So much for the theory that AGW increases water vapor and positive feedback

The Atmospheric Circulation system with associ...

The Atmospheric Circulation system with associated pressure belts and latitudes (Photo credit: Wikipedia)

I liked this part:

According to the study an important issue remains as to why the poleward expansion is largest in autumn, and there is still uncertainty about the role of external forcings – such as greenhouse gases – as climate models underestimate the southward expansion of the Hadley cell edge.

From CSIRO Australia

Southern Hemisphere becoming drier

A decline in April-May rainfall over south-east Australia is associated with a southward expansion of the subtropical dry-zone according to research published today in Scientific Reports, a primary research journal from the publishers of Nature.

CSIRO scientists Wenju Cai, Tim Cowan and Marcus Thatcher explored why autumn rainfall has been in decline across south-eastern Australia since the 1970s, a period that included the devastating Millennium drought from 1997-2009.

Previous research into what has been driving the decline in autumn rainfall across regions like southern Australia has pointed the finger at a southward shift in the storm tracks and weather systems during the late 20th century. However, the extent to which these regional rainfall reductions are attributable to the poleward expansion of the subtropical dry-zone has not been clarified before now.

Mr Cowan said rainfall patterns in the subtropics are known to be influenced by the Hadley cell, the large-scale atmospheric circulation that transports heat from the tropics to the sub-tropics.

“There has been a southward expansion of the edge of the Hadley cell – also called subtropical dry-zone – over the past 30 years, with the strongest expansion occurring in mid-late autumn, or April to May, ranging from 200 to 400 kilometres,” Mr Cowan said. The CSIRO researchers found that the autumn southward expansion of the subtropical dry-zone is greatest over south-eastern Australia, and to a lesser extent, over the Southern Ocean to the south of Africa.

“The Hadley cell is comprised of a number of individual branches, so the impact of a southward shift of the subtropical dry-zone on rainfall is not the same across the different semi-arid regions of the Southern Hemisphere,” says CSIRO’s Dr Wenju Cai.

The researchers tested the hypothesis that the dry-zone expansion would give rise to a southward shift in the average rainfall during April and May, and questioned how rainfall across semi-arid regions, including southern-coastal Chile and southern Africa, would be affected.

“During April and May, when the dry-zone expansion is strong, rainfall over south-eastern Africa, south-eastern Australia and southern-coastal Chile is higher than over regions immediately to their north,” Dr Cai said.

Using high-quality observations and an atmospheric model the CSIRO team found that for south-eastern Australia, up to 85% of recent rainfall reduction can be accounted for by replacing south-eastern Australia rainfall with rainfall 400km to the north. Such a southward shift of rainfall can explain only a small portion of the southern Africa rainfall trend, but none of the autumn drying observed over southern Chile.

“For south-east Australia, autumn is an important wetting season,” Dr Cai explained. “Good autumn rainfall wets the soil and effectively allows for vital runoff from follow-on winter and spring rain to flow into catchments.”

According to the study an important issue remains as to why the poleward expansion is largest in autumn, and there is still uncertainty about the role of external forcings – such as greenhouse gases – as climate models underestimate the southward expansion of the Hadley cell edge.

This research was conducted through CSIRO’s Water for a Healthy Country Flagship, and was funded by the Goyder Institute for Water Research and the Australian Climate Change Science Programme. Wenju Cai, Tim Cowan and Marcus Thatcher are from CSIRO’s Marine and Atmospheric Research division.

###

UPDATE:

Some commenters can’t look beyond the title and see the bigger picture, so here’s an update just for them. Note that the study deals with the Hadley cell, which is NOT regional, but hemispherical. They looked not only at Australia, but also rainfall in southern-coastal Chile and southern Africa.

This is where I was coming from, which I thought would be obvious to anyone who’s been following the positive water vapor feedback issue for any length of time.

http://www.gfdl.noaa.gov/bibliography/related_files/hall0001.pdf

===============

Abstract. Using two versions of the GFDL coupled ocean-atmosphere model, one where

water vapor anomalies are allowed to affect the longwave radiation calculation and one

where they are not, we examine the role of water vapor feedback in internal precipitation

variability and greenhouse-gas-forced intensification of the hydrologic cycle. Without

external forcing, the experiment with water vapor feedback produces 44% more annualmean, global-mean precipitation variability than the one without.

