Thanks to Thomas Palm for pointing out the link, over on sci.env.
2020 update: see-also 2007's The Use of Damon and Laut.
TL also found this junk from Paul so I have another one to add to the myths: that heat pollution is a significant source of warming (this one isn't intrinsically silly, though the post by Paul certainly is: people did use to worry about it, till they realised it was small compared to CO2 effects).
1. Its all models Well obviously the measurements of the current temperature rise aren't (except the ones from the satellites, which do have to be passed through a model, ha ha, so its ironic that the same people who will argue "its all models" tend to prefer the satellite record...), nor are the observed rise in GHG's. But projections of future change inevitably come through models. But these models are themselves constrained by observations (match to the past century) and theory (basic radiative transfer; feedbacks; etc).
Consensus science is not science. Incredibly, some people are capable of arguing something along the lines of:
- Science is not done by consensus
- There is a consensus on X
- Therefore, X is wrong.
This is obviously silly. It is true that science isn't done by consensus - but so what: no one is saying it is. But when you're thinking of science advice to policy making, you ought to follow the consensus/majority view.
I've sort-of done this before.
3. All the scientists say the same thing because otherwise they will lose their jobs. This one fails to explain the existence of skeptics like Lomborg, Lindzen, Spencer or Svensmark. And it fails completely to understand the nature of scientific society. It isn't some kind of Sekret Kabal. Its an open process: if there are holes in a theory, you can make a name for yourself by pointing this out. I would say that consensus-busting papers stand more chance of being published (on an assumption of equal technical merit) than those supporting it: purely because of the requirement for novelty which journals impose.
4. Water vapour is the dominant greenhouse gas. Well no, it isn't (since I blogged this myself, I'm embarassed to have forgotten it). Its the submissive GHG :-)
5. CO2 saturates within 1m/10m. This one is fairly technical so not very popular as a myth, because it requires a bit to even understand it. The idea is that increasing CO2 won't matter, because the CO2 absorption regions are saturated anyway. Now this isn't one of my strong points (Josh?) but as I understand it this is why the radiative response to CO2 is linear (v low CO2 levels) to sqrt (moderate) and log (current levels).
6. There are not enough fossil fuels available to increase CO2 levels. This one is fairly rare and I'm not sure anyone really believes it. Oil might run out but I don't think there is any shortage of coal, tar sands and misc gunk to get us to at least four times pre-industrial CO2. I find it hard to believe that the future emissions scenario constructers failed to consider this point.
7. Its all the sun. Solar forcing has probably increased over the last century, but as far as can be told its small compared to GHG's. And it has (I think) decreased recently (last few decades)). The solar stuff tends to rely on correlations, whose significances are hard to assess - because the std statistical analyses rely on you doing the assessment once, not on keeping searching for things to correlate till you get a result. Mention here for Paul Farrars work on aliasing of ENSO onto the cloud signal, and the changing-their-minds stuff about polar or mid-latitude clouds. And the bit about the dodgy numbers at the ends of the record (Laut?). Sorry: life is hell without a proper connection...
8. Its all hype to get funding. This one has a grain of truth to it. Agencies do tend to look favourably on proposals which are relevant to the real world. Amusingly, this is probably why a number of solar type folk have got interested in GW and are pushing the solar-GW connection: its good for funding. Which shows up the converse: of the skeptics, plenty have tenure; plenty of tenured people aren't skeptics. But if you want large funds and high salaries... you don't go into science to start with, or stay there.
9. CO2 lags temperature in cores. In facts its pretty hard to tell whether is does or not, because the CO2 comes from the air trapped in the bubbles but the temperature signal comes from the ice itself. And this leaves an uncertainty as to the age of the CO2 relative to the ice, because the pores in the ice only close off slowly - leaving uncertainties up to about 800 y in high cold cores like Vostok. And when you're plotting picture to play with the data yourself, its hard to know what adjustments have been made, so be careful. However, having said that, I think that what indications there are do tend to indicate temperature leading CO2. But: this is not terribly relevant. Trying to explain the last 800 kyr of ice ages, there is a puzzle as to the size of the forcing, which needs an amplifier to produce the size of response. CO2 feedback is one candidate. In which case, you would expect T to lead CO2. But in the case of current climate change, we know full well that the forcing is CO2, not temperature.
