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Comments 201 to 250:

  1. Comprehensive study: carbon taxes won't hamper the economy

    I recently asked Katharine Hayhoe about this. She said that FFs and economic growth have already begun to decouple, citing this report from California: If this is true, where is the California-sized dent we would expect in Global CO2 levels, and why does the Keeling curve continue to show CO2 level growth at *precisely the same* rate as it did before California enacted these policies?

    Moderator Response:

    [JH] Enacting policies and fully implementing them are two different things.

  2. Comprehensive study: carbon taxes won't hamper the economy

    I dont think there has been much effort to get off FF yet but the past is no reason to say that we cant do so. Especially as renewables get to point where they can compete with FF on price without subsidy. I will willingly concede power/wealth not changing much but no reason to assume that power=FF into the future. I am willing to bet you could draw similar graphs for animals of burden and water wheels which would suddenly go off trends as technology changed. Give it another decade or so especially we inact actually effective policy.

  3. Comprehensive study: carbon taxes won't hamper the economy

    @scaddenp it's not a belief, it's an observation, though I suppose that's not evident from this particular graph.

    This one shows the trend persisting into more recent years. The growth rates of Global Primary Energy production (Global power) and Global GDP accumulated (Global wealth) have remained constant for at least as long as we have been keeping records, and this trend continues unabated despite all our attempts to free ourselves from it.

    There is no evidence in the data that any policy measures, individual actions, or technologies implemented to date have made any difference in fossil fuel consumption on the Global level.


    Moderator Response:

    [DB] Shortened URL and activated hyperlink.

  4. One Planet Only Forever at 14:21 PM on 22 August 2018
    State of the climate: 2018 set to be fourth warmest year despite cooler start

    Mal Adapted,

    The likes of Roy Spencer could learn a lot from Sean Carroll's book "The Big Picture" published in 2016. It is an extensive presentation of the developed improved awareness and understanding of what is going on, including how the human mind works.

    It was a NY Times Bestseller. However, it did have critics, mainly the angry group of evangelical purists that disliked the way that Carroll explains that our current understanding of what is going on in our Universe does not require an Intelligent Designer, and the way he effectively makes the case that it is unlikely that there is a God-being influencing what is going on.

    So the likes of Spencer would not likely learn anything from reading Sean Carroll's book.

    As you say, they have already decided not to be open to improved awareness and understanding. They deliberately limit their scientific methods and critical thinking to the defense of the limited worldview they have personally chosen to try to hold on to and defend.

    Sadly, scientific investigation and critical thinking can be very harmful when it is applied by people who are not open to a holistic worldview (not liking the understanding presented by Sean Carroll), and who are focused on narrow-minded selfish interests (not interested in more altruistically helping to develop a sustainable better future for humanity).

    More people need to develop improved awareness and understanding of what is really going on and strive to help develop a sustainable better future for all of humanity (all of the future generations), rather than seeking excuses for a sub-set of current day humanity getting away with an unsustainable activity that is undeniably harmful to future generations (and harmful to a significant portion of current day humanity).

  5. Sunshine Blogger Award

     I think Tamino's Open Mind blog is worthy of a nomination

  6. Comprehensive study: carbon taxes won't hamper the economy

    Why do you believe that the relationship would continue to exist if we transitioned off fossil fuels? This tells you about the past but it doesnt have to be our future. Not to mention being fairly skeptical log/log plots and estimates of world GDP pre-1700.

  7. State of the climate: 2018 set to be fourth warmest year despite cooler start

    And for further perspective on the what 80N means. The area north of 80N is ~4M sq kms (slightly less). The arctic region is 14.5M sq kms. The area of the arctic ocean is 15.5M sq km. Area of globe is 510M sq km.

  8. Comprehensive study: carbon taxes won't hamper the economy

    It's telling that the study only examines the future evolution of the U.S. economy. Truly, this is a shockingly naïve oversight of epic proportions. 

    "Consider the above plot, which shows the relationship between the atmospheric concentration of CO2 above a baseline of 275 ppm and the world’s total GDP, adjusted for inflation to 1990 dollars (see Garrett, 2012 for details). Data is taken from a mixture of ice cores for older dates and gas samples for newer dates.

    What is immediately evident is that, on a log-log plot, there has been an extraordinarily tight relationship between GDP and CO2 concentrations for at least 2000 years. As long as we look at global scales, each ten-fold increase in GDP has always corresponded with an approximate four-fold increase in excess CO2."


    Moderator Response:

    [DB] Shortened URL and activated hyperlink.  Reduced image width.

  9. State of the climate: 2018 set to be fourth warmest year despite cooler start

    Bob Hoye,

    From the OP:

    "The Arctic has been strikingly warm so far this year, with many areas 3C warmer than the global average."

    But if you want to cherry pick only a tiny fraction (80 North) for only part of the year (summer only) than everything looks great!

    Who gives you your cherries?  I also suspect Steve Goddard.

  10. State of the climate: 2018 set to be fourth warmest year despite cooler start


    According to wikipedia, Roy Spencer who compiles the UAH data is an agw climate change sceptic to some extent, and has strong religious fundamentalist views and has signed declarations that say our climate change is natural.

    Well, Spencer signed An Evangelical Declaration on Global Warming, which states:

    We believe Earth and its ecosystems—created by God’s intelligent design and infinite power and sustained by His faithful providence —are robust, resilient, self-regulating, and self-correcting, admirably suited for human flourishing, and displaying His glory. Earth’s climate system is no exception. Recent global warming is one of many natural cycles of warming and cooling in geologic history.


    We deny that Earth and its ecosystems are the fragile and unstable products of chance, and particularly that Earth’s climate system is vulnerable to dangerous alteration because of minuscule changes in atmospheric chemistry. Recent warming was neither abnormally large nor abnormally rapid. There is no convincing scientific evidence that human contribution to greenhouse gases is causing dangerous global warming.


