  35. But their Emails!

    JP66, @ 21 & 22

    "No. My quote was not previously released."

    Yes it was. I found your quote on several other websites for example here, just by googling it and it certainly forms part of climategate according to them. Whether it does or does not doesn't actually seem that significant anyway, nobody is denying that it's real.

    Why for example would it be wrong to stitch recent temperatures onto a paleo reconstruction? You don't say. I cannot see the problem. Science combines data sets all the time. Nobody has shown a specific problem in the way the data is stitched together, and obviously modern instrumental data is going to be more accurate than modern paleo data.

    There were some criticisms of Manns statistics in the official enquiry, but this is a separate thing. Official reviews of his hockey stick did not say it was fundamentally wrong.

    "and the original paper said it should only be a piece of the picture, but the posters here use it as THE proof."

    Proof of what?

    Like I said additional papers have been done using different approaches and found much the same result of a relatively weak MWP, so things do not hinge around M Manns original paper. This seems to be fairly compelling evidence relating to the MWP. Even if the MWP was warmer than today, what do you think that would prove?

    "I will never post here again because it is apparent this site is against discussion. You just lost points in the war."

    But your problem is you dont discuss things. You have not specifically addressed points people have raised above including myself. Instead you just repeat yourself and go onto new issues, and you just make assertions.

  36. But their Emails!

    No. My quote was not previously released. 

    A theory is valid until one piece of data invalidates it.  1 million papers become irrelevant if data invalidates the hypothesis.

    The hockey stick graph is not a useful bit of data because it is too controversial and is based on a combination of proxy data and thermometer data.  The NAS said it should not have been given the importance it was afforded, and the original paper said it should only be a piece of the picture, but the posters here use it as THE proof.

     

    That is one example of why I remain on the fence.

    People here are just as biased as the people on WUWT.  For a layman interested in parsing the best evidence posters here are not helping.

     

    Moderator Response:

    [DB]  Please learn what constitutes a scientific theory.

    Also please note that posting comments here at SkS is a privilege, not a right.  This privilege can be rescinded if the posting individual treats adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.

    Please take the time to review the policy and ensure future comments are in full compliance with it.  Thanks for your understanding and compliance in this matter.

    Sloganeering snipped.

  37. But their Emails!

    JP66's cited email was part of the tranche hacked years ago.

    Seems unlikely JP66 is reading the latest release, and instead is trawling contrarian blogs.

  38. But their Emails!

    JP66 @ 8 and 9:

    As it stands your drive-by reflects the shoddy behaviour the pointed out in the article. If you are truly interested in the science, and not another muckraker, would you kindly provide directions to the email you cited so we can get more context?

  39. CO2 is coming from the ocean

    scaddenp @13,
    There was the admission from Hairy Turtle @12 that propane was "is not the only type of fuel burned" but that propane was taken "for example" as a fossil fuel. So enumerating the ratios for the different fuels is good to see. Yet the pertinent number from Manning & Keeling (2006) is surely the average ratio of O2:CO2 for total emissions for all fossil fuels. The paper gives it as 1.39, a little lower than the value for propane given @12 as 5:3 or 1.66.
    That 1.39 average value is an average for the 1990s. If you look at CO2 emissions by fuel-type through the years, the figure was dropping from the turn of the century as coal-use made a come-back, dropping from a high of about 1.40 down to 1.36 but subsequently with coal now less used, the ratio has now risen to something like 1.50 in recent years.

  40. Why does CO2 cause the Greenhouse Effect?! | Climate Chemistry

    dkierleber,

    You have asked good questions that are on topic.  I think you have a small misunderstanding that will soon be corrected.  Keep up the discussion till you feel you are informed.  It helps other readers to hear your questions. Everyone looks harder at their understanding.

    I think you are just a little off.  As I understand the physics, it is easy for carbon dioxide molecules to lose the extra vibrational energy they get from IR photons through collisions with other molecules.  Due to the long time before a new photon is released, there are usually thousands or millions of collisions before a photon is emitted.  It is not necessary for a photon to be emitted at the same time as the collision.  The extra vibrational energy ends up as kinetic energy and heats up the atmosphere.

    Because other molecules of CO2 can be put in the excited state by collisions there is always a population of molecules that can emit photons.  Even though most of the molecules do not emit the energy as photons, enough do to keep the system in equilibrium.  At higher temperatures more molecules are in the excited state and more photons are emitted.

    I think line broadening is only a small contribution to the greenhouse effect.  The primary issue is that when CO2 is at low concentrations emitted photons escape to outer space.  At high concentrations of CO2 the photons are absorbed by other CO2 molecules before they can escape. 