10. Fred Singer has anything useful to say about global warming. The traditional number 10: not one that many people believe. Did you know that of those listed on the board of advisers to SEPP, three are dead? Play a fun game: see if you can guess which they are (no cheating by looking at the wiki page).
1. In the 70's, everyone was predicting an ice age: fairly common in disrespectable circles but comprehensively refuted by the excellent if over-long and byzantine http://www.wmconnolley.org.uk/sci/iceage/, and more comprehensibly by www.realclimate.org/index.php?p=94. Yes I know I mentioned this only recently (and JF picked up on it).
2. Its all the Urban Heat Island: no it isn't: see The Surface Temperature Record and the Urban Heat Island. In fact, recent evidence suggests less UHI that reported by the IPCC TAR.
3. The surface may be warming but satellites show the atmosphere is cooling: not true: depending on how you built the satellite record, it shows a warming of between 0.08 oC/decade and 0.26 oC/decade, from 1979 to 2004 (ish). See http://en.wikipedia.org/wiki/Satellite_temperature_measurements for the details. There is a kernel of truth to the myth: once upon a time (last in 1996) the satellite record did show cooling, but never as large as the warming it now shows.
4. The hockey stick is broken and therefore the current warming is not unusual: the MBH98 "hockey stick" graph was groundbreaking in its day, but there are now several other reconstructions: the best pic I know of is at http://en.wikipedia.org/wiki/Image:1000_Year_Temperature_Comparison.png. But... its by no means clear at the moment which (if any is correct); and all show the current temperatures and rate of rise to be unusual. Its also true that the hockey stick is not quite as important as the septics often like to claim: What If … the “Hockey Stick” Were Wrong? at RealClimate is interesting.
5. The current CO2 rise is natural, not man-made: this one is totally absurd. To believe this, you have to believe that CO2 and other GHG's were stable at pre-industrial concentrations for thousands of years, then suddenly, just as humans started emitting them, some natural process started emitting them, while at the same time removing from the atmosphere an equivalent quantity of the man-made GHGs (yes I know about the resident fraction...). This is the obvious argument; more complex ones from isotopic measurements can be made, e.g. at How do we know that recent CO2 increases are due to human activities? (update). BTW, notice I've used "man-made": I could have said "anthropogenic" but this is just man-made said in greek.
6. Climate is always changing. True, but so what? We care about the magnitude and speed of current and likely future changes; "climate is always changing at current rates" is definitely false; its all about timescales. See Why do people say... Climate change 'is the norm'?
7. Global warming will cause cooling! Or, the "Day after tomorrow" effect; or Thermohaline shutdown: people love this one because it appears paradoxical. The basic idea (twisted so badly by TDAT (as I understand it; I never watched the stupid movie) that its unrecognisable) is that GW will, by freshening the waters of the north atlantic, lead to a shutdown of the thermohaline circulation, a shutdown of the gulf stream, and therefore massive cooling over northern Europe. THC shutdowns have probably occurred in the past, as a result of freshwater discharges, but only while there are large ice sheets over north america. The Gulf Stream is not the same thing as the THC. And as far as can be told, the probability of a THC shutdown is not high: in fact, it doesn't happen "by itself" in coupled models runs, you have to force it to happen; what you get is instead a slight slowdown and although there is a cooling tendency from the slowdown, the overall effect is warming, even over northern europe. The TAR, section 126.96.36.199 Thermohaline circulation changes is good, as always.
8. The ozone hole and climate change. Not really a myth, just a confusion: the connections between ozone hole (or, better, ozone depletion) and GW is thin. They are: (a) ozone holes require very cold conditions; GW will warm the troposphere but (possibly confusingly) cool the stratosphere where the ozone is; hence, there will be a tendency for GW to cause more depletion. OTOH CFC levels are expected to decline. (b) ozone depletion represents a radiative forcing of the climate system, overall a net negative forcing: ie, it tends to cool the troposphere and surface (c) both GW and OD tend to cool the stratosphere; this cooling is observed but not as useful as it might be as a fingerprint of GW, because of the ozone changes.
