Climate Science Glossary

Term Lookup

Enter a term in the search box to find its definition.

Settings

Use the controls in the far right panel to increase or decrease the number of terms automatically displayed (or to completely turn that feature off).

Term Lookup

Settings


All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

Home Arguments Software Resources Comments The Consensus Project Translations About Support

Bluesky Facebook LinkedIn Mastodon MeWe

Twitter YouTube RSS Posts RSS Comments Email Subscribe


Climate's changed before
It's the sun
It's not bad
There is no consensus
It's cooling
Models are unreliable
Temp record is unreliable
Animals and plants can adapt
It hasn't warmed since 1998
Antarctica is gaining ice
View All Arguments...



Username
Password
New? Register here
Forgot your password?

Latest Posts

Archives

Recent Comments

Prev  396  397  398  399  400  401  402  403  404  405  406  407  408  409  410  411  Next

Comments 20151 to 20200:

  1. Humidity is falling

    curiousd,  for Modtran using the default tropical setting, at 0 Km altitude in the second section on "atmospheric profile" it shows RH, which I take to be relative humidity.  In the third section under H2O it gives a value of 1.90E+01, unit not specified.  The value for 0 Km under H2O changes to 5.89E+00 for the US Standard Atmosphere, and to 6.24E+00 in the US Standard Atmosphere with a temperature offset of +1 C provided you have the model set to Hold Fixed  "relative humidity" rather than "water vapor pressure".  I have not gone through all of the standard settings with and without constant relative humidity, but it would not take a great effort to do so.

    Clearly with this function, if you offset the surface temperature by the difference between 1976 and today, holding fixed relative humidity in the UChicago version of Modtran, you would automatically adjust for the change in water vapour pressure as well.

    This does create a slight problem if you are trying to calculate radiative forcings, which are the difference in upwelling IR radiation at the tropopause after the stratosphere has reached radiative equilibrium, but before the troposphere has had any feedbacks.  The latter clause means without andy adjustment in H2O vapour presssure.  Technically that means if you are calculating the radiative forcing between 280 ppmv and 400 ppmv the model would need to be set for the relative humidity at an equilibrium temperature for 280 ppmv, and retain a constant water vapour pressure when calculating the the radiative forcing outgoing IR radiation at 400 ppmv.  That in turn would require knowing the offset in temperature from 1976 to the temperature equilibrium.  In practise, and in the absense of historical data (which we probably lack on a global scale for when the when the CO2 level was 280 ppmv), it means assuming a climate sensitivity factor (ie, a temperature change at equilibrium for a given change in radiative forcing) and making successive approximations on the temperature offset.  It also means that the radiative forcing for an increase in CO2 from 280 ppmv to 400 ppmv would be slightly different to that from a decrease from 400 ppmv to 280 ppmv due to the different base H2O vapour pressure.  For small changes in CO2 the difference should be small enough in practise that it can be ignored.

    I should note that there exists a technique for adjusting for stratospheric equilibrium in calculating the strict radiative forcing, which I have seen explained by David Archer.  Unfortunately, I remember neither the explanation, nor the page on which it was located, so I cannot help you with that.  I mention it, however, incase you want to follow it up. 

  2. Neil deGrasse Tyson on science vs. denial

    HK @13, the Isaac Asimov quote is very good. Very relevant to these times.

    Regarding Carl Sagan, I do think we teach quite a lot of science in schools. Although of course we should try to do better.

    However the problem for my generation, and I'm late middle aged, is we weren't taught specifically about  rational, logical thinking, and analysis, and about logical fallacies etc. (I taught myself from books, plus I had a good intuitive grasp).  Obviously science partly teaches these skills, but not all specific elements of them.

    This rational and evidence based analysis helps people evaluate science, especially competing ideas on things like climate change, evolution v creationism, and vaccines etc. It also helps them evaluate political and social issues.This is what is missing for older generations, and I don't think young people get enough of this either. A bit more philosophy needs to be taught in schools as well.

    This is the issue with Trump. He is not rational, although he must be at least reasonably intelligent( although at times I do wonder) and probably studied science at school. The Republican congress is not rational and evidence based. We have to call it out for what it is, because there are big implications for climate among other things. Hilary Clinton had her faults, but her policy approach was essentially rational, in the main.

    Trumps irrationality is on full show with all his environmental policies. I mean it's mind boggling.

    It's particularly concerning because Trumps supporters aren't too rational either, and seem intent in going against their own best "enlightened" self interest. But in the main, they have been tricked into thinking Trump's policies are good for them.

    I agree part of this irrationality is an old anti intellectual streak in western countries. I think there are other contributing factors. Americans are a very "belief" orientated culture with things like conservatism, the constitution, and American values. This has both a good side obviously, and a downside if it becomes irrationally based or too emotive.

    The Iraq weapons of mass destruction controversy has possibly lead to a huge fall in public trust of politicians, intelligence agencies, and the elite in general, and science has become tangled up in this.

    Things like free trade seem good to me, but have some negative side effects that have not been well mitigated. All this erodes confidence in the elite, and logical argument, and leads people back twards irrational gut reaction thinking.