    Ellipses represent arguments from consequences, boiling down to "mitigation will harm poor people."

    IOW, evidence be damned: AGW can't be a threat because God wouldn't allow it.  By signing this document, Spencer has publicly announced his determination to fool himself, and IMHO has forfeited all scientific credibility thereby.

  11. State of the climate: 2018 set to be fourth warmest year despite cooler start

    I am not sure quite information you think the DMI is giving you, but if that is the only temperature record you look at, then surely you should look at what DMI itself have to say about the record and what it is fit for. Ie it is not a climate data record. Furthermore, if you have watched over a no. of years you will notice that there is very low variability in the mid summer temperatures (generally stuck at just above zero) especially compared to the winter temperatures. Reason? Above 80N is mostly ice. The air temperature above ice is forced to close to 0C or below because the insolation goes into just melting the ice. While the ice persists, temperature will be nearly constant. Looks to me like you are looking for a record that makes you feel comfortable about doing nothing but unfortunately this isnt the one if you understand what it tells you. Did you find the more complete analysis of snow cover statistics that I pointed you to comfortable? Or did you choose not to follow the link because winter snow cover fits what you would like to believe whereas spring and summer are unconfortable?

    Furthermore the extraordinary high temperatures in winter on DMI is by contrast a real cause for concern - linked to other unpleasant weather phenomena.

    Cherry picking one aspect of Greenland ice balance while ignoring the larger picture is also not convincing. I dont suppose your opinions are being "informed" by Tony Heller aka Steve Goddard instead of science?

  12. State of the climate: 2018 set to be fourth warmest year despite cooler start

    Please can people get their facts right before they post stuff on the net (me included). I just feel I wasted a few minutes of my life readings Bobs post about one single unexceptional summer north of 80 degrees.

    Having said that, the heatwave is causing big issues in the arctic sea ice right now

  13. State of the climate: 2018 set to be fourth warmest year despite cooler start

    Bob Hoye,

    The DMI 80N temperature reanalysis you are examining is not presented in a manner that allows a useful understanding of trends in high Arctic temperatures. Recently they have added a page showing the seasonal temperature record and you will note the summer temperatures show no rise. If the data through the year is plotted out as decadal averages (usually 2 clicks to 'download your attachment'), the increase in temperatures through autumn-winter-spring can be plainly seen as can a small reduction in summer temperatures, this due to the melt up in the high arctic now sucking energy out of the climate system.

  14. State of the climate: 2018 set to be fourth warmest year despite cooler start


    Sorry did not wish to be obscure. Full Title:

    Arctic Temperatures

    Daily Mean Temperatures North of 80 degrees North

    Archived, each year, back to 1958.

    Moderator Response:

    [DB] Again, Temperatures North of 80 degrees in the Arctic are not very representative of global temperatures.  However, if you want to look at Arctic temperatures, then you need to compare modern temperatures in the Arctic to those of previous centuries for full context.  From Shi et al 2012:

    "20th century warming reverses a long-term orbitally driven summer cooling and that the mid-and late 20th century temperatures were the highest in the past 2 millennia"

    Shi et al 2012

    The above conclusions and results were confirmed by Werner et al 2018, which also found:

    "the instrumental data suggest much warmer temperatures in the last decade (2006–2015 CE)"

  15. State of the climate: 2018 set to be fourth warmest year despite cooler start

    Lengthy article.

    I keep it simple for myself by following the Danish Met Institute (DMI) stuff. Their temperature of "North of 80" has been below the mean for most of the melt season. Their Surface Mass Balance of ice on Greenland has been well above the mean, and their chart of the rate of melt is shutting down fast. Well, this is on schedule.

    The Canadian Cryogenic chart of NH and NA snow-cover extent for July and into August has been above the mean.

    I think that these numbers are reliable, but my issue for the snow cover is that the charts are not updated every day. Seems to be every ten days.


    Moderator Response:

    [DB] "North of 80" is nowhere near a global metric.  Further, Greenland Ice Sheet (GIS) surface mass balance (SMB) is only a metric pertaining to snowfall additions in the accumulation zone, and do not reflect losses at the lower perimeter edges, in the ablation zone of the ice sheet.  So SMB is a misleading metric and should not be used, even for the GIS itself.

    Per the DMI itself:

    "Over the year, it snows more than it melts, but calving of icebergs also adds to the total mass budget of the ice sheet.

    Satellite observations over the last decade show that the ice sheet is not in balance.

    The calving loss is greater than the gain from surface mass balance, and Greenland is losing mass at about 200 Gt/yr."


  16. Sunshine Blogger Award

    Well done and fully deserved.

    Heres a little thing that has worked for me. I like rock music, but when working I have got into the habit of listening to  classical instrumental music like Bachs or Mozarts piano music. I'ts light sounding,  and not distracting.

  17. State of the climate: 2018 set to be fourth warmest year despite cooler start

    Well UAH, RSS and STAR use MSU to produce temperature records for lower troposphere (think averaging over lower 4km of atmosphere), whereas the surface records are well surface temperature records. Recent discussions of UAH versus RSS at Tamino.

    RSS publish their methods with new release, Spencer and Christy, not so much plus a record of mistakes. See here for some history.

    Their history and political leanings however is not a reason to reject UAH. Perhaps a better way is to compare temperatures from RSS and UAH against say radiosonde data (RATPAC). Difficult but doable. See here from David Piepgrass and draw your own conclusions.

  18. State of the climate: 2018 set to be fourth warmest year despite cooler start

    The biggest difference seems to be between the UAH satellite temperature data and everything else particlualry the RSS data.

    Its hard to see why there's such a difference between UAH and everything else. Why is Roy Spencer right and everyone else wrong? He would need a compelling reason, so what is it? Does anyone have technical knowledge on it? 