    On Mars the CO2 is in a low concentration (measured as grams per liter) even at the surface so the energy escapes to space.  On Earth the escape altitude was about 10.00 kilometers in 1850.  Since then the CO2 concentration has increased about 130 ppm.  That increase caused the escape altitude to increase to about 10.16 km (only about 160 meters).  The lapse rate (the rate of decrease of temperature due to increasing altitude) is about 6C per kilometer.  That means it is about 1C cooler at the new escape altitude.  Less energy is emitted when it is cooler.  In order to preserve conservation of energy, it has to heat up at the new escape altitude so that the same amount of energy is emitted.  This increase then propagates down to the surface. 

    At 10km altitude there is little water vapor in the atmosphere since it is so cold.  CO2 is the main greenhouse gas at that altitude.  Since CO2 is the main gas at the escape altitude it exerts the most control over warming.

    I have digressed a lot from your questions about vibrational energy.  Does this information help?  Unfortunately, I do not know of a good reference. For what it is worth, I teach introductory College Chemistry.  We touch on energy exchange.  I did not take quantum chemistry.  I learned the most about the greenhouse effect reading Skeptical Science for the past 10 years.

  41. SkS Analogy 16 - Arctic ice, sailboat keels, and wild weather

    "A meandering jet stream allows deep troughs and ridges, allowing some areas to get unusually warm while other areas become unusually cold (read here, here, and here)"

    Living in Edmonton Alberta a few years ago in mid winter we had one period where temperatures were well above zero when they could just as easily have been -30 C. While at the same time Eastern Canada and the US all the way down to Florida were in a deep freeze with very cold temperatures.

    January 2014 Weather in Edmonton

    Winter Storm of January 28-29, 2014

    Climate change is not a smooth and gradual process to a slightly warmer Earth, it comes in chaotic jumps and pauses and can have devastating impacts.

    Now living back in BC we've had two consecutive years where much of the province has been under a state of emergency starting with too much water too fast in the springs to not enough in the forests during summer heat waves. Large parts of this province have been consecutively drowned and then burned and we're certainly not alone with this weather chaos that comes as natural systems like the Jet Stream and other global scale systems are destabilizing and moving into a much different state.

    Thousands of homes evacuated, highways closed in B.C. because of flooding

    2018 British Columbia wildfires

     

    Something that will in fact take centuries. No matter what we do we have left chaos for many generations to follow to deal with. And if we don't take this bull by the horns and very soon, the chaotic conditions this creates may overwhelm first complex human society then after a global collapse our species itself.

    David Attenborough - Climate change and extinction 

    And yet we still have politicians here in Canada who demand we keep expanding the extraction and burning of fossil fuels.

    Trans Mountain pipeline should go ahead even if consultation doesn’t end with consensus, Notley says

  42. COP24: UN climate change conference, what’s at stake and what you need to know

    Amazing. The BBC is citing climateactiontracker.org

    => Climate change: Where we are in seven charts and what you can do to help

  43. COP24: UN climate change conference, what’s at stake and what you need to know

    Great article. Many thanks for all that information.

    Scratching the 1.5°C Jazz

     

    => https://www.youtube.com/watch?v=9a6JeqX1BHI

    Moderator Response:

    [DB] Please set image widths to below 500.

  44. CO2 is coming from the ocean

    The language is possibly a little loose here. The detail is in Manning and Keeling 2006 and I see that in the O2 consumption calculation, they used:

    "O2 consumed is calculated assuming full combustion of all fossil fuel
    types, and using O2:CO2 molar ratios for each fuel type from Keeling
    (1988). That is, O2:CO2 is 1.17 for solid fuel; 1.44 for liquid fuel; 1.95
    for gas fuel; and 1.98 for flared gas. (Cement manufacture does not
    consume O2)."

  45. CO2 is coming from the ocean

    Hi,

    So the chemical reaction between hydrocarbons and oxygen are (hydrocarbon + 02 --> CO2 +H20). Lets take propane, for example. When combusting, we get (C3H8 + 5(O2) --> 3(CO2) + 4(H2O)). This article states that "Atmospheric oxygen is going down by the same amount as atmospheric CO2 is going up." From this equation, which I know is not the only type of fuel burned, CO2 is going up by 3 mols for every five mols of O2, so oxygen is burned faster than CO2 is emitted, which is the case for every hydrocarbon. This also doesn't account for impurities found in fossil fuels, like sulfur and nitrogen.

    Im taking the 29 gigatons of CO2 emitted from this article. Doing some stoiciometry, we can find the number of tons of O2 that is being consumed by propane*.

    29 gigatons = 2.9e+16 grams

    2.9e+16 g / 44.01g = 6.5894115e+14 mols C02 produced, rounded to 6.6e+14 for significant figures.

    (6.6e+14 mols CO2/3 mols CO2)(5 mols O2) = 1.1e+15 mols O2 consumed (sig figs)

    1.1e+15 mols O2 is vastly greater than 6.6e+14 mols CO2.