    People have given up on rationality totally, and gone with entrenched beliefs or gut instincts. This is most unfortunate.

    Of course humans are not coldly logical, and instincts do have value. Remember Star Trek? Captain Kirk was a good role model for the perfect balance of rationality and instincts, and emotion. Unfortunately it hasn't caught on with everyone.

  3. Humidity is falling

    Technical Question about Water Vapor Data:

     SpectralCalc has in their Atmospheric Browser section, data on the concentration of water vapor in the atmosphere versus altitude in terms of volume molecular ratio. SpectralCalc uses the 1976  U.S. Standard Atmosphere for this APP. These data can also be plotted graphically and the resulting graph is quite like the corresponding graph in Modtran Infrared Light in the Atmosphere (MILA). Since SpectralCalc states their input is from the 1976 U.S. Standard Atmosphere I suspect the same is true for MILA. 

     For CO2 the present day concentration is 400 ppm whereas in 1976 it was 330 PPM and therefore, to do a SpectralCalc calculation involving present day CO2 one uses a CO2 scale factor of 1.212 instead of one.

     What scale factor relative to the 1976 value should one use, then, for water vapor?

      But water vapor is not a well mixed gas as is CO2 and the measurement would be more complex. Nevertheless: 

      Why don't they - whoever "they" are - "just" go ahead repeat all the 1976 measurements in the present day...(Did they use mostly weather ballons in 1976 ?) ...to compare, by the same methods in the same locations, the1976 average water vapor volume molecular ratios to present day volume molecular ratios?

     That would seem like a good way to quantify the changes between water vapor concentration in 1976 versus now.

  4. Water vapor is the most powerful greenhouse gas

    Technical Question about Water Vapor

    1. SPECTRALCALC has an "atmospheric browser" which will give the user the volume molecular ratio of water vapor in the atmosphere as afunction of altitude for the U.S. Standard Atmosphere.  If one plots that output versus altitude it matches closely the corresponding curve on Modtran Infrared Light in the Atmosphere (MILA).

    2. The SpectralCalc data, (and I suspect also the MILA data) are based  on the1976 U.S.Standard Atmosphere.

    3. I would think it would be informative if "they" would "just" do whatever they did around 1976 once more in the present day to update the U.S. Standard atmosphere.  (Lot of weather ballons, maybe?) Then you would have a direct measurement of the water vapor concentration now  compared directly to 1976 obtained by the same procedures as 1976.

    4.  Another way of putting this: We now know that CO2 is world wide at a 400 ppm level, whereas in 1976 CO2 was at 330 ppm; therefore for a current SpectralCalc calculation involving a present day atmosphere, the scale factor is 1.212 instead of 1 for CO2. What should be the present day scale factor for water vapor? 

  5. Neil deGrasse Tyson on science vs. denial

    Two quotes from two great minds that I think are very relevant for this thread. Poor Isaac and Carl, they must be rotating in their graves right now!

    There is a cult of ignorance in the United States, and there has always been. The strain of anti-intellectualism has been a constant thread winding its way through our political and cultural life, nurtured by the false notion that democracy means that my ignorance is just as good as your knowledge.

    Isaac Asimov

    We have designed our civilization based on science and technology and at the same time arranged things so that almost no one understands anything at all about science and technology. This is a clear prescription for disaster.

    Carl Sagan

  6. It's too hard

    MA Rodger, I calculated for the size of a circular hole, but clearly have also made a major error in the calculation.  Thankyou for the correction.

  7. It's too hard

    andrewrussell @54,

    I would fully concur with the conclusions of Tom Curtis @55 although I'm not in agreement with him on the size of your giant hole.

    I have before been in SkS discussions about how to sequester sea water to reduce Sea Level Rise (SLR), filling up the Caspian Basin, adding dams there and elsewhere to increase storeage, even pumping sea water up onto Antarctica to store it as ice. While I haven't discussed digging a big hole before, the conclusion is ever the same - such schemes would become far to expensive well before they usefully reduce SLR.

    I make your hole 70 x 70 x 10 miles = 200,000 cu km which is the volume of 550mm of SLR. This would be a useful achievement but as you have to consider SLR beyond 2100AD, you are not providing a 50% reduction in peak SLR, rather reducing it by 20%, 25%. While the massive costs of a 50% scheme could be argued against the cost of sea defences/damage from the extra 50%SLR it prevents, that becomes difficult to argue when a scheme tackles less of the problem and the need for major sea defences/damage will continue, abet a couple of foot lower.

    And the best way of tackling SLR is by cutting our emissions. Once that is achieved, the second-best way would be to sequestrate the troublesome atmospheric CO2. This pushes sequestering sea water as a way to reduce harmful sea level pretty-much off the back of the queue.

    One impractical aspect of a hole of this size is its depth. A 10 mile deep hole would be 10x deeper than the deepest open pit and as mentioned @55, 4x deeper than the deepest mineshaft. It would also be 33% deeper than the deepest borehole. Note the temperatures encountered at 7½ miles down were 180ºC which isn't compatable with having a lake on top. However, depth is not essential other than in reducing the geographical footprint of the scheme, which doesn't have to be all in one spot.