    According to wikipedia, Roy Spencer who compiles the UAH data is an agw climate change sceptic to some extent, and has strong religious fundamentalist views and has signed declarations that say our climate change is natural.

  19. Climate change and wildfires – how do we know if there is a link?

    Global warming is different. Switching refrigerants is easy compared to burning fossil fuels without producing CO2. CO2 is not a pollutant, it is simply what you get when you burn fossil fuels. There is no easy fix except to not burn fossil fuels.

  20. 2018 SkS Weekly Climate Change & Global Warming News Roundup #33

    Hi Nigelj

    It is an interesting balance.  If humid air rises from the ocean and blows accross to Greenland, indeed this could result in more snow.  On the other hand, The specific heat of the phase change from water vapor to water is about 5 times as great as the heat of the phase change from ice to water.  In other words, a liter of water condensing out of air which is warmer than the ice it comes in contact with gives out enough heat to melt 5kg of ice.  Moreover, if this contact occurs, let's say, at the top of Greenland, 3km above sea level, and the air is made more dense by the cooling effect of the ice, air density currents are created with the denser air pouring down the sloping ice.  From 3km up to sea level the compression of the air would heat up the air almost 30 degrees C.  Of course it wouldn't actually heat up.  This heat would be given up to the ice, melting more ice.  A fascinating problem in balancing temperature, pressure latent heat and wind direction.  My guess would be more snow initially but at some point hugely increased melting of Greenland.

  21. 2018 SkS Weekly Climate Change & Global Warming News Roundup #32

    Yes, certainly in the UK, it is hot nights in a heatwave that cause the health problems, even if the daytime temperatures are modest compared to some parts of the world. The human body can withstand high temperatures during the day as long as it has a chance to cool down at night. Hot humid nights prevent this.

  22. Water vapor is the most powerful greenhouse gas

    Silbersulfid: No one claims temperature is the only influence on humidity. Everyone agrees that other factors also affect humidity. Your assertion that anyone thinks temperature is the only influence, is a “straw man” argument. That means you constructed a straw man just so you could claim victory in knocking it down.

    Those other factors, plus variations in temperature locally in time and locally in space, plus the probabilistic nature even of the dependence of humidity on temperature, all together are responsible for relative humidity being less than 100% (and more than 100%) often and in many places—even over bodies of water. No one disputes that. Despite all that variation of humidity over time and space, it is perfectly legitimate, sensible, and useful to compute average humidity over time and space.

    Temperature can increase without any of those other factors changing. That increases the water-vapor carrying-capacity of the air everywhere that the temperature has increased—in other words, the relative humidity has decreased. But that reduction is fleeting, because quickly the newly extra carrying capacity is filled by extra water vapor molecules—in other words, the relative humidity quickly returns to whatever it was before the temperature increased. The new presence of more water vapor molecules is described as an increase in absolute humidity. All that happens without changing the variabilities of both relative and absolute humidities across time and space.

  23. 2018 SkS Weekly Climate Change & Global Warming News Roundup #33

    Good comments Swayseeker, but wouldn't evaporation from warming oceans primarily cause more snow to form rather than to melt? 

  24. 2018 SkS Weekly Climate Change & Global Warming News Roundup #33

    On the other hand, in the short term, there could be short periods of severe cooling of the Atlantic as the warmer conditions greatly accelerate the melting of Greenland and the more mobile ice exits the Arctic ocean in larger amounts.  The corollary is that tropical waters will warm up as the heat is not exported to the north with some very nasty stroms as a result.

  25. Water vapor is the most powerful greenhouse gas

    @Eclectic: Ok I see your point, that makes sense. I see that we agree on the topic of water molecules and IR transmission.

    But you say, that "warmer air will contain more water vapor molecules - on average. And on average, more water molecules will reach the high altitudes". But where do you take this wisedom from? There must be a whole lot more factors, which influence the amount of water vapor molecules in air (also called humidity, and relative humidity being the humidity related to the maximum possible humidity for air of a special temperature). I could imagine that wind, cloud coverage and cloud condensation nuclei would influence the humidity of air as well, to just name a few. But I am not originally a meteorologist or a clima scientist, so for weather phenomena you should be way more firm than me. To me it seems just very over-simplified to assume that the humidity is solely a function of temperature and nothing else. It also makes absolutely no sense to me to refer to the "Clausius–Clapeyron Relation", since this relation only describes the maximum capacity of water in air, but not the actual humidity air will have for a certain temperature. So when you never refer to 100% relative humidity (which means that the air actually reached its maximum capacity of water), there is absolutely no use then to mention this relation, and to mention that air can hold more water now. When air never holds is maximum capacity, why mention that the maximum capacity just increased? This seems to be totally irrelevant.

  26. Water vapor is the most powerful greenhouse gas

    Silbersulfid @327 :

    I placed the term "optical density" in quotation marks because it is a term that really belongs in a different field (in certain liquid measurements).  Sorry, if that was leading your thoughts into an unhelpful direction.  I was hoping the term would suggest to you the idea of — how far the Infra-Red photons can penetrate into a volume containing a large number of water vapor molecules.

    At low altitudes, the IR photons can travel only a very short distance before being absorbed by another water molecule.  At sufficiently high altitude (where the inter-molecular distances become extremely large between water molecules) it becomes possible for significant numbers of IR photons to avoid re-absorption and escape to "outer space".

    It is the density of water molecules which controls the IR energy escape.  In other words, it is the absolute distance between molecules.  Therefore it is irrelevant whether the "relative humidity" is a bit higher or a bit lower (at this high altitude).

    Warmer air will contain more water vapor molecules — on average.  And on average, more water molecules will reach the high altitudes where their IR emissions will be lost to space.

    Therefore it is completely unnecessary to have 100% Relative Humidity.  Relative Humidity is irrelevant to the greenhouse mechanism.  It is all a matter of inter-molecular distances.  (And of course, the rate of IR energy loss will be related to the air temperature at this altitude.)