We diagnose the reason for this difference: In both experiments, global-mean surface temperature anomalies are associated with water vapor anomalies. However, when water vapor interacts with longwave radiation, the temperature anomalies are associated with larger anomalies in surface downward longwave radiation. This increases the temperature anomaly damping through latent heat flux, creating an evaporation anomaly.

The evaporation anomaly, in turn, leads to an anomaly of nearly the same magnitude in precipitation. In the experiment without water vapor feedback, this mechanism is absent. While the interaction between longwave and water vapor has a large impact on the global hydrologic cycle internal variations, its effect decreases as spatial scales decrease, so water vapor feedback has only a very small impact on grid-scale hydrologic variability. Water vapor feedback also affects the hydrologic cycle intensification when greenhouse gas concentrations increase. By the 5th century of global warming experiments where CO2 is increased and then fixed at its doubled value, the global-mean precipitation increase is nearly an order of magnitude larger when water vapor feedback is present.

The cause of this difference is similar to the cause of the difference in internal precipitation variability: When water vapor feedback is present, the increase in water vapor associated with a warmer climate enhances downward longwave radiation. To maintain surface heat balance, evaporation increases, leading to a similar increase in precipitation. This effect is absent in the experiment without water vapor feedback. The large impact of water vapor feedback on hydrologic cycle intensification does not weaken as spatial scales decrease, unlike the internal variability case. Accurate representations of water vapor feedback are therefore necessary to simulate global-scale hydrologic variability and intensification of the hydrologic cycle in global warming.

=================

So if positive water vapor feedback were occurring, based on this idea, we’d see an “intensification of the hydrologic cycle”, i.e. more rainfall, runoff, and evaporation. That would apply to the southern hemisphere continents too.

And the researchers by their own admission can’t even fit GHG feedbacks into the Hadley cell migration equation successfully. It is just more evidence of uncertainty in the “settled science” of AGW.

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Climate models fail again!

ericgrimsrud

(((Note to moderator, please discard my first comment and replace it with this one in which I have corrected a typo)).
I don’t get the title of this piece. As the atmosphere gets warmer, it holds more water. But the amount of water in (evaporation) still will equal the amount of water out (condensation. Thus, in very general terms, on the surface of the Earth dry places will tend to get drier and wet places will tend to get wetter (or collect more snow). Therefore, evidence of drier places does not justify the title of this piece – while it might fool the public that does not generally understand what I have said here.

Stephen Wilde

Well, they are moving onto the right track at last but the process they describe has been starting to reverse since around 2000 in my opinion.
And they haven’t made any attempt to identify a natural process that might lead to such observations.
As it happens the shift they describe occurred at a time of high solar activity, generally positive AO and AAO, reducing global cloudiness and a cooling stratosphere.
The evidence is pretty convincing to me that upper atmosphere effects from solar variations are the true natural cause.
All those features are now going in the opposite direction with low solar activity, more negative AO and AAO, increasing global cloudiness and the stratosphere warming a little.

Another example of the challenges of climatology as a generalist discipline. I wrote about these issues with general circulation and specifically the Hadley Cell and the failures of the IPCC and other models as representations of reality years ago and again recently in two articles.
http://drtimball.com/2012/static-climate-models-in-a-virtually-unknown-dynamic-atmosphere/
http://drtimball.com/2012/errors-and-omissions-in-major-tropical-climate-mechanism-invalidate-ipcc-computer-models/
The real travesty is CSIRO and all government run weather and climate agencies are just catching up with what we knew thirty years ago. They are victims of the hijacking of real climatology by the pseudo- climate science of the World Meteorological Organization (WMO) sanctioned IPCC.
Get the government and the politics out of climatology and stop pretending that a specialist in one small part of a vastly complex interconnected system is a climate scientist and we might have a chance at better understanding. Something about not seeing the forest for the trees.