    To give some idea of how massive the digging effort would be, it would require 55,000 copies of the largest excavation machine in the world working for a century to dig such a hole. Happily, this particular machine is an electric vehicle (although sadly being used to dig coal) yet it would take a massive amount of electricity to dig the hole if this technology was used. One of the 55,000 machines uses 65.5MW. If it was fossil-fuelled electricity, at current levels of carbon footprint for electricity (100g/kwh) and assuming the giant digger will be working 24/7 to excavate 100,000cu m/day, for all 55,000 diggers we would be talking 80Gt(C) of CO2 emissions, or 8 years of today's global emissions, which at 550ppm/doublingCO2, 2.3m(SLR)/ºC AGW and ECS=3ºC yields 660mm resulting SLR (at equilibrium). Using renewable electricity is thus an essential requirement for such a scheme.

  8. Neil deGrasse Tyson on science vs. denial

    Wol @10, rationality is not limited to science.  Indeed, it could not be.  Were we not capable of rationality outside of science, we would not be able to recognize the rationality of science.  And while it is the case that we can accept a variety of political aims while being rational, it is also the case that we can recognize the irrational pursuit of those aims, even when we do not share them.  I would go further, and say that some aims can also be recognized as irrational in themselves.  The election of Donald Trump was irrational on both grounds - it demonstrated a commitment to irrational aims, and it showed an irrational pursuit of those aims (except for voters whose sole aim was political disruption at any cost). 

  9. Neil deGrasse Tyson on science vs. denial

    Wol@10,

    You're trying to explain the irrationality of US voters in Nov 2016 as mere "opinion". Please keep in mind that the premises of such irrationale are pathological lies and/or extremely clever populous mass manipulation. I would not call the poor voters simply the others who express their "opinion", I would rather call them victims of a lie or of a clever deceit.

    Even in our First Amendment sanctioned subjective realities that are becoming fake realities, we have to mainrain a basic ethical standard. If something as bad is happening as the election of a moronic phychopath and clever manipulator to the most important world leader, we must call it what it really is: a bad thing.

    Watch for example Sam Harris interview for a good explanation why e.g. the election of current POTUS cannot be called other than "irrational".

  10. Neil deGrasse Tyson on science vs. denial

    Tom Curtis @2:

    >>...this wallowing in irrationality is not unique to the US. Brexit showed it to be alive and well in the UK. The popularity of Marine Le Pen shows it to be strong in France. The election of Clive Palmer four years ago, and Pauline Hanson in 2016 shows it has afflicted a substantial portion of the Australian population. <<

    Without going off-topic this shows a politicisation more in line with deniers' "arguments".

    At this point in time the science of climate change is to all intents and purposes settled. The way people vote may not be the way that you do, it may be irrational to some but it's not science - it's democracy.

    Don't confuse verifiable science with opinion.

  11. Neil deGrasse Tyson on science vs. denial

    Jim Eager@7,

    'nanuk' also illustrates mind numbing policy violation (all cap ordinary words), despite that policy being reminded to him/er in the past.

    nanuk@6 is arguably the worst on-topic post on this site, only marginally better than irrational/bot generated spams that are automatically deleted. I don't know the criteria mods are using for comments deleting and user rescinding but user 'nanuk' herein, certainly IMO qualifies for both.

    As the current POTUS is a blatant failure among world leaders, which crated a political situation in science and the obvious comment by Neil deGrasse Tyson in OP, user 'nanuk' is a blatant failure among SkS commenters.

    Moderator Response:

    [DB] Nanuk has recused himself from further participation in this venue, finding the burden of comporting his comments with the Comments Policy too onerous.

  12. Neil deGrasse Tyson on science vs. denial

    It really weirds me out when I hear people say that scientists don't know what they are talking about,. Without science we would not have automobiles, airplanes, radios, TV, telephones, cameras, air conditioners, electric service, computers, internet, atomic bombs, etc. All that stuff actually works, right? So, scientists seem to have a lot of stuff pretty well figured out. The scientific method works very well at establishing how things work.

    When people say they doubt scientists, they really mean, "I don't really like what the scientists are saying" which is something else entirely, and they need to be called out on that.

  13. Heartland Institute's misinformation campaign into schools

    The activity of these charlitans for the benefit of their financial masters is nothing less that child abuse.  We should make sure to publicize where their funds come from and emphasize the motivations of their funders.

  14. Rob Honeycutt at 03:58 AM on 23 April 2017
    Humans on the verge of causing Earth’s fastest climate change in 50m years

    RR... The issue of global climate change isn't that we're going to push the system outside of all historical bounds, it's that we're pushing the system faster than at any point in historical bounds. The rate of change very much is the issue and always has been.