  27. 2018 SkS Weekly Climate Change & Global Warming News Roundup #33

    With ocean warming there is going to be more evaporation and a higher specific humidity and this will increase snow melting. People might find it strange that the albedo of fresh snow is 0.90 or so (it reflects about 90% of solar radiation and only absorbs about 10%), yet the absorptivity of snow can be about 99% (absorbs 99% of the radiation falling on it). The albedo refers to absorptivity of sunlight (solar energy) and the absorptivity here refers to the absorptivity of the usual radiation (about 3 microns to 100 microns in wavelength) from objects on earth. So snow acts almost like a blackbody concerning normal temperature objects around it, absorbing practically all radiation received from surroundings, but is a good reflector of sunlight (reflecting about 95% of solar energy). The atmosphere radiates mostly radiation of wavelengths from about 5 to 8 microns in wavelength and from about above 14 microns. So practically all radiation from the atmosphere is absorbed by snow and most radiation from the sun is reflected by snow. Because atmospheric radiation is increasing I am saying we are going to see rapid melting of snow and ice. I have free Delphi code for night radiative cooling at So solar absorptivity of snow could be about 0.1 and absorptivity for snow for the normal radiation from objects at the earth's surface could be about 0.99. The "downwelling sky radiation code" at the above site could help you determine whether snow will melt at night.

  28. 2018 SkS Weekly Climate Change & Global Warming News Roundup #31

    More fire tornadoes with more water vapour: I want to propose this theory (which I have not seen any site mention): A fire can reach 800 deg C or so. Water vapour and CO2 in the atmosphere absorb radiation of 0.82 to 3.2 microns in wavelength and also in about the 4 to 8 microns range. Now an 800 deg C fire radiates about 36.9% of its radiation in the 0.82 to 3.2 range and about 20.1% of its radiation in the 5 to 8 micron range. With more carbon dioxide and more water vapour in the air the heating of the air by fires could be causing more more convection and therefore oxygen to be supplied to fires and more fire tornadoes.

  29. Water vapor is the most powerful greenhouse gas

    @Eclectic: True, all the water vapor has to be considered, not just the vapor at ground level. But I would not say that relative humidity is irrelevant. Because when you talk of a 'water vapor feedback', you imply that the increased capacity for water in air also will be used. But that does not follow logically.
    We know that relative humidity in higher altitudes is quite low. So when we have, let's say, 5 g/m^3 water capacity in air at a height of 10 km, but we only have a relative humidity of 20% (this would result in 1 g of water per m^3), then what is the effect of increasing the capacity to, let's say, 6 g/m^3? There will be no effect, because increasing the maximum limit (due to a higher temperature) will not automatically rise the water level in the atmosphere. The water has to come from somewhere. And if there would have been water available, it could have evaporated in the air before, because the air was not saturated with a relative humidity of 20%. Or in other words: In order for the water vapor feedback to be logically, you must assume a relative humidity of 100% at all times and all locations. Or you have to provide another law which links the value of relative humidity to temperature only, and thus makes relative humidity a function of temperature only and no other effects.
    To your second paragraph: I think you are mixing up some fundamental different terms. What you mean is the absorbance ( of a material. The absorbance defines, how much radiation will be absorbed by the material. The more molecules there are, the more radiation will be absorbed. How much radiation will be absorbed per molecule is defined by the 'molar attenuation coefficient' (, which is an intrinsic property, and thus will *not* change in higher altitudes. Thus water vapor at ground level and in high altitudes should be equally effectively, at least concerning this parameter.
    What indeed does change with higher altitudes (because with higher altitudes pressure changes as well), is the optical density as a synonym for 'refractive index'. But this index does not specify how much radiation will be absorbed by the material, but rather how fast electromagnetic waves travels through the material.

    @scaddenp: I looked up your reference. I found a graphic in the latest report (AR5): Figure 2.31 (b). It is not a good graphic, considering the fact that the axis label says something different than the description, and that the reverence value for the diagram is never stated. But one can see a trend that the water vapor is rising. This is not very surprising knowing that water vapor is a greenhouse gas and that the global temperature is also rising. But how can you be sure, that the rising water vapor is the effect, and not the cause of the rising global temperatures? When reading the text, though, there is a very interesting statement: "Satellite measurements also indicate that the globally averaged upper tropospheric relative humidity has changed little" (AR5, Chapter This would be at least an indication (but not a prove), that relative humidity is indeed a fixed value and does not fluctuate randomly. The only problem is: This statement is not proven sufficiently. Because when looking up the original source referenced in the AR5 (Shi and Bates, 2011), the authors never make such a statement. Anything I missed, or any other remarks?

  30. Climate change and wildfires – how do we know if there is a link?

    I agree those of us talking about the dangers of climate change have to try to lead by example. I have done some things. I own a small home and drive a small petrol car by choice, and I only use it a couple of times a week. Our public transport is very good. I don't fly very much

    But I don't want to sound sanctimonious. Some of those decisions were made for several reasons, I can be indecisive, and I buy some utter rubbish at times, and my heaters are also not very efficient, and I never get around to doing anything about it. Etcetera.

    However I dont think anyone expects people to cycle or be cold. I loathe being uncomfortable, so its off the agenda.

    But here's another thing. We resolved the ozone problem by using new types of refrigerants, and it was virtuaully entirely an industry issue. Nobody expected people to go without fridges, so we have to keep the climate issue in a similar perspective.

  31. Water vapor is the most powerful greenhouse gas

    There would be doubts about water feedback if measured total precipitable water differed from models. This comparison is discussed in opening observations chapter of the latest ipcc report. German translation is available I believe, so I strongly suggest that you check. 

  32. Climate change and wildfires – how do we know if there is a link?

    alea@17 Quite a change of lifestyle. I understand your points and mostly agree. I do not bicycle because of the dangers, yet we made the change to an EV. Not perfect, not enough, but a step.

