IS the ongoing drought in the Murray-Darling Basin affected by climate change? The simple answer is that there is no evidence that CO2 has had any significant role. Like it or not, that is the science.
In fact, the drought was caused by an entirely natural phenomenon: the 2002 El Nino event. This led to particularly low rainfalls across eastern Australia. The subsequent years were either neutral or weak El Nino conditions. Significantly, neutral conditions are not sufficient to break a drought. In 2006, we had a return to El Nino conditions which further exacerbated the drought. What we didn’t have was a strong La Nina.
Last year finally brought a La Nina event but it was relatively weak. It produced a number of major storm events in coastal areas and some useful rainfall in the Murray-Darling basin and elsewhere. Approximately half of NSW drought-declared areas were lifted out of drought (albeit into “marginal” status) and Sydney’s water supply doubled in the space of a few months.
This was the first rain-bearing La Nina since 1999 but proved insufficient to break the drought. In short, the drought was initiated by El Nino, protracted by further El Nino events and perhaps more importantly, the absence of substantial La Nina events.
Despite the known causes of the drought, many have claimed that CO2 emissions are to blame. There have been arguments put forward to justify this claim, all eagerly adopted by various groups, but none of which have serious merit.
A key claim is that the multiple occurrence of El Nino is a sign of climate change. This is speculative at best. Recent analysis showed the nine-year absence of La Nina was not unusual. In fact long-term records demonstrate alternating periods of 20-40 years where El Nino is dominant, followed by similarly extended periods where La Nina dominates. Ominously, the data demonstrates that it is possible to go 14-15 years without any La Nina events. The consequent drought would be devastating but entirely natural.
The observation that El Nino and La Nina events cluster on 20-40 year, multi-decadal timescales is an important one. It demonstrates that Australia should always expect major changes in climate as a function of natural variability. When viewed in this light, the drought is most likely a recurring feature of the Australian climate.
A more recent claim is that higher temperatures are leading to increased evaporation of moisture. The weather bureau acknowledges that rainfall from September 2001 until now has not been the lowest recorded, however much has been made of the fact that consequent inflows have been the lowest. It has been claimed increased evaporation, driven by climate change, can make up this discrepancy. Indeed, Wendy Craik, the chief executive of the Murray Darling Basin Commission has stated that temperatures were warmer, leading to more evaporation and drier catchments.
This is disturbing to hear from the head of the MDBC, as it is completely at odds with the known physics of evaporation. While it sounds intuitively correct, it is wrong.
When soil contains high moisture content, much of the sun’s energy is used in evaporation. Consequently, there is limited heating of the surface. When soil moisture content is low (as occurs during drought) nearly all of that energy is converted into heating the surface, and air temperatures rise significantly. Consequently, higher temperatures are due to the lack of evaporation, not a cause of significantly higher evaporation.
Cloud cover also provides a major control on air temperatures. El Nino delivers less rainfall but also less cloud cover. This has a major impact on the amount of the sun’s energy reaching land; far greater than the trivial increase in radiant energy caused by increased CO2. Again, in the absence of soil moisture, air temperatures increase.
These are known and accepted processes of environmental physics and are not contentious. They are ignored because they detract from the simple message that we should sign up to the concept of “dangerous climate change” and an emissions trading scheme. After all, who would pay for carbon emissions if they were not proven to be detrimental? Who would provide extra funds for climate change science if it wasn’t a proven significant factor compared to natural climatic variability?
None of the above is to say that CO2 is not having some effect; the atmospheric CO2 concentration has risen and this is largely attributable to anthropogenic emissions. CO2 is a radiatively-active gas and leads
to a minor increase in downward radiation. However, there is no evidence that this is in any way significant, especially when compared to the naturally varying processes that dominate rainfall variability and evaporation.
We do know why inflows are so low and why various ecosystems of the Murray-Darling are in crisis: the system is over-allocated and has experienced a growth in groundwater extraction and in the number of farm dams preventing rainfall from becoming run-off. This is due to a failure of planning, management and leadership from the relevant authorities. Under these conditions, when a prolonged drought strikes, the system collapses.
This is a man-made problem but not one that is attributable to CO2.