Billy Liar

ericgrimsrud says:
October 4, 2012 at 8:34 am
Quite a lot of what you have said appears to have been lost in translation.

dp

Like Eric I don’t see the connection between this article’s title and decreased humidity in the atmosphere (a negative feedback). I also don’t yet see a positive feedback. What is demonstrated is a change in regional rain fall pattern as a result of changing atmospheric circulation patterns, not atmospheric warming, chaning humidity levels, or increased storm activity. This probably means I need to find and read the original paper. I would also say that if the only thing that changes as a result of heating from increased CO2 is an expansion of the dry zones then we have a problem. That alone is bad enough to be a concern. I hate to invoke the old joke, but this analysis probably needs more grant money to discover the whole truth. The grain belts in both hemispheres are facing significant change if this is an accurate portrayal of the effects of CO2 warming. No feedbacks needed, apparently, as this appears to be a direct affect of CO2 warming warming alone.

MarkW

“over the past 30 years”
Nicely coinciding with the warm cycle of the PDO.
(Yes, I know correlation is not causation. But as I said earlier, it gives you real good clues as to where to look.)

richardscourtney

dp:
re your post at October 4, 2012 at 9:10 am.
Be not afraid. The “study” “demonstrated” nothing. It reported the output of a climate model. None of the climate models (except perhaps one) emulates the climate of the real Earth, so the “study” reports the result of playing a computer game.
As to the “effects of CO2 alone” if their are any then they are too small for them to be discernible.
You say you share the concerns of Eric Grimsrud. That alone should be sufficient to cause you to question your concerns.
I commend you to read the post of Tim Ball (i.e. a real climatologist) at October 4, 2012 at 8:45 am and to study the links he provides. Your fears will be assuaged to give you peace of mind.
Richard

son of mulder

ericgrimsrud says:
October 4, 2012 at 8:34 am
It seems quite consistent to me that as the dry zone moves further south so the amount of water vapour from above the warmer parts of the planet decreases, so more radiation can escape from the more strongly radiating parts of the earth. Hence there might be more water vapour overall but it acts less effectively at producing back radiation and so the overall positive feedback could well decrease.

So much for the title of posts on WUWT having anything whatsoever to do with the study that is discussed in the body of the post!
The article discussed didn’t have anything whatsoever to do with the water vapor feedback. It had to do with region variations in rainfall patterns that are observed and also predicted by climate models.
And, the water vapor feedback is already well-verified by observations as discussed in these two articles, for example:
http://www.sciencemag.org/content/323/5917/1020.summary
http://www.sciencemag.org/content/310/5749/841.abstract

REPLY:
So much for you being able to look at the bigger picture of research. This is where I was coming from:
http://www.gfdl.noaa.gov/bibliography/related_files/hall0001.pdf
Abstract. Using two versions of the GFDL coupled ocean-atmosphere model, one where
water vapor anomalies are allowed to affect the longwave radiation calculation and one
where they are not, we examine the role of water vapor feedback in internal precipitation
variability and greenhouse-gas-forced intensification of the hydrologic cycle. Without
external forcing, the experiment with water vapor feedback produces 44% more annualmean,
global-mean precipitation variability than the one without. We diagnose the reason
for this difference: In both experiments, global-mean surface temperature anomalies are
associated with water vapor anomalies. However, when water vapor interacts with
longwave radiation, the temperature anomalies are associated with larger anomalies in
surface downward longwave radiation. This increases the temperature anomaly damping
through latent heat flux, creating an evaporation anomaly. The evaporation anomaly, in
turn, leads to an anomaly of nearly the same magnitude in precipitation. In the
experiment without water vapor feedback, this mechanism is absent. While the interaction
between longwave and water vapor has a large impact on the global hydrologic cycle
internal variations, its effect decreases as spatial scales decrease, so water vapor feedback
has only a very small impact on grid-scale hydrologic variability. Water vapor feedback
also affects the hydrologic cycle intensification when greenhouse gas concentrations
increase. By the 5th century of global warming experiments where CO2 is increased and
then fixed at its doubled value, the global-mean precipitation increase is nearly an order of
magnitude larger when water vapor feedback is present. The cause of this difference is
similar to the cause of the difference in internal precipitation variability: When water
vapor feedback is present, the increase in water vapor associated with a warmer climate
enhances downward longwave radiation. To maintain surface heat balance, evaporation
increases, leading to a similar increase in precipitation. This effect is absent in the
experiment without water vapor feedback. The large impact of water vapor feedback on
hydrologic cycle intensification does not weaken as spatial scales decrease, unlike the
internal variability case. Accurate representations of water vapor feedback are therefore
necessary to simulate global-scale hydrologic variability and intensification of the
hydrologic cycle in global warming.