  15. Humans on the verge of causing Earth’s fastest climate change in 50m years

    I confess that I cannot say if Dana's article is good or bad.
    My main observation is that the first chart puts together very different kind of data, which are related to different time scales. So when Dana proposes a comparison between the information of the last panel (h) with information from the previous ones, I am afraid he is pushing his hand in the wrong direction.
    In a way, instead of highlighting the uniqueness of changes that are happening right now, the article promotes the sense that anthropogenic climate change can be fitted into the natural history of the planet.
    Would do you guys think?

  16. Neil deGrasse Tyson on science vs. denial

    And along comes 'nanuk' to illustrate the mind-numbing, brain dead, fact-free wilfull ignorance tha we are up agaainst.

  17. Neil deGrasse Tyson on science vs. denial

    The problem is "Scientists" have been lying to increase their funding!  This is so obvious it is a wonder anyone accepts their word at face value!  The moment even ONE gets caught lying on data to create a specific narrative, EVERYTHING they then put out is suspect!  The true "Deniers" are the CAGW Alarmists who are now ignoring science to further their funding!

    Moderator Response:

    [JH] Blatant sloganeering stricken. 

    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.

  18. It's too hard

    I'm calling poe on andrewrussell @54, but Tom Curtis's reply was a good one anyway.

  19. Neil deGrasse Tyson on science vs. denial

    So, the March for Science is happening today, and I'ma march.  I don't know what will help to prepare the ground for public recognition of science, but if facts and logic don't, maybe marching will.  I'm ambivalent about the March, for some of the reasons offered here, and some of my own.  Then there's the near-certain futility of it.

    Near-certainty is a big enough loophole for me, though.  Let it be an atheist's act of faith.

    Moderator Response:

    [JH] The Weekly News Roundup that I just posted includes a number of articles about the March for Science — be sure to check them out.

  20. It's too hard

    andrewrussell @54, unfortunately your 70 mile wide hole, 10 miles deep only has enough volume to remove 87 mm of sea level rise, or 27 years of current sea level rise and 1/6 to 1/12th of the expected sea level rise by the end of the century.   To do that we would only need to dig an open cut 4 times deeper than the deepest mine ever built, and with an area 65 times that of the world's most extensive open cut.  That is probably not even technically possible with current mining technology, and is almost certainly an uneconomic partial solution to the problem.

    If we were to try a solution in that area, it would be far cheaper to pump water into the Aral sea to raise it to its former volume.  The lost volume of the Aral sea being about 1/3rd of that of your open cut.  Potentially raising the Dead Sea to sea level (and hence flooding the Jordon Valley), and similarly raising the level of Lake Eyre in Australia would be cheap methods with regards to engineering (though probably prohibitive with regard to economic cost for the former, and environmental cost for the later) to reduce the rate and level of sea level rise.  All such measures woudl be stop gaps, however, as the final volume of sea level rise will overwhelm anything we could do of this nature.

  21. Neil deGrasse Tyson on science vs. denial

    With climate, science collides directly into the power base of the wealthy elite that have been in control of the nation and now science is telling them they can't have all the money and all the power, they have to do something to keep the planet whole.   So they hired the "Merchants of Doubt".   This particular "tragedy" ends as badly as any imaginable, and deletes the "United" part of the national identity.   Jefferson said it would happen.  The experiment is over.  It has failed.  There is no return from where we are because the next steps do not lead to peaceful resolutions but to blood in the streets.  We reached the abyss and proudly took a giant step forward.  :-)   

    No... I do not have any optimism but I have to say that I could not wish for a better communicator or a better message.   It simply will not be seen by the people who need to see it.  

    It won't feature on Breitbart, and it won't make waves at Heartland... but even worse than that, even if they did see it, it is unlikely that they can change their minds.   They would rather die than admit such error.  They would rather die than admit that they have sold a bill of goods by the Merchants of Doubt.     

  22. andrewrussell at 17:02 PM on 22 April 2017
    It's too hard

    well i hate to brake it to you but a great majority of people running our countries are extrmily dumb. but i have a great idea and i am 100 percent positive it will work.

    in canada there are plenty of places a giant 70 mile wide hole can be dug 10 miles deep and with a mile wide manmade river we it can slowly take up the access water from the melted ice caps.
    the hole may need to be bigger im not a math matician. or a scientest but i am certain everyone else is two dumb to do anything less to fix the problem.

  23. Neil deGrasse Tyson on science vs. denial

    Great video. It's so strange that at the height of the age of science and technology, with all the triumphs, some people are losing faith in science. I would have thought the evidence for climate science, vaccines and evolution is overwhelming.

    I think the problems are a combination of the following issues:

    Obviously vested interests can make people dismiss science, an issue with climate change.

    Modern society has started to seriously question elites and conventional wisdom. This is liberal in essence, and can be healthy, but only if it's rationally based and it often isn't rationally based.

    People also aren’t equipped with the mental analytical skills to sort the wheat from the chaff. We still don’t do a great job teaching young people (or old) about logical fallacies, poor quality arguments, and so on.

    The Republican movement seems to have become more and more irrational. Maybe its a fear of science becoming too strong, and conflicting with their world views. But we all have to be prepared to modify our beliefs in light of new information. But there's just no sign of these guys seeing the light, so it's possible things are on a dismal downward spiral in America at least.