Craik is not alone in her desire to view CO2-induced climate change as proven and affecting the drought. Numerous politicians, environmentalists and especially scientists have made spectacular leaps of faith in their adherence to the doctrine of climate change over recent years, too many to document here. However, the most literally fantastic claim on climate change must go to Kevin Rudd, who has guaranteed that rainfall will decline over coming decades; one can only assume he’s based his view on deficient climate models and bad advice.
Perhaps our leading climate authorities who have played such a prominent role in fomenting speculation about climate change, and who apparently adhere to the notion that climate is amenable to prediction, should also point out that these models cannot reproduce the observed multi-decadal variability of El Nino and La Nina in anything like a realistic manner.
Given the uncertainty of El Nino and La Nina behaviour, one clearly cannot predict the future. There is no direct evidence of CO2 impacts on the drought, nor is there any rational basis for predicting rainfall in 30 years time. One just hopes that sensible and sustainable management from our leaders will enable struggling rural communities to weather the vagaries of climatic and political extremes.
Stewart Franks is a hydroclimatologist and an associate professor at the University of Newcastle School of Engineering. He is president-elect of the International Commission on the Coupled Land – Atmosphere System.
This article has been republished from The Australian with permission from the author.
Emissions not making rivers run dry, The Australian, Stewart Franks, September 12, 2008
Jan Pompe says
It’s a good article and here are the ENSO events he mentions.
the lorax says
It may be true that AGW has done nothing to contribute to the drought, however a study pruduced by the University of queensland has shown a cuasul link between vast land clearing and an increase in surface tempretures int eh basin of up to 2 deg C, worse than climate change. The impacts are the same with evaporation etc. Also large areas of the basin have been cleared of stable long term species to crops and meat that export water from the region, coupled with this is the replacement of mature stable forest with regenrating water hungry regroth -that is often cleared and then it regrows as another thirsty young forest. Add to this the changed fire regime ( fire exclusion) and we have a forest thicvkening which requires more water, the system has been knocked out of balance and is now trying to find its new equilibrium and that will keep changing whilst we mess with it.
What causes ENSO?
And to think that engineers invented risk mangement to compensate for uncertainty. Much easier to assume it away or blame it on El Nino or if that doesnt work decadal oscillations. We might expect that scientists have different standards of proof to risk managers, but not engineers. They have different responsibilities.
Australia has had a history of drought, the Federation Drought over 100 years ago and before the rise of CO2 concentrations and modern day land clearing, was one where the rivers in western Queensland are reported to have dried up; at Bourke, the Darling River virtually ran dry. Further south, towns near the Murray River such as Mildura, Balranald and Deniliquin – at that time dependent on the river for transport – suffered badly.
Ironically the Federation drought began a focus on irrigation, especially in the three states through which the Murray River flows: after the next severe drought in 1914 that the River Murray Commission was created, which is known as the Murray Darling Basin Commission.
Jan Pompe says
bazza a good engineer first properly assesses the risk before working on how to manage it. It’s an essential part of risk management. This is precisely what he is doing even if you find it difficult to understand it that way. It’s really poor form for an engineer to base his assessment on old wives tales.
Bob the engineer says
Bazza – looking at Franks’s website he is a science graduate and only works in engineering.
Franks does indeed do the risk assessment; it’s what he gets paid for; but he also has the theoretical nous to back up the empirical based risk work;
More good news; the SOI is increasing positive;
I don’t believe it; the ad hom starts already; Franks has a PhD in atmospheric/surface coupling and an honours degree in atmospheric hydrological processes, which puts him about a million miles in front of Hansen, Schmidt, Flannery and other AGW luminaries.
What causes ENSO?
Jan Pompe says
Bob “a science graduate and only works in engineering”
Know that type well.
NT; Bob Tisdale has some interesting ideas about ENSO; it’s effects and causes;
http:bobtisdale.blogspot.com/2008/05/annual-and-long-term-impacts-of-el.html (// excluded)
This paper is also helpful, although if it contradicts Bob I don’t won’t to know about it;
http:www.cdc.noaa.gov/people/gilbert.p.compo/Newmanetal2003.pdf (// excluded)
NT the last cool phase PDO in the pacific coincided with the much heavier rainfall in the MDB when the Murray flooded many times.
This C/Phase PDO started in 1945 and ended in 1978 just like the rainfall.
The cool phase PDO seemed to produce stronger and more regular la nina events particularly in the 1950’s and 70’s, so I’d say c/phase PDO’s produce more La nina events while warm phase PDO’s produce more El nino events.