So if positive water vapor feedback were occurring, based on this idea, we’d see an “intensification of the
hydrologic cycle”, i.e. more rainfall, runoff, and evaporation. That would apply to the souther hemisphere continents too.

TomRude
lowercase fred

For those who do not see the connection, Eric, dp, the difference is WHERE the moisture is located relative to insolation, the energy input from the sun. If the greenhouse gases are not in the region where most of the energy is coming in, then they cannot trap it, it reflects and re-radiates.

joeldshore

Anthony Watts says:

So if positive water vapor feedback were occurring, based on this idea, we’d see an “intensification of the
hydrologic cycle”, i.e. more rainfall, runoff, and evaporation. That would apply to the souther hemisphere continents too.

There are many things going on, including shifting weather patterns, as described in this study. Surely you are aware of the fact that climate models predict greater drought in some regions? It is not just a uniform increase in precipitation everywhere!
As for intensification of the hydrologic cycle, that has in fact been seen. In fact, on this site some have claimed (in comments if not in the body of posts themselves) that one study by Wentz et al. that shows precipitation increasing MORE than models seem to have predicted (although there are in fact significant uncertainties and variability) is somehow evidence against AGW.
So, the question is which story do you guys want to go with: Is the hydrologic cycle intensifying more than expected or not as expected? And, does either way it turns out somehow lead to the same conclusion (i.e., that AGW is wrong or overstated)?
REPLY: The story is that none of you supposed climate experts have any real clue of how it all works, nor does anybody for that matter, and this is just another example of the uncertainties of a science in its infancy. Reminds me of “knobs”. A few years ago they were predicting “permanent drought” for Australia, now its floods. Sure whatever. See the update above. See also Dr. Tim Ball’s comment. – Anthony

Bill Illis

In August 2012, global water vapour levels were 0.13 mms/m2 or 0.6% above normal – ie. nothing.
Australia’s individual levels are very highly dependent on the ENSO pattern (in La Nina’s, there is more rain and more water vapour and there are lower values during El Ninos) versus some Hadley cell explanation. There is no long-term trend in the ENSO so one would expect no long-term trend in Australia rainfall either.

What they are saying WAS the case when the sun was active.Since 2005 the sun has become inactive and the Hadley -cell is most likely moving equatorward, as the Antarctic vortex expands N.
They are in the past, not the present.. It figures.

Stephen Wilde

When the hydrological cycle intensifies it doesn’t produce more humidity globally if the cycle is faster.
A faster hydro cycle can be larger without increasing humidity because the water is in vapour form for a shorter time.
Nor need it be accompanied by a higher temperature globally as opposed to locally because a faster or larger hydro cycle ejects energy to space faster as a negative feedback.
My position is that solar cycles, ocean cycles AND GHGs all produce a negative system response via a change in the hydro cycle which manifests itself as a change in the global air circulation including the position, sizes and intensities of the subtropical high pressure cells.
However, the contribution from human CO2 emissions would be imperceptible compared to that from sun and ocean variability.

The big problem with increasing the pace in the hydrological cycle is the latent heat, 2500 joule per gram water. I calculated once that in order to keep the relative humidity constant at higher temperatures as per alleged CO2 doubled forcing at the same cycle rate, you’d need something about double the energy that is allegedly avaible for doubling CO2 for the additional evaporation.

The other point is, without extra water to multiply the warming of CO2, CO2 alone doesn’t come close to cause enough heating to match measurements. As the paper said, approximately the correct amount of water is falling Australia, but further to the south (this did not apply to Africa or Chile, but that is possibly a measurement issue ie maybe the rain is falling into the ocean). So at least in Australia there’s no indication of the excess water required to create CO2 warming.