    However polls do show the majority of people accept climate science, so it’s a stubborn minority who don’t. Sometimes it just takes time to process information and accept new theories, for example it took society some significant time to accept the tobacco / disease connection.

    Also climate science has big implications, evolution collides with religion, and regarding vaccines people worry about side effects on children. These are therefore challenging debates, probably not indicative of science as a whole.

    And there’s an annoying thing we have to contend with. Many theories require complex explanations, while a short and cleverly distorted sceptical slogan or lie can take off and become embedded. To analyse all this you need time to read both sides of debates, and many people don't have much time, and respond to the simplistic sound bites typical of our times.

    You can’t convert people by totally rubbishing them. Try to reason with them, and most are receptive to this, eventually. But I have noticed it can take some time for them to come around.

  24. Neil deGrasse Tyson on science vs. denial

    Mal Adapted @1, the 2016 US Presidential election has revealed a deep seated irrationality in the US electorate that extends well beyond the rejection of science.  Like you, this has left me profoundly pessimistic about the prospects of our civilization.  Much as we like to say, it could only happen in the USA, this wallowing in irrationality is not unique to the US.  Brexit showed it to be alive and well in the UK.  The popularity of Marine Le Pen shows it to be strong in France.  The election of Clive Palmer four years ago, and Pauline Hanson in 2016 shows it has afflicted a substantial portion of the Australian population.  

    If this commitment to irrationality continues much longer, the Romano-germanic civilization that has dominated Europe since 1100 AD, and the world since about 1600 AD will not last much longer.  That, of itself, will be tragic only to nations and people steped in that culture - but given the present threats of Anthropogenic Global Warming, habitat destruction, over-fishing and, in the background, nuclear war, the fall of the Romano-Germanic civilization may be the prelude to the fall of all civilization on this planet.  These are all threats that can be dealt with, seperately and conjointly, but they require rational policy to do so. 

  25. Neil deGrasse Tyson on science vs. denial

    There is no daylight between my own and Dr. Tyson's positions on the privileged authority of science, or the importance of basic science literacy (or better, meta-literacy) to democracy. 

    That said, I'm pessimistic that his manifest certainty of science's epistemic authority will be persuasive to non-scientists in the PoMo era.  The 2016 elections were a big shock to me, in my 7th decade. Telling people with little early exposure to science how ridiculous it is to deny AGW may be gratifying (personal experience), when you're a random guy on the Internet .  It evidently hasn't done much to enhance science's credibility with the public, though, even coming from the likes of NDT.

    IMHO there clearly is more to be done to prepare the ground before telling them they're fools for denying it.  Damfino what, though.  I'm hoping for a sort of heroic scientist-educator-politician; oxymoronic, I ruefully admit.  Depressive realism, or mood-congruent thinking?  You be the judge.

  26. Heartland Institute's misinformation campaign into schools

    I'm surprised there is no link to the offending book(let). If for nothing else, there is the idea set out in the audio (Ep8 in theOP) that the book(let) is so wrong in its message that it presents an educational opportunity. So a link is surely needed for all those educational institutes who the deluded denialists Heartland Institute have yet to reach.


    I was also a bit shocked by the reference in the audio to Bob Carter's death. It is true that the booke(let) is the work (I should simply call it "lies" rather than "work") of three fake experts and such fake experts are indeed not such a numerous species. But Carter's name on the book(let) is not a case of postumous attribution of authorship. The book(let) was published a month or so prior to Bob Carter's death.

    Mind, the book(let) tells us it is based on a chapter from a far bigger work but that bigger work has yet to see the light of day. From what we are told, the bigger work would be 1,000 pages. (It is described as the third volume of a marathon 3-volume writing exercise which will apparently total 3,000 pages. The first two volumes comprise 933 pages & 1,062 pages.) Presumably, this Volume 3 of their magnus opus will be no more truthful than the preceeding pair. (I assume the second volume is nought but a pack of lies for the first certainly is. I checked a random section of their first volume  (Section 2.1: Forcings & Feedbacks - Carbon Dioxide, pp151-165.) and found fifty-seven fundamental errors.)

     

    The audio does discuss addressing the bare-faced lies within the book(let) ("...refute all the physical science claims they are making which are wrong...") but argues that it is more important to counter the bogus claim that "the 'scientific consensus' on the causes and consequences of climate change is without merit." While I would agree, pointing out the eye-watering stupidity of the bogus experts from NIPCC & Heartland can surely assist in showing how bogus is their primary claim.

    And with that in mind, when I randomly picked a chapter from the book(let) and then examined the primary evidence presented to support their first claim in that chapter I found these liars are actually 'hiding the incline' in a manner many time more significantly than the famous 'hide the decline' which they made such a fuss over. Their 'hide the incline' is illustrated by this graphic (usually two clicks to 'download your attachment').