Neville, I have read about the relationship between PDO and El Nino. It is not so clear, it could be that a cluster of El Ninos is a positive PDO. PDO doesn’t necessarilly cause El Nino (well that’s what I have read).
Does anyone know if increasing global temps will lead to more likelihood of El Nino conditions. I think this is where the association between drought and CO2 (or more specifically AGW) comes from.
Cohenite I would suggest Bob do a more thorough statistical analysis, rather than eyeballing graphs.
Franks’s statements are sound. The less alarmist parts of the Bureau of Met seem to agree with certain of his points.
From Journal of Climate, August 2007 …
Sensitivity of Australian Rainfall to Inter–El Niño Variations
GUOMIN WANG AND HARRY H. HENDON
Bureau of Meteorology Research Centre, Melbourne, Australia
(Manuscript received 12 June 2006, in final form 5 December 2006)
Australia typically experiences drought during El Niño, especially across the eastern two-thirds of the continent during austral spring (September–November). There have, however, been some interesting departures
from this paradigm. For instance, the near-record-strength El Niño of 1997 was associated with near-normal rainfall. In contrast, eastern Australia experienced near-record drought during the modest El Niño of 2002. This stark contrast raises the issue of how the magnitude of the drought is related to the character and magnitude of El Niño, for instance as measured by the broadscale sea surface temperature (SST) anomaly in the equatorial eastern Pacific. Internal (unpredictable) atmospheric noise is one plausible explanation for this contrasting behavior during these El Niño events. Here, the authors suggest that Australian rainfall is sensitive to the zonal distribution of SST anomalies during El Niño and, in particular, the greatest sensitivity is to the SST variations on the eastern edge of the Pacific warm pool rather than in the eastern Pacific where El Niño variations are typically largest. Positive SST anomalies maximized near the date line in 2002, but in 1997 maximum anomalies were shifted well into the eastern Pacific, where their influence on Australian rainfall appears to be less. These findings provide a plausible physical basis for the view that forecasting the strength of El Niño is not sufficient to accurately predict rainfall variations across Australia during El Niño.
What causes ENSO?”
Good Question NT…. It’s a natural climate system that has nothing to do with CO2…..
Why? What do you think it is?
ENSO is related to ocean surface water temperatures. Yes, it is a natural phenomena. Would you not expect a warming climate to warm the oceans further, hence making El Nino vents more common?
From the NOAA CPC website:
“What is the relationship between El Niño/La Niña and global warming?
The jury is still out on this. Are we likely to see more El Niño’s because of global warming? Will they be more intense? These are questions facing the science community today. Research will help us separate the natural climate variability from any trends due to man’s activities. If we cannot sort out what the natural variability does, then we cannot identify the “fingerprint” of global warming. We also need to look at the link between decadal changes in natural variability and global warming. At this time we cannot preclude the possibility of links but it is too early to say there is a definite link.”
So the point of this post is somewhat pointless. It’s also slightly misleading as it says our droughts are caused by El Nino, not AGW, when the causes of El Nino are not entirely known and there is the possibility that El Nino’s will increase over time… SO the question really should be, “Does AGW mean more (or more stronger) El Nino events?”
NT, Stewart Franks clearly states that with the current evidence we can’t link AGW to stronger El Nino events. Therefore your statement:
“So the point of this post is somewhat pointless.”
is wrong because many people are making this connection with the mistaken belief that there is evidence.
Joel, NOAA disagrees.
And Stewart Franks doesn’t state that. Or at least he’s not clear.
“A key claim is that the multiple occurrence of El Nino is a sign of climate change. This is speculative at best. ”
This is the closest he comes.
He may disagree with NOAA, but to say that there is no evidence is not correct. we haven’t found a link bewteen AGW and El Nino, but that’s not to say it doesn’t exist.
I’m surprised Cohenite, Louis Hissink, and Bird haven’t jumped on this comment:
“None of the above is to say that CO2 is not having some effect; the atmospheric CO2 concentration has risen and this is largely attributable to anthropogenic emissions. CO2 is a radiatively-active gas and leads to a minor increase in downward radiation.”