9. The greenhouse effect keeps greenhouses warm: not so.
10. Nils-Axel Mörner has something useful to say about sea level rise: fortunately, very few people believe this one... perhaps this is why...
11. Uncertainty. Once the septics have run through about every other excuse they are down to pressing the virtues of uncertainty: that because we don't know in enough detail the effects and size of GW, we should do nothing yet. Of course they don't really mean "do nothing"; they mean "do nothing to reduce our emissions of GHG's". This seems to be the current position of the Bush govt: obliged to admit the reality of the current temperature rises, and even describing it as "sharply rising" (thus stomping on the std.septics, but they keep quiet about that), the POTUS continues... We do not know how much our climate could, or will change in the future. We do not know how fast change will occur, or even how some of our actions could impact it.. Well, this isn't really right: we do in fact know that emitting CO2 will warm the climate. But anyway, (as Michael Tobis has argued on sci.env better than I can, sadly I can't find it right now) uncertainty should make you feel unsafe, not be some sort of we-don't-know-its-ok cocoon.
Well, thats enough myths for now. If I've forgotten some, I hope you'll let me know.
1 301 28.05% bee
2 103 9.60% head lice
3 74 6.90% bees
4 64 5.96% potty
5 30 2.80% old shed
6 29 2.70% legoland
7 20 1.86% swarm of bees
8 13 1.21% still life
9 13 1.21% swarm
10 11 1.03% watch tv
I don't understand "still life" or "watch tv" (we don't have one!).
Oh... and did I mention that my wife got through to the second round of the advanced III category EPTA piano competition, playing Rachmaninov Etudes Tableaux in F minor, G minor and C major? Well she did.
I did have a letter printed in the New Scientist: in response to some tedious skeptic (here, but you need a subscription to read the interesting bits), I said:
Kevin Mayfield manages to make two errors in one short letter (5 March, p 32). The second (confusing weather with climate) is commonplace. The first (believing that 30 years ago an ice age was predicted) is less common but just as wrong. See: www.realclimate.org/index.php?p=94 for a readable explanation or www.wmconnolley.org.uk/sci/iceage/ for more detail.
but this is hardly a new thing.
I posted that I was doing a talk at Cafe Scientifique on Wednesday 16th, and now I've done it, and the photo is the proof: me (left); Howard Griffiths (centre) and Pete Convey (right). Its at the question time, afterwards.
So... how did it go, I hear you ask? Quite well, I reply. A decent audience (70+), I presented my stuff well (aided by having 20 mins, about twice as long as I was originally expecting) and so did the others with theirs. You can if you wish read my ppt presentation (or my sxi presentation, if you prefer :-) at http://www.wmconnolley.org.uk/sci/gw/ but I fear you may find it unilluminating without my voiceover.
I was midly disappointed by the questions afterwards. Where have all the skeptics gone, for one thing. And perhaps a lack of deep knowledge for another (obviously you wouldn't expdct DK from everyone, but I would have hoped for a few). Perhaps everyone was quite convinced... Also the bios (somewhat to my surprise) were able to find plenty of examples of cl ch showing up in the biology, but nothing you could call bad, in and of itself.
And afterwards to the Castle for some Oyster Stout with friends.
To celebrate, here is a picture of a daffodil with the sun behind it that I took on the rec today.
There was a good sunset too, with hints of iridescence in the upper clouds.
Meanwhile, says the news, Brent Crude is now over $56 per barrrel, due to surging demand, especially from China :-(
[Update 2005/03/17: I discover that Het is HET: Harvey Elmer Taylor. Sorry about that. It makes no real difference, but it does alter my mental picture of him: I thought Het sounded Dutch, and I portrayed him as a somewhat dour Dutch chap, perhaps a bit like a bargee with a pipe and a cap. Now I know he is a Harvey, well, I'm not sure what a Harvey looks like :-)]
ie, what I did in february.
[Updated to include picture: someones been having fun with stoatoshop!]