  27. Heartland Institute's misinformation campaign into schools

    Bast has done some reprehensible things in his long career, but mispronouncing 'Oregon' (25:29) is probably the least forgiveable.  I'm 97% sure, or 0.3%, depending on who is counting.

    Outside Heartland Package: "Why do Scientists disagree about Global Warming?"

    Inside Heartland Package: "Send in this card with your name and address and you, too, can be a 'Scientist'!  We'll ship your diploma out immediately!"

  28. Increasing CO2 has little to no effect

    DrBill @309, radiation models are not climate models.  They determine the transfer of radiant energy within the atmosphere given a set of conditions which include well mixed greenhouse gases present, water vapour present, clouds present, and atmospheric density and temperature profiles.  They were first developed for the US Airforce as part of its effort to develop infrared guided missiles (Sidewinders), and were later used for the development of FLIR systems, for interpreting microwave radiation from the atmosphere as temperature, and of course, for determining IR radiation from the atmosphere.  As such, they can determine the change in Outgoing Infrared Radiation given a change in atmospheric profile, where such changes at the tropopause are also the change in atmospheric forcing.

    In 1970, LBL radiation models could produce results as accurate as this if fed detailed atmospheric profile data gathered by a weather balloon:

    By 2008 they could produce results with accuracies like this with more approximate profile information:

    Further, for determining radiative forcing, the models are generally set with a temperature profile determined by radiative/convective equilibrium in the troposphere (ie, one that follows the adiabatic lapse rate), and with a radiative equilibrium above the tropopause, and therefore complies with the requirements of the laws of thermodynamics (including that for Gibbs free energy).

    Of course, radiative models only determine forcing, and not the temperature response to forcing within the troposphere.  (They can be used to calculate the initial temperature responce in the stratosphere and above were radiative equilibrium obtains.)

    Global Circulation Models, which determine temperature responce as well as radiative response, also include approximations to the laws of thermodynamics governing movement of gases under gravity.  (Approximations only given the limits of cell size required to make the models able to operate on modern super computers.)

    Moderator Response:

    [JH] Spencer Wart has detailed the history of General Circulation Models here

  29. Heartland Institute's misinformation campaign into schools

    The so called Heartland package on climate change is not so much a sceptical viewpoint, as a collection of lies, deceptions and plain nonsense. As such I would have thought it doesn't meet the threshold of quality and reliability, for material to be taught in schools.

    However students will be aware of some disagreement with climate change theory, and its unwise to pretend this doesn't happen. If sceptical viewpoints must be mentioned in schools, at least keep them to the saner ones, and put them in context, and discuss their weaknesses (and there are many huge weaknesses).

    It's also time we taught students tools to see through poor quality ideas, logical fallacies such as red herring arguments, cherrypicking information, non sequiters, etc,etc. There is so much fake news, and flakey theories, or conspiracy theories, and it's sadly not going to go away, and is the price we pay for an open society and freedom of speech. Students need to know how to evaluate this material rigorously.

  30. SkS Analogy 1 - Speed Kills

    Because the original plot of the annual rate of increase of CO2 showed too much annual variability, I replaced the original figure with a 10-year average of annual CO2 flucuations. For reference, the original figure is shown here.

    10-year average of annual rate of CO2 increase.

  31. SkS Analogy 1 - Speed Kills

    Point taken William, and my mistake. I will be more careful in the future.

  32. SkS Analogy 1 - Speed Kills

    Perhaps it is a minor niggle but I wish we would agree on terminology and then continue to use it.  As I understand it we are in an ice age which started some 2.5m years ago.  During that period, we have had about 30 glacials or if you like glacial periods and about 30 interglacials.  We are at present in the Holocene interglacial and the previous one about 125,000 years ago was the Eemian interglacial (or interglacial period).  In the first half or so of this ice age, the period was about 41,000 years but more recently the period has been around 100,000 years.  It doesn't help educating the non scientific community if we use sloppy terminology.  I don't care if we decide to call glacial periods ice ages but then we need another term for the recent 2.5m years. 

  33. SkS Analogy 1 - Speed Kills

    I am not an expert on the CO2 dataset, but my expectation is that like temperature, the absolute values jump around a lot from year to year. That is why the best way to view the data is with a fitted curve. For the analogy I calculated the rate for each year. Converting the data into a 10-yr. average of the CO2 rate of increase produces the following plot, which loses the big variations in data, but preserves the overall trend.

    10-yr CO2 avg

  34. SkS Analogy 1 - Speed Kills

    The BBC also reported on the rate back in 2006

    "The "scary thing", he added, was the rate of change now occurring in CO2 concentrations. In the core, the fastest increase seen was of the order of 30 parts per million (ppm) by volume over a period of roughly 1,000 years."... "The last 30 ppm of increase has occurred in just 17 years. We really are in the situation where we don't have an analogue in our records,"

    http://news.bbc.co.uk/2/hi/science/nature/5314592.stm

  35. Increasing CO2 has little to no effect

    The free energy change of a process is the sum of energy and entropy*temp, and is generally regarded as happening spontaneously when the sum is <0. A version of free energy is that of Helmholtz, whose summation is ΔF (or ΔA) = ΔE -TΔS, but another is the Gibbs ΔG=ΔH-TΔS. The difference between the two expressions is that ΔE and ΔH are not the same thing: ΔE, as I've been used to thinking of it, is now named ΔU, while ΔH = ΔU + Δ(pV).  In short, Gibbs Energy includes PV work, while Helmholtz does not when evaluating the possibility of a spontaneous process.  A view of this, which I hold, is that the ΔE portion emphasizes the radiative changes, while the ΔH portion includes pV work.