Why aren’t you all claiming that he is wrong and that CO2 is from the ocean, or that you can’t radiate downwards or whatever. I thought you were all skeptics! Come on! put on your Skeptivision (TM) goggles he’s obviously part of the grand conspiracy 🙂
Louis Hissink says
“A key claim is that the multiple occurrence of El Nino is a sign of climate change. This is speculative at best. ”
I presume the key claim is made by AGW proponents but that is much like saying that climate change occurs because it changes.
Until a link is found, it does not exist, but to presume a link does exist is simply pseudoscience.
This is not surprising as AGW is pseudoscience.
Presume what you want Louis
NT, let’s argue global warming and this interglacial compared to previous interglacials.
In previous interglacials the sea levels were much higher somewhere between 3 m and 20 metres higher than at our present time, Greenland and antartica perhaps melted to near completion.
No advanced human activity causing this so it must have been natural climate change.
Also I still ask why was the sea around Australia at least 1.5metres higher as recently as 4,000 years ago yet we have dropped then returned to the present day level.
This warming and cooling seems to be something that nature can accomplish without the help of mankind and over a very short time frame.
NT; that’s neat; the ad hom won’t wash with Stewart, so claim him as one of your own.
El Nino, ENSO and AGW; since you didn’t like Bob Tisdale’s graphs, there is a plethora of papers linking ENSO with circulation variations; the grandaddy of circulation effects is perhaps the upwelling exchange between the cold deep ocean water and the warmer surface water; this has nothing to do with AGW; there was a major decrease in this upwelling in 1976 in what is known as the Great Pacific Climate Shift; McLean and Quirk put out a paper on this;
http:mclean.ch/climate/Aust_temps_alt_view.pdf (// excluded)
As have McPhaden and Zhang;
http:www.ncbi.nlm.nih.gov/pubmed/11832936 (// excluded)
The 1976 cessation began a 20 plus year decline in the upwelling and coincided with +ve El Nino PDO period culminating in the super El Nino of ’98; in their 2004 paper McPhaden and Zhang (GL paper 10.1029/2004GL020727,2004) note;
Recent observations indicate that the shallow meridional circulation in the tropical Pacific Ocean has rebounded since 1998, following 25 years of significantly weaker flow. M & Z compared the 5-6 year average conditions before and after 1998 in the Pacific and report a recent increase in equatorward flow in the upper ocean linked to a change in the Pacific Decadal Oscillation. The circulation increase is also related to a strengthening of the trade winds, changes in the equatorial sea level, and the development of anomalously cool equatorial Pacific sea surface temperatures. The authors suggest that the changes may have affected the global climate and Pacific marine ecosystems. A pattern of stronger circulation was the norm prior to 1976-77 (when La Nina and a -ve PDO dominated), when weaker overturning flow began to dominate the Pacific. the researchers suggest the abruptness of the circulation recovery in 1998 obscures the presumed manmade warming trends indicated in the instrumental records from the tropical Pacific.
Now, recovery obscuring “presumed manmade warming trends” has been comprehensively debunked by lucia;
With the ENSO removed, so to is the upwelling effect; the temperature trend is down; ENSO is not obscuring any man-made heating because there is none.
Jonathan Wilkes says
“This warming and cooling seems to be something that nature can accomplish without the help of mankind and over a very short time frame.”
This is what I’ve been asking a few times myself and so far, no definite or just “no” answer.
Also the increase of CO2 and no corresponding increase of temp. (as predicted by the comp. models) are always conveniently bypassed.
NT asked several times: “what would convince?”
well, some evidence that what is happening (which is very little as far as temperature goes!)
is caused by humans and not just a natural variation of the climate?
Neville, yes you are right. There have been earlier interglacials, althought it didn’t include the loss of ice off Antarctica (that would make sea levels MUCH higher) the sea levels were higher. The last time there was no ice in Antarctica was about 35 million years ago (I think). I am not certain about levels of ice on Greenland 4000 years ago. I would think it was a smaller sheet but that there was ice there.
So yes cooling and warming did happen without our help. There are theories and models as to why that happened. The link between the Milankovitch Cycles and CO2 levels (and CH4 and H2O) in the atmosphere and subsequent albedo changes seems to work well in models.
The recent changes in climate (the recent warming) can’t be attributed to changes in insolation (Milankovitch Cycle changes) however, so are most llikely cause by changes in CO2 and CH4 and albedo.
