2005-03-24

Myths of the Near Future

This post is about myths of global warming, but calling it that would be dull; it was going to be called Fables of the deconstruction but MotNF seemed better and perhaps more obscure. Partly, its a feeble attempt to gain wordshare by recycling some old posts, but there is some new stuff. To save time and space I haven't trawled for the evidence of people that believe these myths.

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 9.3.4.3 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.

10 comments:

Anonymous said...

Thanks for all your work William. Some myths I keep running into:

It's all based on computer models.

It's "consensus sciense" which isn't really science.

No scintists can disagree with the prevailing paradime, if they do they will lose their jobs, or funding, or will never be able to publish etc.

Jim

Anonymous said...

I know I bang on about this, but it's always worth repeating.

"Common sense" is supposed to be applied to all these issues, right? We could always be generous and say this is a synonym for "scepticism" or "Occam's Razor", both of which I am rather fond of.

So let's apply some common sense to the theory that all these scientists are applying a prevailing paradigm, and that any brave dissenters are being punished by mockery and exclusion.

Now these venal scientists, so busy defending themselves, their jobs and their empires, are hardly likely to bite the hand that feeds them.

So why on earth have they formed a vast unified community to say something that absolutely guarantees that the government and corporate interests that funds them, hires them and honours will be completely and totally PISSED OFF?

As our Right wing friends are prone to say, archly -

just asking..

- barista

Anonymous said...

Very nice post.

A couple more common skeptic myths I've come across are:

1) The present warming is all due to the Sun, which is often mentioned in connection to the Svensmark effect with cosmic rays and clouds.

2) Most of the natural greenhouse effect is due to water vapour- which is true- but then they quote some ridiculously large figure like 95% for the percentage. They also take it to mean that CO2 isn't a significant GHG, and therefore we shouldn't be worried if it increases.

I've also encountered the argument that climate scientists hype up AGW just to get more funding from Governments. Funnily enough, the same people often have no problem believing scientists in other areas...

- Brian

Anonymous said...

Oh...just thought of another one:

3) CO2 concentrations have been found to lag temperature in the ice cores, and therefore CO2 can't cause any warming.

The answer to this one is to actually read the papers that found this (and explain why this argument is over-simplistic) rather than dodgy websites.

I think it's very useful to have these arguments collected all together in one place, since if one hears them repeated for the millionth time one can just point to this page...

- Brian

William M. Connolley said...

Thanks for all the myths I'd forgotten. One of them - WV - I've even blogged on earlier - oops. There are enough for another post, tonight or tomorrow!

Keep them rolling in...

Anonymous said...

Great Idea Dr. C. Having all these myths in one place will be a real bonus!! Here are a couple more myth.

The existing CO2 absorbs all IR withing 1 meter (or 10 meters, or 100 meters, whichever skeptic you happen to be listening to) so it doesn't matter if we add more.

Over on RealClimate Eli did a good job of shooting this one down.

Another is:

Water produces 99% of the greenhouse effect so CO2 doesn't really matter.

Thanks for this idea.

Regards,
John

Anonymous said...

re: 10
Sorry William, this is a plain ad Hominem attack, and not adressing the issue of peer reviewed sea level rise publications..

Might work in politics, doesn't work in science...

Anonymous said...

Another myth
1. There isn't enough fossil fuels to increase CO2 levels as projected by IPCC.
(This one is generally derived by only considering oil and ignoring coal)

Here are some suggestion for answers to a couple of the myths in the comments:
"No scintists can disagree with the prevailing paradime, if they do they will lose their jobs, or funding, or will never be able to publish etc."

Witness how Lomborg, a completely unknown scientist with no publications in any environmental science became an overnight world celebrity by publishing a book attacking, among other things, global warming, and it wasn't even a good book. In a similar vein being critical doesn't seems to have hurt the careers of Lindzen, Spencer or Christy.

For the "Svensmark effect" I recomment this page:
http://stephenschneider.stanford.edu/Publications/PDF_Papers/DamonLaut2004.pdf

Anonymous said...

I hope you'll soon add the myths to your list that other posters have mentioned, as this really is a very useful page to link to, but would be much more useful if it were more complete. One additional myth that I'd also like you to cover:

In the Jones/Mann report "Climate Over Past Millennia", the point is made that "Frost fairs (and roasting oxen on the Thames) have been greatly exaggerated as an indicator of climate because:

"River Thames freeze-overs (and sometimes frost fairs) only occurred 22 times between 1408 and 1814 [Lamb, 1977] when the old London Bridge constricted flow through its multiple piers and restricted the tide with a weir. After the bridge was replaced in the 1830s, the tide came farther upstream, and freezes no longer occurred, despite a number of exceptionally cold winters. The winter of 1962/1963, for example, was the third coldest in the central England temperature (CET) record (the longest instrumental record anywhere in the world extending back to 1659 [Manley, 1974; Parker et al., 1992]), yet the river only froze upstream of the present tidal limit at Teddington. The CET record clearly indicates that Thames (London) ''frost fairs'' provide a biased account of British climate changes (let alone larger-scale changes, see Figure 2c) in past centuries."

When I make these points to GW sceptics they almost always say:

1) The Thames barrier also constricts flow, so what's the difference; and

2) There are *no* rivers in Britain, however narrow, on which the ice has been so thick that it has been possible to roast oxen on it, in living memory (not even in 1962).

Please could you refulte these points?

Also, on the radio today I heard a sceptic who was presented as an "expert" claiming that in medieval times the climate was 3C warmer than today (in global mean temperatures then were cooler than today), so please add that to your list as well.

Anonymous said...

Several more myths heard on the radio today:

1) Oxygen levels in the atmosphere are not falling. If atmospheric CO2 levels were rising because of burning fossil fuels then Oxygen levels would fall.

2) The warming in the last century has "only" been 0.8C, which is nothing - if on any given day the temperature were to rise by only 0.8C, no-one would even notice.

3) The Maldives are a large group of coral islands that at their highest reach 6 feet above sea, so if any spot on earth is going to detect rises in sea level, this must be it. When monitoring equipment became available just after world war 2 it was promptly installed there. Since then there have been upwards and downwards random drifts of a few inches from time to time but no trend of any sort has been observed.

4) Environmental scientists have a vested interest in bad news because this is the most reliable way of securing funding.

5) When plankton first evolved the sea was far more acid than today, so the scientists who say that the increasing acidity of the sea that is predicted as a result of global warming will wipe out plankton don't know what they're talking about.

6) Global temperatures fell every year between 1940 and 1970, and during that period CO2 emissions were rising rapidly, ergo the greenhouse effect is a fallacy.

7) It doesn't matter what we do to reduce emissions, because human population growth will ensure that anything we do to reduce them will be a drop in the ocean in comparison with the inevitable rises. Ergo, you may as well give up trying.

8) In the 1950s all environmental scientists agreed that DDT would lead to acid rain, which would wipe out the entire German Black Forest and many other forests all over the world. Nothing of the sort has happened, the only effect of banning DDT has been a huge rise in the incidence of malaria. Ergo consensus about anything among environmental scientists is likely as not to mean they are wrong.

9) (Similarly to 8 above), if the entire ozone layer were to disappear, that would be the equivalent of everyone merely moving 60 miles further south, so nothing serious. But banning CFCs has resurrected all the problems of fire (hydrocarbons) and toxicity that CFCs had been designed to overcome. Ergo a triumph of irrationalism over good science that is typical of "environmentalism".

10) Contrary to the consensus, there have indeed been many rapid rises and falls in temperature in the past.

Dave