    I can't argue against your points from the perspective of people choosing the easy path. This is human nature. I am changing my lifestyle because I feel it is incumbant on those of us who are leading the efforts to do so.

    If people could connect the dots beween their driving and a more difficult life for their children and grand children, I think that would make a big difference in how people responded.

    We also don't know what factors will cause a person to change. We may push gently for years and one day a sequence of factors may come together to cause another person to change. We must set the stage with our actions and keep the pressure on, so that when those opportunities for change come, people are somewhat prepared by positive examples of others, such as what you've been doing.

    Where I respectfully differ from your view is that I see the individual action as paramount. I'm not calking about the effect of one bicycle on the rode versus thousands of cars in reducing air pollution, I'm talking more about setting the example and letting others know that the status quo is not acceptable. At a rollerskating rink where we work, a school group came in for a session and brought their own food for the kids. It inlucded some stuff they liked and some fruits and vegies a lot of the kids did not like. A lot of perfectly good food ended up in the trash. So I stood outside in the dumpster for about 30 minutes digging through the trash pulling out the good food. To me this is the worst transgression in the developed world: to throw away perfectly good food. So here I am driving a modern EV and digging through a dumpster to pull out good food. My wife started personally recylcing stuff at the rink that was being thrown away, and now others help her with the recycling effort. I think that deep down people have a sense of what is right and wrong, and they need to be pushed  in the direction doing the right thing.

    So I really don't disagree with your assessment that it is too easy to do the convenient thing, just saying that there is not time to wait for action to come down from on high. We must act individually if we are going to turn this thing around.

  33. Philippe Chantreau at 10:44 AM on 19 August 2018
    Pluto is warming

    The commenters above only show they have not read the materials below and others related to TSI variations.

    Pnyikos says "More discussion is needed!"

    No, it's not. If the sun's output was to increase enough to cause a temperature increase on Pluto so large that it would be observable from Earth, we might as well kiss our bunnies good-bye. The effect would be seen on Earth first and would be of such concern that discussions about Pluto would be delayed until the emergency abates. There is no way that the sun could warm Pluto and we see nothing on Earth first. That is the height of idiocy. Variations on Pluto are going to tell us things about Pluto, not about Earth. We watch the sun closely from here and its output variations are so minute that we could not effectively measure them before satellites. Get real. The Pluto argument is the most grotesque piece of nonsense ever spewed up by deniers. Only one with no quantitative thinking skills whatsoever could be swayed by such drivel.

  34. Water vapor is the most powerful greenhouse gas

    Silbersulfid @324 :

    When considering the greenhouse effect of water vapor, you need to be interested in the absolute water vapor densities in the upper troposphere — not at the ground-level meteorological stations.  Relative humidity is irrelevant.

    At low altitude, water vapor has a very high "optical density" [to the appropriate Infra-Red wavelengths].  At high altitude, the water vapor density becomes thin enough for IR radiation to escape from the Earth's atmosphere.  The high altitude temperature determines the rate of loss of IR energy.  (A similar mechanism operates for CO2, but at different wavelengths and altitude, natuerlich.)


  35. Climate change and wildfires – how do we know if there is a link?

    Just spotted an error, I meant to say at the beginning that there is a big difference between talking the talk, and walking the walk.

  36. Climate change and wildfires – how do we know if there is a link?

    Evan@10: I personally think there is a big difference between talking the talk (acknowledging the climate change threat and collective responsibility), and talking the talk (making personal lifestyle changes), simply because the former is much easier to do than the latter. I have tried to reduce my carbon footprint by turning the heating right down in winter and compensating by wearing more clothes, using publicv transport where feasible instead of driving, growing my own food, recycling, reducing consumption, and cycling most local journeys and to work (20 mile round trip). The problem is that doing many of these things requires significantly more effort and less comfort, and in the worst case increased risk. I gave up driving back in 2013 and did all journeys by bicycle and/or train. To do this required living a more localised life, it was not feasible to drive 20 miles out and back to a remote area to go on a group walk. I ultimately nearly paid the price with my life whan I was hit by a careless driver and at my worst, was two days from having the life support switched off before I came out of the coma. My experience is the extreme, but even growing your own food, it is much easier to go to a supermarket for your veg than spend many hours of the week toiling away on an allotment, with pests and poor weather periodically threatening to destroy your crop. The second issue is that making those sacrifices entails the tangible drawbacks I mentioned, but any tangible benefits are far from obvious. When I cycle for utility purposes, it makes no difference to the local air pollution or traffic levels, because everyone else is still driving around, the only personal benefit being an increase in fitness and a small monetary saving. Ultimately, to advocate people changing to a lifestyle with a significantly lower carbon footprint, or more sustainable, is equivalent (at least now) to asking them to sacrifice comfort and convenience for no tangible benefit. That is always going to be a hard sell. Things might be different if the whole system was changed to something where sustainability was prioritised instead of money, but we have a long long way to go to even get close to that, and to get there is beyond the power of any one individual, hence many will say the climate change issue is the responsibility of governments and business.

  37. Water vapor is the most powerful greenhouse gas

    Hello guys! I really appreciate that you collect arguments here and discuss about them. Because that is how science should be.

    Now to the topic: What I don't understand at the moment: How can water vapor be a reliable feedback loop for global warming?
    I understand that if the temperature gets hotter, more water can be absorbed by the atmosphere. To be accurate, for every degree (1 °C) of warming (at an operating point of 15°C on earth in average), the air can absorb circa 6% more water (see below for a derivation of this value (*1)). This means: If the global temperature increases by 1°C, the atmosphere can (but not must) hold 6% more water molecules. But when at the same time relative humidity drops by approximately 6%, we have the same amount of water molecules in the air than before the warming.