John Trigge (in Oz)

From the rainfall graphs available from the Oz BOM (http://reg.bom.gov.au/cgi-bin/climate/change/timeseries.cgi?graph=rain&area=seaus&season=0112&ave_yr=0), it appears there was an increase in overall rainfall from 1900 – 1970 whilst 1970 onwards shows a decline.
Whilst the study concentrated on our Autumn rainfall, perhaps taking into account ALL available data might be useful to identify causes, particularly cyclic ones.

Dale

They could’ve saved time and money and just asked any Melbournian. We could’ve told them we observed this change. During the 80’s Melbourne’s weather would track in a pretty much Easterly direction from the Great Australian Bight, then in the 90’s our weather would track South-East across Australia bringing hotter drier weather. Then during the 00’s the weather tracks moved further South so now our weather tracks North-East from the direction of Antarctica (reversal occurred about 2008).
You can physically notice the difference as we USED to know we’d have the same weather as Perth 3 days later (Adelaide got it 2 days later). Then we had to start looking at the Western Australia Central Coast in the 90’s. Now we look at what comes out of the Southern Ocean. These last 3-4 years have been cold and wet as a result.

JP

The Southwest US can see this intensification of the hydrologic cycle evertime the Hadely Cell expands into the Desert Southwest during the summer. Heavy thunderstorms, flash floods, and tropical cyclones hitting Baja follow in the wake of this expansion. Downstream, across the Lee of the Rockies, there are drought conditions; but, this is induced by geography more than anything else.

Rosco

Eastern Australia has just experienced 3 of the wettest years in more than a decade including 2012 which was the wettest since the 1974 flood year.
CSIRO abandoned science years ago and now produce propaganda for sale.

Couple of things.
Water vapour ‘feedback’…eh?
So these clowns claim to have detected/measured and fixed a ‘stable’ rate of evaporation from the tropical OCEANS!!! and then proceed to claim that they have detected/measured a deviance from this rate which they assign to ‘greenhouse gases’. Wow.
Blind Freddy (he’s the politically incorrect, dumb Australian who is gifted with seeing the bleeding obvious)…yes Blind Freddy himself could point out that there are major shifts in SSTs in the vicinity of this vast continent which totally and directly affect the rainfall wildly different climate areas.
For instance right now, to the north of Australia the SSTs are unusually cool and the evaporation rates subsequently lower, hence the dry spring we have been having on the northern part of the east coast.
Second thing.
Blind Freddy could also point to the vast swathes of rain falling in the Pacific Ocean to the East of Australia where of course it is not measured by the droughtist, angst ridden CSIRO but goes on it’s merry way into the ocean currents.
The CSIRO really is in the grip of CO2 Warmism, it rides the vagaries of the Australian Climate (land of droughts and floods) like a surfer. It is only interested in funding.

Rosco

Oh – and included in that devastating 1997-2009 millenium drought were the 2001 floods of northern NSW and South East Queensland – road transport severly disrupted due to flooding.
Eastern Australia has seen way above average rainfall since the drought broke in Spring 2009 – especially northern NSW and SE Queensland.
Wivenhoe dam in SE Queensland went from <15 % in Spring 2009 to over 65 % after the 09/10 wet season (Summer here) to 199% in January 2011 where it nearly created an even worse flood disaster because politicians listened to climate scientists claiming it would never rain again and refused to lower what is essentially a flood control dam – then tried to blame the engineers for the politicians stupidity in believing the lie that it would never rain again.
January to June 2012 was the wettest six months since 1974 – despite no major flood event like 2011.
Every major wet season in my life has coincided with LaNina conditions in Eastern Australia.
After 2 major wet years I am hoping that the ENSO meter stays in neutral territory and we have a more normal summer – but I wouldn't bet on it though.

Dale

Rosco:
The paper only takes into consideration up to 2009, just after the Hadley Cell started moving north again. As I noted above, since 2008 Melbournians have started looking at what weather is coming to us from the Southern Ocean instead of what’s coming across WA.

Annie

Dale @ 1:01 pm:
Yes, in Melbourne a few years ago you could always rely on getting a dose of Perth’s weather 3 days later. Not so more recently.

