I don't know what rock Anthony's been hiding under all this time. (Despite his recent misplaced outrage, he can't have read any of the previous IPCC reports.) It's not as if he doesn't boast that his blog is "...the world's most viewed climate website" - which is, of course, wrong. WUWT may be the world's most viewed anti-science website, but it would be most inaccurate to describe WUWT as a "climate" website. At best it's a disinformation resource for hard line climate science deniers and extremist right wing ideologues.Back to the smog. There was a paper presented by O'Dowd et al at a recent AIP international conference. The paper was called: Cleaner air: Brightening the pollution perspective? Here is the abstract (my paras):
Clean-air policies in developing countries have resulted in reduced levels of anthropogenic atmospheric aerosol pollution. Reductions in aerosol pollution is thought to result in a reduction in haze and cloud layers, leading to an increase in the amount of solar radiation reaching the surface, and ultimately, an increase in surface temperatures.
There have been many studies illustrating coherent relationships between surface solar radiation and temperature however, a direct link between aerosol emissions, concentrations, and surface radiation has not been demonstrated to date.
Here, we illustrate a coherence between the trends of reducing anthropogenic aerosol emissions and concentrations, at the interface between the North-East Atlantic and western-Europe, leading to a staggering increase in surface solar radiation of the order of ∼20% over the last decade.
A couple of things are of interest. Firstly, the paper seems to have put a number on the amount by which reduction in aerosols has contributed to an increase in surface solar radiation. Secondly they appear to be defining an area to which the number applies: the "interface" between the North-East Atlantic and western-Europe. I'm not sure what they mean by that exactly. Probably they are referring to an area of land and ocean and maybe have a map in the paper itself, or the presentation. They probably indicate a time period in the paper, too. Could be since the 1960s, which is when most developed nations started to introduce clean air regulations.
The comments are weird.
Anthony Watts rejects the Greenhouse Effect and becomes a Little Ice Age Bouncer
Anthony Watts is now stepping away from his acceptance of the greenhouse effect. See his inline response to this comment:
August 19, 2013 at 1:02 pm If i get this right, industrial pollution masked the natural warming from the Little Ice Age and the clean air initiatives caused the earth temperatures to rebound to normal levels.
REPLY: Bingo. – Anthony
There are more "it's magic" Little Ice Age Bouncers in among the comments, like RobRoy, who says:
August 19, 2013 at 1:13 pm That natural warming trend seen in the temp records as recovery from the LIA is so often dis-regarded. How many times do warmist types crow over record high temps. Or a record in record high temps. Record high temps would be expected with even with ZERO CO2 effects, through the oft forgotten natural warming trend we have enjoyed since the LIA.
WUWT-ers and aerosols
Lots of WUWT commenters have never heard of the fact that aerosols reflect incoming solar radiation. You've got to wonder at their ignorance, particular that displayed by the WUWT regulars. For example Peter Miller says:
August 19, 2013 at 1:23 pm Seems to make a lot of sense, so the Global Warming Industry will do their very best to ensure this theory is stillborn. C’mon trolls, do your best..
Some of them have read about this before but don't accept the idea. Mike Jonas says:
August 19, 2013 at 1:42 pm Count me out. This smells just like the claims that the ~1940-70 cooling was caused by (man-made, unmeasured) aerosols. This hypothesis only runs marginally OK from ~1940 onwards. It has no explanation for the ~1910-40 warming, or for the cooling before that. To me, it’s a non-starter.
Cleaner air is down to technology, not regulation?
One person has decided that regulations had nothing to do with cleaning up air pollution. They put it all down to technology. Chip says:
August 19, 2013 at 4:32 pm I would disagree with one point. The air didn’t get cleaner because of laws, but because technology and wealth enabled us not to pollute.
Anthony Watts is unfamiliar with scientific conferences
Anthony Watts understands very little about scientific research. He mistakes the conference paper for a peer-reviewed journal article, responding to a query from John W, who asks:August 19, 2013 at 1:51 pm Is this a peer review paper….? I could not tell from the link.