    Thus, to state this effect as a positive feedback loop, the total amount of water absorbed by air must be coupled only to temperature and no other effects (for example to random distributions due to other unknown or non-considered effects). But looking at meteorological stations, relative humidity changes quit a lot. As a rule of thumb, one can say that relative humidity is in the range of 80% (I looked up several meteorological stations, but this rule of thumb certainly will vary from station to station), but also when looking at the average relative humidity of one year at the same station, relative humidity fluctuates by approximately 10%-points (*2). This would compensate the impact of the increased saturation limit completely. So to me it seems that the feedback loop is just a mathematical model, which does not withstand empirical evidence by measurements of relative humidity.
    But you may prove me wrong. Are there any studies about the (global) relative humidity, which state that it indeed stays constant in average? To me it seems to be a very harsh and unrealistic criterion, that the relative humidity must not fluctuate more than 6% (otherwise this fluctuation would outweigh the feedback effect).
    So how can it be explained that the absolute amount of water in atmosphere is coupled only to temperature, and relative humidity stays constant over time and is not coupled to any other effects?

    (*1): One can calculate the saturation limit of water in air using the formula Rho = Ew / (Rw * T), Rho being the saturation limit [kg/m^3], Rw the specific gas constant of water (461.52 J/(kg * K)) and Ew the pressure for water/steam equilibrium, which is also a function of T, the temperature in Kelvin: Ew = 10^(A-B/(T-C))*1000, A = 7.2326; B = 1750.286; C = 38.1. Linearizing around 15°C (equals 288.15 Kelvin) yields a slope of 6% saturation limit change per 1°C change. When linearizing around an operation point of 0°C or 30°C instead of 15°C, the slope does not change much (only by 1%-point).
    Link 1
    Link 2

    (*2): For example I looked up the meteorological station of Hamburg, which has a nice graph of relative humidity over time. One can see that fluctuation is quite high, even averaged over one year. I also could not see a correlation to temperature at first glance. (Sorry, it's a German source, but you should be able to interpret the numbers nonetheless.)
    Link 3
    Link 4

    Moderator Response:

    [DB] Shortened links breaking page formatting.

  38. Climate change and wildfires – how do we know if there is a link?

    Phillipe@13 and nigelj@14 thanks for your encouragement. I will however, keep holding myself to a tightening standard, because we must. Fortunately in Minnesota 25% of our electricity is nuclear and over 20% is renewable, so driving an EV makes a lot of sense. We've communicated to our architect that low-carbon and low-energy impact is important. He seems to understand, and he even just bought an EV himself two weeks ago.

    Definitely agree about passive solar design.

    It's interesting that what really drove me to buy an EV was when I started writing at SkS about climate change. To me it was simply unacceptable to be writing about the urgent need for change and driving a gas hog. We still have one vehicle that burns gas, but we drive it very little. And our compact tractor burns diesel, but as soon as John Deere comes out with a compact electric tractor we will trade it in. This is one of the big problems is that it takes time to transition, even when one wants to.

    By the way, take a look at CarbonCure, which is an initiative to begin decreasing the carbon footprint of concrete.

    The other point here is to be an example. Hopefully, and I do me hopefully not certainly, as extreme weather events become more common place and more people are affected, more people will be open to the message of our need to reduce our carbon footprint. We have to set examples as soon as we can and as best as we can.

  39. Climate change and wildfires – how do we know if there is a link?

    Philippe Chantreau @13, I agree totally. Theres not much I can add, other than two points.

    1) Humanity is not programmed to think very long term in terms of problems that affect us well in the future, and future generations. We respond best to relatively short term immediate shocks.

    2)I agree government has indeed become very controlled by business lobby groups and the mega rich. I think its happened since the demise of trade unionism, and the rise of  market fundamentalism. That's not to say I idolise trade unions, because I dont,  but things seem to have swung to some sort of market fundamentalist extreme that has become absurd, but cracks are appearing and plenty of economists are now conceding its not working.

    Not all rich people have toxic intent, and many are philanthropists, but all it takes is a few extremist ideologues to exert considerable power in critical areas, like the Koch Brothers. Some families have more wealth than entire countries, and money is power.

    America has no limits on election campaign donations and spending, which means corporations and wealthy business lobbies dominate influence, and the public interest groups struggle to compete. Its hard to see how this changes and theres no organised public outcry, just simmering discontent. Problems like this tend to be solved at the 11th hour when it reaches a crisis point.

    New Zealand has some campaign spending limits and stronger climate policies than America, but I admit theres a long way for us to go.


  40. Climate change and wildfires – how do we know if there is a link?

    Evan @12, I think you are on the right path with your house. I design infrastructure. I dont want to be specific becuase I dont think discussion should be about peoples qualifications, however I know enough to comment on housing and you are on the right track. It would be damn near impossible to build a zero carbon home, so growing trees is a nice way of compensating. I dont see what more you could do.

    I suggest look into passive solar design, because this minimises heat loss and heat gain. It does require thermal mass, and normally a concrete floor  which is carbon intensive, but theres not much that could be done, unless you build a wooden floor overlaid  with natural stone, but this is probably unrealistic.

    But passive solar design can significantly reduce energy costs and sometimes all it takes is a little more glass facing the right way, some thermal mass in the floor as a heat sink, (this does mean not having carpet) good insulation etc, and so it doesn't have to cost significantly  more than a standard home. Of course I sense you have probably thought about all this anyway.

    But this all demonstrates a key point. Individuals cannot solve such a problem as carbon content of concrete. We are reliant on industry to reduce the carbon footprint of products, and to provide clean energy, pushed by government policy. Unfortunately theres a whole industry of climate denialism standing in the way of all this as PC points out.

  41. Pluto is warming

    I have seen no mention that Pluto was closer to the sun in 1988 than in 2002. In fact, according to the Wikipedia entry on Pluto, perihelion came on September 5, 1989. If it is true that, despite this, Pluto warmed up, this calls for further measurements — or a search of the literature for newer temperature measurements.