William

What’s the point? As Lindzen has shown. all of the models have feedback from water vapor which is just opposite to the feedback operating in nature. If the models are inherently unreliable, how they change with tweaks of individual model parameters (whether it be in relation to CO2 or water vapor) is irrelevant.

old construction worker

“So if positive water vapor feedback were occurring, based on this idea, we’d see an “intensification of the hydrologic cycle”, i.e. more rainfall, runoff, and evaporation. That would apply to the southern hemisphere continents too.”
The only “positive water vapor feedback” or “intensification of the hydrologic cycle” only happen in the “Gore Effect”.

MonktonofOz

Dear Mr CSIRO, We live in country SE Oz and though I don’t know about the science I can tell you our water tanks are full. Perhaps you could risk leaving your laboratory and get your “model” to stick its head into the tank to check?

kadaka (KD Knoebel)

Once again the task shall fall to CSIRO to show to Australia and the world the proven damages wrought by Anthropogenic Climate Change. The models are in agreement, now backed by real world confirmed evidence. There is only one solution to save Australia from the horrendous ravaging drought to come.
Build more desalinization plants.
Hopefully CSIRO will be able to bring about this certain cure for ACC before the Great Barrier Reef is irrevocably destroyed beyond any hope of recovery, again.

X Anomaly

More or less, here is whats being spoken of:
http://www.bom.gov.au/cgi-bin/climate/change/timeseries.cgi?graph=high_density&area=sth&season=0305&ave_yr=0
Looks like quite a signal, although it is lacking the last 3 years worth of SH autumn data (including this autumn). That’s interesting because there has been plenty of autumn rain during the last three years:
http://www.bom.gov.au/cgi-bin/climate/change/timeseries.cgi?graph=rranom&area=seaus&season=0305&ave_yr=0
with 2010, 2011, and 2012 autumn rainfall anomaly being + 18, 0, and 41 mm respectively.
But that does fit the anthropogenic alarmist dogma, which is why the omit the month of march, because as you can see here (I know, its s good one):
http://www.bom.gov.au/cgi-bin/climate/change/timeseries.cgi?graph=rranom&area=seaus&season=03&ave_yr=0
It’s been bucketing down in march!!!, resulting in record flooding. In fact, the 2012 march rainfall for south eastern Australia was the HIGHEST on record.
Now, for the alarmist at heart, this is not a problem, since it can be argued that the recent March anomalies where due to unseasonal tropical rainfall, and that of course can be blamed away on global warming.
One problem though, do they really expect us to believe they know the source of all the March rainfall events since 1900? I mean seriously, who the f@@k are these people!
Tropical, extra tropical, sub polar, etc…? You only have that data since the 1980’s, which is why I’m still looking for that radial button which diverts funding from these cargo cult hacks.

Mark

Rosco, Nelson, and others have got that right. CSIRO “science”: By the government, for the government. The propaganda that CSIRO churns out, at the public’s expense, is no more reliable than its models. They don’t even have the right balance of energy.
http://www.climatedepot.com/a/17674/Climate-scientist-Dr-Murry-Salby-explains-why-manmade-CO2-does-not-control-climate
Who cares how one of their internal cogs affects another? Yet, those models are the excuse for building expensive but pointless desalination plants, which have inflated water costs, and our big new tax burden, through which power bills have jumped dramatically.
This must be the payoff of “Trickle Down Government”.

clipe

Oxygen isotopes in tree rings are a good proxy for Amazon precipitation and El Niño-Southern Oscillation variability</code?
http://www.pnas.org/content/early/2012/09/27/1205977109

clipe

Oxygen isotopes in tree rings are a good proxy for Amazon precipitation and El Niño-Southern Oscillation variability
http://www.pnas.org/content/early/2012/09/27/1205977109

Most people are missing the whole point. Is it supposed to be raining more from positive feedback, or less? Are they just changing theories as they go along? First it was droughts, but that didnt work. Then the floods came and that went out the window. Now its been dry in Perth during Autumn and its the Hadley cell.
Why wouldnt you look at this instead, since the warm PDO the Southern Annular mode has been predominately positive.
http://www.lasg.ac.cn/staff/ljp/data-NAM-SAM-NAO/SAM(AAO).htm
Now we are in the Cold PDO, lets see if it responds for the next 30 years the other way. The thing to come out of it is no one knows for sure. They are throwing theories around left right and centre in the hope one is right.