But wiki as a soap opera can provide you with hours of entertainment if you want, with the added thrill that at any time you feel like, you can participate. Soap opera is all about conflict of course, so a good place to start is Requests for arbitration. This is, as the page says, the end of the dispute resolution process, when all else has failed. One that I have an passing interest in is the case of 172, who I only know from his unwise protect of the GW page. Elsewhere he may be quite sensible, but he has certainly riled some people and it looks like his case will be accepted - ie considered for arbitration. See also the 3 reverts rule enforcement page for the full bizarre history - he ended up having a blocking war with other admins, only ended when Ed "capricious" Poor stepped in and de-sysop'ed them all. Ed gets away with lovable-but-stupid things like this because it all works out well in the end (so perhaps they aren't stupid...). I got an hours ban for sarcasm from him just recently (and M says I should have got another for this). Hmpf. The other case I've been interested in (indeed I started the RFA) is RFA:JonGwynne who (thank goodness) now appears to have gone away entirely, presumably since the case went so badly against him.
Other places to look for exciting conflict on wiki are Requests for comment where people can list pages or people they think are bad, biased or in some way in need of comment from the wider community. Browsing that recently I picked Wave-particle_duality and made some notable improvements... I think... well check the history. Why don't you pick one on the list and go and help it out?
Another way to follow strands is to pick a page - GW, or any page - and click on the "history" tag at the top, to find the list of contributors, then click on one of the users who has contributed to see their user page, then click on "user contributions" (probably in the "toolbox" in the sidebar to the left, though this can vary if you have a different "skin" selected) to see what else they have been up to. Miriam does this for the GW related pages to see if the people I am in conflict with to see if they have genuine and productive edit histories elsewhere.
And if all else fails, you can look at the Recent changes list.
The interesting question is, *why* does the stratosphere cool? From asking colleagues, its quite clear that very few people have thought about this, and of those few who do think about it few get the right answer. Indeed, I'm not absolutely sure that what I've written below *is* the right answer, but I think it is. For a long (and possibly doomed) attempt to explain it, see this at RealClimate.
[Clarification: 2005/03/05: I fear I may not have been quite as explicit as I might have been: this post is about why the stratosphere cools if all you do is change the GHG's, e.g. CO2. It is not about what happens if you decrease the ozone - that, trivially, cools the stratosphere. Consequently, I am not talking about the observed decrease in temperature in the strat - which is caused by a mixture of ozone depletion and GHG increase - but about what *would* happen in a though experiment if GHG's are increased but ozone is held fixed.]
Anyway: my explanation (thanks HKR) is:
in a uniformly grey non-convecting atmosphere (ie, if the atmosphere were equally transparent at all wavelengths, and uniformly through its depth) heated from below (ie, solar radiation warming the surface; assuming of course that we've relaxed the grey assumption to let the solar through), then increasing the greenhouse gases (GHG's) *doesn't* lead to a cooling at the top: instead, the whole atmosphere warms, though not uniformly. You can see some calcs and pictures and code here;
of course, the real atmos does convect; isn't totally transparent to solar; etc; but the real difference is:
the reason that the real atmosphere has a stratosphere is because of ozone absorbing UV, thereby warming that portion of the upper atmosphere;
hence the stratosphere is considerably warmer than it would be under just longwave (LW, or IR) forcing; and CO2 is only effective in LW frequencies;
hence, increasing CO2 *increases* the stratospheres ability to radiate in the LW, but doesn't substantially increase its ability to gain heat, because most of that comes from the SW;
hence it cools.
In the troposphere (ignoring convection etc etc; the real atmos is complex...) increasing CO2 increases both the ability to gain and lose heat, and this first-order argument doesn't tell you what will happen; as it turns out, it warms.
Note: of course the fact that many people couldn't explain this makes no difference at all to the fact that climate models produce the correct answer: they just integrate the equations, and don't care about *why* things happen.
[Update in response to comment: the troposhere is the lowest bit of the atmosphere - up to about 8km. Temperature generally decreases with height at about 7 oC/km. The stratosphere comes next, temperatures *increase* with height (the temp min defines the interface, called the tropopause) until the mid-strat, then declines again to - I think - the stratopause. See IPCC glossary for more.
CO2 is only radiatively active in the LW - ie the infrared portion of the spectrum. Its just about transparent to visible (SW) light]
Someone who shall remain anonymous said my posts were too long. So I'll stop now :-)