REPLY: yes, it is in the American Institute of Physics (AIP) website – Anthony
A few more choice comments from WUWT
A few more comments - chosen for different various reasons, mostly amusement:
Other_Andy asks about UHI:
August 19, 2013 at 2:15 pm Also wondering, as many stations are in or near cities\ airports, how this will affect UHI for weather stations.
ntesdorf's brain can't conceive that more than one thing affects climate:
August 19, 2013 at 3:32 pm This theory is far more convincing than the CAGW due to CO2 and other ‘greenhouse’ gases. However, first, I would like to check some temperature records that have not been surgically renovated to support the CAGW cause..
highflight56433 reckons scientists should not be the ones reviewing science (he probably thinks it should be judged by the scientific illiterati):
August 19, 2013 at 8:43 pm …peer review? Like having 12 bank robbers as jurors to pass judgment over a bank robbery case.
In fact that thread is so chock-full of denier weirdness I'm having a hard time picking out the most choice comments.
Colin O'Dowd, Darius Ceburnis, Aditya Vaishya, S. Gerard Jennings, and Eoin Moran (2013) Cleaner air: Brightening the pollution perspective? AIP Conf. Proc. 1527, pp. 579-582; doi:http://dx.doi.org/10.1063/1.4803337
I noticed that paper and was a little uncertain about the results myself. When I looked at the Wild et al. (2012) paper it seems very clear that they're arguing that this can influence surface warming, but it wasn't clear what the average net effect was. There seemed to be some increase in albedo from aerosols, but it didn't seem clear by how much this effect could change the net amount of solar energy absorbed globally by the climate system (which seems to be what is actually important).
ReplyDeleteYes, the abstract doesn't give any indication of the global effect. There are other papers that discuss this.
DeleteFor example, Kaufmann et al (2011) and Smith et al (2011) and others were discussed here on Skepticalscience.com. Kaufmann got a bit of publicity at the time. I'm not sure how well their results hold up. I seem to remember some discussion about their findings and I know other people don't necessarily attribute recent surface temperature changes in the same way. Aerosols dissipate quickly and don't mix well, not like CO2. So it wouldn't be all that easy to put a global figure on the effect. SO2 gets washed out of the air fairly readily I think.
Here's an older paper on SO2 from a health perspective.
I had an exchange via e-mail with one of the authors of the "Cleaner Air" paper, and he is adamant it has been wildly misinterpreted by the denialati.
ReplyDeleteAnyone can approach the authors and prove me wrong.
Have the denialiti ever interpreted a scientific paper correctly - either knowingly or unknowingly? They'd be condemned by the Illiterati if they ever dared to use their noggin before tapping furiously on their keyboard.
DeleteI had assumed it was being somewhat/wildly mis-interpreted given that the paper actually says
Deletepotential dampening of global warming by a renewed dimming could only be temporary, and greenhouse gases will ultimately become the sole major anthro- pogenic forcing factor of climate change.
It would be quite interesting to communicate with the authors directly. May do so.
Some of the paper is common to the last statement of the Royal Irish Academy on climate change.
Deletehttp://www.ria.ie/about/our-
work/committees/committees-for-science/climate-change/statements-(1).aspx
This is a surprise. Watt's is both demolishing the skeptic argument that the decline in temperature between the 1940s and 1970s even though CO2 concentration was rising disproves anthropogenic global warming, and implicitly arguing for a large climate sensitivity.
ReplyDeleteThere are several studies, for example http://geotest.tamu.edu/userfiles/88/climate_sensitivity_and_thermal_2002.pdf, that show that if thermal inertia is high, so is climate sensitivity. If the small change in natural forcing since the Little Ice Age is still causing prolonged warming, sensitivity must be huge.
Must be magic that CO2 has no effect.