dp

REPLY: The story is that none of you supposed climate experts have any real clue of how it all works, nor does anybody for that matter, and this is just another example of the uncertainties of a science in its infancy. Reminds me of “knobs”. A few years ago they were predicting “permanent drought” for Australia, now its floods. Sure whatever. See the update above. See also Dr. Tim Ball’s comment. – Anthony

Ok – this I can understand. There are a lot of people that are big on decrying the well-understood CO2 heating (as a result of doubling blah blah blah) but can’t begin to get past the 1.2ºC limit of that doubling. Meaning they ignore that a lot of knock-on forcings absolutely have to happen for global warming to be a bother and nobody knows if these forcings are net positive or net negative.
But – according to Planet Earth, that big ball under our feet, and the output created by defective but never the less the very best climate models available, the forcings are not positive else there would not be a growing divergence between projected and observed temperatures.
You will find not shortage of experts who will decry the direct warming of CO2 (which is unimportant and would have happened even without human intervention given the natural growth of CO2) but who cannot close the deal by showing the process by which forcings finish the job CO2 starts (Mosher, for example).

RoHa

Seeing the name “Thatcher” attached to anything connected with climate gives me the shivers.
But I’m sure this stuff is consistent with the AGW conjecture. Everything, no matter what, is.

ericgrimsrud

To Dp,
I have had a go around before with the person named richardscourtney who scolded you above for seriously considering my comment. FYI, in that go around, I learned that he has no demonstratable background in science, in general, and certainly no record of contribution to climate science. In addition, when drawn into a discussion of the simplest aspect of climate science, I found that he cried foul and ran for cover, asking the moderator to ban me instead of him from participation in WUWT. Yet he is encourage to pontificate very regularly at WUWT for reason I do not know. It must have something to do with the clever British put downs that litter his comments. While that are they carry no content and come from nowhere scientific.
On the other hand, I have a very long record of accomplishment in the field of atmospheric science that was been domonstated and can be inspected at ericgrimsrud.com. Therefore, there is a distinct possiblity that you might just happen to be in better company when you also noted that the problem I immediately had with the title of this post.
Cheers to you and, of course, his excellency, Sir Richardcourney, whoever you are.

That’s odd! I am a PhD geoscientist directing a small consultancy in SE Australia specializing for the last 15 years in surface and shallow groundwater management and impact assessment for the mining industry. There is a frequent call for us to construct Cumulative Monthly Rainfall Residual Plots at a wide range of long term rainfall monitoring stations – most BOM (Bureau of Meteorology) stations. We do this in order to better interpret shallow groundwater level trends, small catchment productivity trends etc. above or in proximity to underground mining (which produces mine subsidence). We typically use long term monthly records going back to 1970 – 1980 to establsihed long term mean monthly rainfalls.
In actual fact, in recent years, following the drying trend of the 2001 – 2006 Millenium Drought (which BTW was a drying trend that following an even longer wetting trend) monthly rainfalls (in SE Australia) have moved more or less back into proximity e.g. within one standard deviation, to the long term means of the 1970/1980 – 2011, 30 – 40 year period. There is no evidence of a significant drying relative to the long term means of the last 30 – 40 years except at a very few locations.

Fred Love

Sadly, today’s C(anti-)SIRO creates mountains out of statistical molehills. Try a full set of data from 100+ years, eg., Condobolin in the wheat belt. Total annual rainfall trend (1890 to 1911) is upward and autumn rainfall shows no trend at all. Even from 1970- there is no “drying-out” if 2008-11 is included. These people are shameless propagandists, not scientists.