    Perhaps the following excerpt from  is overly simplistic: " At its warmest, when it is closest to the sun, Pluto can reach temperatures of minus 369 degrees Fahrenheit (minus 223 degrees Celsius)." Perhaps there is a delayed reaction as the planet continues to heat up due to being much closer to the sun than usual. Perhaps the increased temperature as Pluto approaches perihelion has atmospheric effects including a greenhouse effect. More discussion is needed!

  42. Philippe Chantreau at 03:11 AM on 19 August 2018
    Climate change and wildfires – how do we know if there is a link?

    Nigel, you don't see evidence of "huge change" because there isn't any. The depth of the denial and the strength of the entrenched interests are a perfect storm. From studying what happened in Europe in the 30s, I hold very little hope that people will wake up to the reality at hand, at least in the US, where they have been drilled ad-nauseam and where the critical thinking ability of the general population has gone down the tubes in the past 30 years. The propaganda means unleashed in the anglo-saxon world on the subject are simply staggering.

    This is a crisis that would require response on a global scale, global cooperation and a mobilization of the kind we have only experienced in large scale wars before. That turns out to be something impossible to muster for the current human animal. The emotional make up of the human simply has no provision for something like that. If we were attacked by aliens and could go at it with guns, there would be no problem, but this is different. It requires a truly, and almost exclusively cooperative effort. Worse yet, it requires us to exercise restraint in our pusrsuit of material goals, while the current economy is entirely based on frantic consumption of innumerable things that we don't really need and overconsumption of the ones we do need.

    What is hard for me to understand is the rapacity of the hyper rich, who are safe no matter what, but won't give up anything at all for the long term benefit of all. It's pretty obvious that is is even in their interest to do so. Of course most of them can be expected to die within the next 40 years, but still. I believe them, in fact. I believe that they're in a denial so profound as to be absolutely sincere. It is driven by emotion and mostly greed, but sincere nonetheless. 

    Evan, I wouldn't feel too guilty about your carbon footprint. No progress will be accomplished until coal fired power plants are displaced on a large scale. In fact, getting rid of coal burning completely and increasing transportation fuel efficiency standards for all vehicles (yes, even trucks) may be enough in the medium term to buy us time. The personal footprint argument is one used against honest folks by dishonest people; nobody can have an expectation that you'd have to live totally outside of norms, or expand all of your resources in an individual effort; that is not only unreasonable but stupid.

  43. One Planet Only Forever at 03:09 AM on 19 August 2018
    Climate change science comeback strategies

    Improving the awareness and understanding of more people regarding emergent truths is important. It is how humanity truly advances.

    Achieving all of the comeback strategies would be the best way to sustainably change a person's mind, help the person choose to accept the improved awareness and understanding of climate science. And that will happen if they were interested in learning to improve their awareness and understanding of the emergent truths of climate science, no self interests keep them from improving their understanding.

    However, it may also be helpful to test if the person being deal with is interested in improving their awareness and understanding, improving as a human being. Comments in public (including public forums) can benefit bystanders, even if they do not change the mind of the person they are directed at.

    Pursuits of Human Improvement involve developing improved awareness and understanding based on the available evidence and choosing more helpful, less harmful, ways to act based on that constantly improved wisdom.

    A Good way to test a person's interest in improving their humanity is bringing up the UN Sustainable Development Goals and seeing how they respond. If they say that they like any aspect of the goals I use that as my way in to a deeper discussion. All of the goals need to be achieved for any of the goals to actually be achieved. And it is easy to explain how more aggressive corrective Climate Action makes it easier to achieve almost any of the other goals (and that a lack of action makes it harder to achieve them).

    For humanity to have the best possible future, Good Helpful Altruistic Reasoning has to govern and limit all human activity. It would be best if everyone self-governed responsibly.

    Everyone can be helped to improve their way of thinking about things. But, those who resist improving their awareness and understanding need to be identified and be kept from significantly affecting things until their developed high degree of harmful selfishness is helpfully corrected to being more helpfully altruistic.

    I think the following is a good way to make that point. It also addresses challenges about who decides what is good or acceptable. Many people mistakenly believe that any alternative opinion is 'equally valid - equally deserving of consideration'. That way of thinking leads to the belief that the emergent truths developed by improved awareness and understanding must be compromised 'out of consideration for people who prefer to believe other things'.

    I propose two choices for determining if what human action is acceptable or desired, and if a preferred belief needs to be corrected.

    A: Acceptable is - Doing no harm to others and not detrimental to developing a lasting improved future for humanity. Desired is - helping others and helping develop a sustainable future for humanity.
    B: Allow some people to enjoy their lives more by doing things that are understandably detrimental to achieving A, either delaying A or actually causing harm to other humans, and causing harm to other life may be understood to be harming other humans, especially the way that extinction of life forms almost certainly harms the ability of a robust diversity of future humans to sustainably fit into a robust diversity of life.

    A person who understands that A is the proper objective measure of acceptability and what should govern or limit desires can be helped to also understand the unacceptability of compromising A for B at any time in any way.

    This would lead a person to be more open to improved awareness of climate science and the importance of achieving all of the Sustainable Development Goals, especially the climate action goals (the sooner the better for the future of humanity).

    The major detractors of climate science try to prolong or increase the benefit that a portion of current day humanity can obtain from the burning of fossil fuels to the detriment of the entire future of humanity. They are not interested in increased awareness or understanding of the unacceptability of what they have developed a strong desire to personally benefit from. And they really dislike being corrected, or limited regarding their 'belief excused' actions.

    A conversation that includes the consideration how to help develop a sustainable better future for humanity can improve the awareness and understanding of a bystander, even if the conversation does not change the mind of the person directly engaged.