    Since the atmosphere not only radiates energy in trying to come to equilibrium, but also does substantial pV work, I believe a model that seems to rely on radiative transfers is not sufficient to explain the climate.

    In support of this, I refer the reader to the 1962 and 1976 editions of The U.S. Standard Atmosphere.  Google links lead to pdf's and I don't know if anyone wants to wade through dozens of derivations and perhaps 60 pages of notes and explanations, so I won't burden this post with the links themselves, unless someone wants them.  In summary, the NASA, NOAA, and a host of other sponsors and contributors determine a model of the atmosphere based on gravity and Cp ((∂H/∂T)p [see @301], and regard CO2, methane and NOx as "trace gases" with no significant impact on temperature.  Similarly, the lapse rate -g/Cp suggests the derivation from Gibbs.

    The dichotomy is strong enough to get out the old slide rule, imo, and attempt to recognize something fundamental like Cp in the forcing equation.  I have not so far.

  36. SkS Analogy 1 - Speed Kills

    This is a very useful rebuttal to "The climate is always changing." argument. 

     

    For or those who don't care about nature, it would be helpful if there were a mention that agriculture is also affected.

     

    is there an explanation for the three very high points?

  37. SkS Analogy 1 - Speed Kills

    The post-1950's data is a simple linear fit in Excel. Nothing fancy. Although one can eaily make the case for CO2 rising faster than a linear trend (as pointed out in the responses), in this analogy the point was to simply introduce the idea of just how much faster we are moving than a "base rate" defined by deglaciation cycles.

  38. Increasing CO2 has little to no effect

    Just a quick thanks to Tom CurtiS, JH and RH.  FWIW, I tried several ways to make the page show up and not until this evening did I try to quit and relog in, and that seemed to work.  I agree with chriskoz about courtesy and thank Tom for recognizing a typo.  If JH/RH don't mind, I wouldn't mind seeing my 302,3,4 deleted; 301 had all I had in mind to ask, as it had reference to the partial derivatives that result in Cp.  It's late here, for me, and I'll post a new submission tomorrow.

  39. Increasing CO2 has little to no effect

    DrBill @301, the formula for radiative forcing was not directly derived from fundamental physics.  Rather, the change in Outgoing Long Wave Radiation at the tropopause, as corrected for radiation from the stratosphere after a stratospheric adjustment (which is technically what the formula determines), was calculated across a wide range of representative conditions for the Earth using a variety of radiation models, for different CO2 concentrations.  Ideally, the conditions include calculations for each cell in a 2.5o x 2.5o grid (or equivalent) on an hourly basis, with a representative distribution and type of cloud cover, although a very close approximationg can be made using a restricted number of latituded bands and seasonal conditions.  The results are then have a curve fitted to it, which provides the formula.  The same thing can be done with less accuracy with Global Circulation Models (ie, climate models).  

    The basic result was first stated in the IPCC FAR 1990.  That the CO2 temperature response (and hence forcing) has followed basically a logarithmic function was determined in 1896 by Arrhenius from empirical data.  The current version of the formula (which uses a different constant) was determined by Myhre et al (1998).   They showed this graph:

     

    The formula breaks down at very low and very high CO2 concentrations.

  40. Digby Scorgie at 10:59 AM on 20 April 2017
    Humans on the verge of causing Earth’s fastest climate change in 50m years

    Tom Curtis @9

    When the "level of economic harm and natural disasters" becomes sufficiently catastrophic, I can't see anything less than a collapsing global civilization, with huge numbers of people dying of starvation and strife (Syria many times over) and economic activity plummeting as a consequence.  Local civilizations will still survive but far less fossil fuel will perforce be burnt.  Anyway, that's my gut-feeling — but then I'm a cynical old man.

  41. Antarctica is gaining ice

    Should this discussion be updated to account for the recent record lows in Antarctica's sea ice extent?

    jlsoaz: Did you look at the National Snow & Ice Data Center's website, nsidc.org?

  42. SkS Analogy 1 - Speed Kills

    The analogy does make some good points, & clearly. Does anyone besides me worry, though, about using the period 1851-1950 as the comparator? For that period to be meaningful, it would have needed to last as long as we expect our current warming rate to last (probably many centuries, under a business-as-usual scenario), & we would need to have observed the warming's impacts on food supplies, sea level rise, weather & so on.


    Since 1851-1950 was not that long, maybe a more meaningful comparator period would be the last previous period of warming of >1,000 years (ignoring any periods with other factors present that would grossly exacerbate extinctions & so on, such as asteroid hits).