As a resident of Perth, Western Australia, it has seemed to me that these days we get rain from warm tropical moist air more frequently than we used to, and rain from southern cold fronts less frequently.
So I’d agree that the weather patterns seem to be moving south, away from the equator.

tty

These people badly need to read up on world climates:
“semi-arid regions, including southern-coastal Chile ”
Southern coastal Chile is one of the wettest places in the World. Presumable they are thinking of northern coastal Chile, which is indeed arid.

spartacusisfree

There can be no GHG-AGW because GHG thermal emission from the atmosphere annihilates that band emission from the Earth’s surface.
The physics is very simple: the net UP IR in any wavelength interval at the surface is the vector sum of the Poynting vectors arriving at that point. This is required by Poynting’s Theorem, the most basic axiom derived from Maxwell’s Equations.
Engineers like me calculate this from the difference of the S-B emission from the bodies in radiative equilibrium. So every GHG atmospheric thermal emission band reduces the equivalent emission from the surface. The Aarhenius GHG blanket is not possible and anyone who believes in it betrays their lack of basic physics’ knowledge.
The addition of ‘back radiation’ to net UP IR in the Trenberth ‘Energy Budget’ recreates the UP Poynting vector, most of which can do no thermodynamic work.
The real GHE is mostly the result of the rise in temperature needed to overcome reduced surface emissivity. Check this argument with any physics’ professional and they will confirm I am right.

richardscourtney

ericgrimsrud:
At October 4, 2012 at 8:16 pm you claim

On the other hand, I have a very long record of accomplishment in the field of atmospheric science that was been domonstated (sic) and can be inspected at ericgrimsrud.com.

Allow me to save people the time of conducting that “inspection” by listing your entire
very long record of accomplishment in the field of atmospheric science.
1.
Read SKS.
2.
Wrote an ebook that gets almost everything wrong.
3.
Paid to publish the ebook at your own expense.
4.
Visited WUWT and made a fool of yourself in various ways; e.g. called davidmhoffer and myself “feces” for pointing out your mistakes.
5.
At October 4, 2012 at 8:16 pm on this thread claimed to have a very long record of accomplishment in the field of atmospheric science.
Richard

Another nail in the GHG theory. Keep them coming.
Increased water vapour in the atmosphere will adsorb more SIR and emit more LIR to cause more evapouration etc.

Patrick

Oh dear! More computer simulated “science” from the CSIR “Cane Toads are good” O. Along with my sides, my Playtex 24 girdle is showing signs of wear from laughter!

wayne Job

“External forcings such as green house gases”. What sort of statement is that! External to what? The world, are these CO2 molecules attenuated out in space and emitting evil forcings at the Earth. My understanding of a forcing is the gaining of entry through a door by breaking it down.
Using real speak it could be interpreted as “external forces such as the sun”
That however may lead to a lesser career path and pay cheque. These people really need to just do the science and stop the BS.

D Böehm

ericgrimsrud says:
“I learned that (Richard Courtney) has no demonstratable background in science, in general, and certainly no record of contribution to climate science.”
Where did you “learn” that? If I am not mistaken, Mr Courtney is a published, peer reviewed author.
You may post your apology here.

Bill Illis

Here is the current water vapour levels back to 1948 and the IPCC water vapour forecast which will be in AR5 going out to the year 2100.
http://s19.postimage.org/pk8wtzxqr/WV_IPCC_AR5_Forecast_2100.png
And then more of a close-up going out to just 2020 where we can also see that the ENSO is the dominant control mechanism of global water vapour levels (which lag behind it by 3 months – this is one of the most important climate drivers there is, global water vapour levels – this relationship is taken advantage of by the climate science community since any paper dealing with water vapour levels deliberately starts their analysis in a La Nina and ends in an El Nino so they can show an increase in water vapour levels – they should instead be trying to understand why the ENSO is so dominant here and what the implications of that are.)
We can also see that the “hindcast” of IPCC AR5 which should be using actual observational data up to about 2010 is already way off of the actual values. IPCC AR5 has water vapour levels up by 5.4% already and have it increasing by 23.5% by 2100 (similar to the theory that water vapour should increase by about 7.0% per 1.0C increase in temperatures – so they have just built this theory directly into the models – it is needed to get to 3.0C per doubling – perhaps that is why the ENSO relationship is so downplayed – because it would throw a wrench into 3.0C per doubling if the ENSO continues its historic pattern of no trend over the long-term.)
The theory is missing something very important here.
http://s19.postimage.org/rnjc1nxjn/WV_IPCC_AR5_Forecast_ENSO_Sept2012.png