    If the conversation is private, no chance of bystanders learning from it, and I get a sense that the person does not care about the Sustainable Development Goals, I don't bother discussing the climate science. I briefly try to get them to change their mind regarding the future of humanity. And if that fails I express my disappointment about their lack of interest in becoming a more helpful person, and offer to help them if they are interested, then I move on.

    This is similar to what I learned to do as an engineer. My objective was to help people achieve a better result. I learned to test how interested the people I was dealing with were to improving their awareness and understanding of proper (ethical) engineering. I learned to find out if they genuinely wanted the work done properly to protect the public and the environment from the potentially harmful consequences of the desires of people who want something more profitable (faster or cheaper), or if they were simply interested in trying to impress people who wanted more benefit by getting things done faster and cheaper in the hopes that they could make more money that way.

  44. Climate change and wildfires – how do we know if there is a link?

    nigelj@11 very well stated. At least, I agree. Whether or not you like Al Gore, the name of his film "An Inconvenient Truth" was brilliant.

    I have worked hard to change my life to be consistent with our knowledge of Global Warming and Climate Change, but as you noted, it is really hard to do without. We are currently building a house, because we bought property 20 years ago with a 100-year old knock down house within which we've been living for 20 years. But we knew we could not live in forever because of the condition of the house. So I am very concerned about carbon expenditure to build a new house. We will put in geothermal and solar, and are making the house as small as possible, but still, it will have a carbon footprint. We are planning to plant fruit trees to compensate for the carbon emissions and get some fruit. Is that sufficient compensation for the carbon emissions to build the house?

    We sold our truck and bought an electric vehicle, which we drive about 25,000 miles/year, mainly because my wife volunteers at a rollerskating rink. We have no children of our own and she is amazing working with kids. Does working with kids and helping them grow up well justify the carbon expenditure (even EVs have a carbon footprint)? In some sense I open myself up to criticism in a blog like this because I think that one of the main ways I become motivated to change is when people comment on my degree of hypocrisy. i.e., I write about climate change but am I doing my part to justify my admonitions to others?

    But I think your comments nigelj are well stated.

  45. Climate change and wildfires – how do we know if there is a link?

    Evan @10, that is not a rephrasing, it's more a total restructure of the question :) Still, its a good question.

    I think personal upfront experience of weather becoming more extreme has to motivate some degree of action. A slap in the face like this normally motivates change, yet I do not see much evidence of "huge change". There are at least three possible explanations:

    1) General reluctance to change well established habits (laziness)

    2) Climate change is a gradual thing.Frog being slowly boiled alive syndrome.

    3) I think this is the critical one. Fossil fuels are still the cheapest easiest fuel source for many people, and low carbon products are not common or attractively priced. Its human nature to buy the cheapest product that meets immediate needs, and somewhat irrational to do otherwise.

    I deplore battery chicken farming, but I still buy the damn things. I deplore single use plastic bags, and have managed to stop that but it took me a while to get there. I dont think Im a hugely lazy or irresponsible person. On the plus side I have a small fuel efficient car, but this was a relatively pain free decision to make.

    The answer to 3) should be carbon levy and dividend. This puts a price on carbon, and makes petrol unattractive, and low carbon alternatives more price competitive.

    The challenge is then how do we get this carbon fee and dividend policy? Not many people are crying out for it, and not many politicians support it, except for in a few places like British Columbia. I think the reason is over the last 40 years tax has been branded as evil, and as  theft and as the wrong sort of economic policy. Therefore we have made things difficult for ourselves, and I think its going to be hard work changing this mindset. But I try to remain an optimist on it.

  46. Climate change and wildfires – how do we know if there is a link?

    Perhaps I should ask the question another way. Polls say that a little over 50% of the people accept that humans contribute to global warming. Yet IMO far fewer than 50% of the general public are modifying their lives to acknowledge the reality of climate change. For people who already acknowledge climate change as real and our contribution as key, do these extreme weather events move them to start taking stronger action?

  47. Climate change and wildfires – how do we know if there is a link?

    Evan, I think people directly experiencing extreme weather first hand would mostly increase their acceptance of climate change science, especially warmists and fence sitters. I'm assuming here they are convinced the weather is getting more extreme or have seen data to that effect. Once the threat becomes real and perhaps painful, it clears the mind.

    I dont think it would harden anyones attitudes against climate science , unless they are really deep in conspiracy ideation and think its the government altering the weather, in order to bring on one world government . And yes, I have seen comments like this, but it cant be that many people.

    Of course even quite dramatic change probably won't increase acceptance among many of the denialists either, because they just rationalise it away with claims that climate changed before, the data is fake, its just weather. My guess is it would change maybe about half their minds at best. 

    Needs a poll or survey.

  48. Climate change and wildfires – how do we know if there is a link?

    nigelj @5

    That really seems to be the case.

    We had a fairly wet spring and early summer with few wildfires, we were well below the average until recently. The weather warmed up in early July and things dried out. Then we had a series of thunder storms come through that ignited a large number of wildfires. Over 400 in one outburst from what I recall.

    And now because smoke covers so much of the entire region, after the latest thunder storms it is very hard to detect new fires.

    2018 Wildfire season BC 

    "In fact, lightning has already sparked more than 1,300 wildfires in B.C. this year, which is more than any year since 2009. That number is likely to increase as the extended weather forecast calls for continued hot and dry conditions, with the risk of thunderstorms in some parts of the province."

  49. Climate change and wildfires – how do we know if there is a link?

    For those reading and writing comments here a question. Do you think people experiencing extreme climate-related events like wildfires, droughts, and floods firsthand increases their acceptance of climate science or hardens them against it? I'm not offering an opinion, just asking.

  50. Philippe Chantreau at 14:15 PM on 17 August 2018
    Climate change and wildfires – how do we know if there is a link?

    I think that's only part of the story Nigel. In BC, a major factor is the biotic stressors, many of which have been inked to climate change.

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