    In 1. Oxygen decrease, you say that the carbon part comes from reduced carbon compounds, and that the oxygen comes from the atmosphere, and I agree that burning fossil fuels uses oxygen from the atmosphere. But what I am not understanding is that O2 is decreasing at the same rate CO2 is increasing. O2 is consumed faster than CO2 is emitted, so O2 should be consumed at a 5:3 oxygen to carbon dioxide, which is not what your articles have been saying. If oxygen is decreasing by 5 ppm per year, CO2 should be increasing by 3 ppm, which is significantly different than the roughly 1:1 ratio suggested.

    Where does this 2/5 discrepancy come from? Is there something I'm missing? If my math or reasoning is wrong, please show me where.

    *I understand that propane is not the only type of fossil fuel burned, and is merely an example used in my argument. There will never be a 1-1 C02 to O2 ration when burning hydrocarbons, as is found in their balanced combustion reactions. The more complex hydrocarbons combust with a higher ratio of O2 to CO2 than propane, and simpler hydrocarbons combust at a lower ratio.

    Thanks for your response.

    B. M.

  46. COP24: UN climate change conference, what’s at stake and what you need to know

    Nice summary John!

    Moderator Response:

    [JH] Thank you, It's also chock full of embedded links to important stuff.  

  47. Why does CO2 cause the Greenhouse Effect?! | Climate Chemistry

    PS I will read the 1971 NASA publication today to see how they explain it.

  48. Why does CO2 cause the Greenhouse Effect?! | Climate Chemistry

    I’m dense and not quite there yet. From Pierrehumbert Principles of Planetary Climate (p 221), “Since energy is conserved, the absorption or emission of a photon must be accompanied by a change in the internal energy state of the molecule. It is a consequence of quantum mechanics that the internal energy of a molecule can only take on values drawn from a finite set of possible energy states, the distribution of which is determined by the structure of the molecule.”

    So molecules can only take on specific vibrational states, constrained by quantum mechanics. A molecule with 2 atoms has only 1 allowed vibrational state (3 x 2 – 5). GHG molecules have more allowed energy (vibrational) states (3 x the # of atoms -5 for linear molecules, -6 for nonlinear ones). But the energy states are still confined to whole multiples of the quanta that excites them. Just like a photon energy must match the energy gap between electron shells in order to be absorbed and boost the electron to a higher shell. The photon could not boost 2 electrons half way to the next shell. Quanta can’t be divided.

    It is this quantum constraint that makes the GH work. If GHGs were excited by any LWR the atmosphere would go crazy. GHG molecules can only absorb energy in narrow bands---they are little receptors tuned to specific frequencies. So loosing part of their constrained vibrational energy via collisional transfer would leave them in a non-allowed quantum state.

    Also from Pierrehumbert (p 227) collisional broadening of the absorption bands occurs because the kinetic energy of the collision is not quantized. So a molecule can borrow some of that energy to be boosted to the next allowed vibrational state by photons whose frequency (and thus energy) would ordinarily be outside their absorption band.

    That is the missing part of MA Rodgers response on why Mars is so cold. The lack of water vapor is a big factor but so is the thin atmosphere---too thin to allow for collisional broadening. On Venus, collisional broadening extends high into the atmosphere. This is explained on the American Chemical Society’s post on Multi-Layer Model.

    Digressing for a bit, in a sufficiently thick atmosphere, non GHG molecules can absorb photons during a collision. Nitrogen in Titan’s cold dense atmosphere, eg. That’s a different process called Continuum Absorption and also happens on Venus.

    So, again, I can see the vibrational energy state of molecules being affected by a collision only if the process involved the emission of a lower energy photon to return the molecule to a lower vibrational state. Of course the problem may be my failure to understand the process and learning difficulties associated with my aging brain. Also, Pierrehumbert likely explains the process in the next 2 chapters but I struggle a bit with a graduate level climate science book. I was hoping for a short cut to understanding this

  49. One Planet Only Forever at 09:06 AM on 2 December 2018
    But their Emails!

    Since the EELI is not the owner of the emails is it possible to legally require them to only present them as full email strings. No partial presentation allowed. And no paraphrasing allowed.

  50. Why does CO2 cause the Greenhouse Effect?! | Climate Chemistry

    dkeierleber @15, I came across this when reading up on the greenhouse effect some time back, appears to be written by a chemistry teacher.

    chemistry.elmhurst.edu/vchembook/globalwarmA5.html

    "Certain gases in the atmosphere have the property of absorbing infrared radiation. Oxygen and nitrogen the major gases in the atmosphere do not have this property. The infrared radiation strikes a molecule such as carbon dioxide and causes the bonds to bend and vibrate - this is called the absorption of IR energy. The molecule gains kinetic energy by this absorption of IR radiation. This extra kinetic energy may then be transmitted to other molecules such as oxygen and nitrogen  (as they bump together) and causes a general heating of the atmosphere. Analogy: Think of a partially stretched "toy slinky" - if you bump the slinky, the energy of the bump is absorbed by the vibrations in the slinky."

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