  43. Increasing CO2 has little to no effect

    chriskoz @305 while I agree that correct spellings of names is a matter of courtesy, DrBill spelled my name correctly in three posts prior to that @304, so it is reasonable to assume that that mispelling was entirely inadvertent.  Further, "most accomplished" is a compliment that suggests significant acheivement in a scientific field, whereas I lack even a BSc.  I take that as a compliment to my depth of understanding of the topic, for which thankyou.  However, while I think is deserved, that depth is limited, especially relative to anybody with a PhD in atmospheric physics.

  44. Science of Climate Change online class starting next week on Coursera

    Hello All,

    No the moderator is wrong. I have learned all I can learn, you folks have helped me, and I am on my way.

    Cheers.

    Curiousd

    Moderator Response:

    [JH] May the Force be with you. :)

  45. Corals are resilient to bleaching

    A note that even after another hot summer of coral bleaching, this time without an El Niño, Jim Steele doesn't seem to have learned much. He's written an article on the web entitled "Falling Sea Level: The Critical Factor in 2016 Great Barrier Reef Bleaching!" attacking Hughes et al (2017). Global warming and recurrent mass bleaching of corals. Steele's article has been referred to by James Delingpole and others, presumably because it tries to blame anything other than sea temperatures for coral mortality despite their evident close relationship.

    The article about coral mortality in Sulawesi he references would not explain bleaching and its authors support the overall picture of thermally-induced bleaching and mortality. One of his suggestions is that Hughes's demonstration of mass mortality of the northern GBR was based entirely on aerial surveys. That is false, as can be seen in reports for example in SciAm or New Scientist. Although this has been pointed out to him, Steele has as of 19 April yet to correct these errors.

  46. Increasing CO2 has little to no effect

    DrBill@304,

    Please show a bit more respect to Mr Curtis by taking care to spell his name correctly. The fact that Mr Curtis in one of the most accomplished commenters on this site calls for even more care.

    Then people will show more respect to you and your comments, reciprocally.

  47. SkS Analogy 1 - Speed Kills

    Typo in my post@2.

    "dppm/dy" should read "dppm/dt". Sorry.

  48. SkS Analogy 1 - Speed Kills

    If I read the plot correctly, the linear trend since 1950 does not look to fit the data. The data rises faster than the line in the figure. And the data in more accurate than pre-1950 part (I'm assuming data comes from MaunaLoa and rapid accumulation ice cores respectively).

    So, since the y-axis is already a first derivative (dppm/dy), while the x-axis is linear, the actual CO2 trend looks faster than quadratic since 1950. This is the first time I've realised it. I don't need to explain to people on this site what ultra-quadratic trend means in context of "Elevator Statement" above: more than freefall, more than gt2/2. Those politicians who still have such basic understanding of maths & kinetics (sadly none associated with GOP in US) should be given this post to read.

  49. Yes, we can do 'sound' climate science even though it's projecting the future

    @ubrew12: Good points. The third point is also a giant misapprehension even if you grant the premise. I happen to agree with what Spencer says about the the Earth, but this does not give us a free pass — his conclusion is a total non sequitor. You cannot cross the street without looking and say nothing happens without God's will, so there's no danger. Not looking is part of what is happening; nothing anybody believes about the Earth or Mother Nature can suspend cause and effect. Balance is always restored. What we do and don't do matters a great deal. The Israelites are told to plant trees, to allow the land rest (fallow), etc., if they want to keep the land as their inheritance. Nowhere does it state that it doesn't matter what you do. Quite the opposite. There is no religion that states that you endanger your life and soul if you kill a fellow human being, but pouring infinite amounts of CO² into the atmosphere has no consequences, the indulgences have already been provided in advance at no cost.

  50. Science of Climate Change online class starting next week on Coursera

    curiousd @39.

    So, concerning the graph you introduced @25, it is incorrect to say that "This image has to do with the last correction,"Correction Three" to MILA." In truth it has no bearing in the development of your "Correction Number Three" , the graph being the result of your use of SpectralCalc. As we continue to have great difficulty getting to grips with your use of MILA, adding the output of a different model into the discussion is a step too far.

    Concerning your "Correction Number Three", I repeat my comment @33; it is only duplicating your correction resulting from the limited spectrum under analysis within MILA ( your "Correction Number One"). And I still see no reason for your "Correction Number Two" because there is no reason to believe that the MILA calculator is not already adjusting using a "diffusivity approximation".

    And may I be so bold as to suggest an alternative to this torturous discourse we engage in here. You could approach UoC concerning their MILA asking for their understanding of the different approximations their model encompasses and their relative impact on the output.

    Moderator Response:

    [JH] As long as you and/or Tom Curtis respond to his posts, curiousd will likely keep pursuing this matter on this website.

Prev  396  397  398  399  400  401  402  403  404  405  406  407  408  409  410  411  Next



The Consensus Project Website

THE ESCALATOR

(free to republish)


© Copyright 2024 John Cook
Home | Translations | About Us | Privacy | Contact Us