4000 years ago the climate was warmer (probably) than today, it was probably warmer around 10 000 years ago as well, hence the higher sea levels. I believe these warm periods (either side of the Younger Dryas) form the Holocene Climate optimum… Might have the dates wrong, check up on the dates for the Holocene Climate Optimum, Dryas, and Younger Dryas yourself. I’ll just get yelled at if I get them wrong 🙂
A sea level 3m higher would cause a lot of problems and require the building of substantial sea walls or relocation of buildings and cities.
Cohenite, you know I am better than mere ad homs at random people! I save them for you and Graeme!
So do you find his views… Friendly in this regard? I didn’t quote him out of context and he didn’t have to say all that… So what do you think? Is he wrong?
The problem with El Nino and Ocean Currents is that they are inter-related. One doesn’t necessarilly cause the other. And it is VERY difficult to figure out how AGW will affect ocean currents.
Remember the ocean currents only exist as a response to chemical (giving density contrasts) and temperature differences, and the coriolis effect. Change the temperature and you change (or rather could change) the currents.
I don’t know what AGW will do to El Nino, I am not pretending to. But I can’t imagine it will do nothing. Perhaps the currents will change and move to a new entirely different regime?
Actually I should add that ocean currents probably exist due to other factors as well, that I am unaware of. But the idea that currents exist to transport heat is not contraversial
“well, some evidence that what is happening (which is very little as far as temperature goes!)
is caused by humans and not just a natural variation of the climate?”
Hmmm how would you be able to tell the difference? We can’t construct a bunch of ‘test Earth’ that we can use to run experiments. The next best thing we can do is make models. But they have (on this blog) been labelled as bad evidence (unless they show no warming of course )
Jonathan Wilkes says
“We can’t construct a bunch of ‘test Earth’ ”
Yes this is the sort of answer we get from the AGW proponents, which would be fine as far as I’m concerned, if it be left just as a theorethical exercise.
What worries me is the insistence that we “DO” something about it! even though there is no proof or evidence!
NT; I wonder what evidence would change your mind that CO2 is going to cause AGW. As a lawyer, I can tell you that the AGW case would have been thrown out of court a long time ago.
Continuing the ENSO connection, this paper seems to be to the point;
Nt all I’m saying is we are not seeing anything that hasn’t been seen before.
The trouble is you cannot prove the co2 enhancement case and let’s at least be HONEST we Aussies can’t make a scrap of difference.
We must do what humans have always done and that is clever adaptation.
We must spend our dollars as cleverly as we can and not waste it on this silly folly of trying to change the climate.
I honestly can’t understand anyone not cringing with embarrassment when we hear our PM claim that an increase of .01% of co2 will cause droughts, damage the Barrier reef and finish Kakadu.
This is the limit of absurdity when we produce just 1% of the planet’s GHG’s and China and India are giving the world the two fingered salute.
Of course the evidence doesn’t back up the co2 link quite the reverse, Spencer’s team findings etc.
“pruduced by the University of queensland has shown a cuasul link between vast land clearing and an increase in surface tempretures int eh basin of up to 2 deg C, worse than climate change”
Climate change is just starting.
Cohenite, I don’t think it’s wise to compare Law with science. The thing with science is that you can keep testing it, there’s no court to be thrown out of.
Jan Pompe says
SJT” “Climate change is just starting.”
Climate change has been happening on earth for 4.5 billion (give or take a billion ) years I don’t think it’s going to stop any times soon.
That is quite incorrect NT; law is continually changing, it is never static; how could it be when it is a perpetual attempt to improve the human condition; it can never stop because perfection and utopia is unobtainable, if for no other reason then because there are always at least 2 points of view. So too science; which should be concerned with improving human understanding; a process which will never end because finality of understanding is never obtainable, if for no other reason then there will always be at least 2 levels of understanding; the self and the other. Just as many laws over the years have been superseded and lost, so have many ‘sciences’; phrenology, Lamarckism; likewise, laws can reemerge, and so can discarded science; genetic manipulation techniques may yet vindicate Lamarck. AGW is an attempt to give legal force to a scientific perspective; the scientific perspective is to do with our immediate physical reality, and is cutting edge; which is why I am optimistic that some serendipity may come out of the current contortions; but make no mistake both law and science are interrelated in form and function.
This is appalling. The usual sceptic technique of leaving information out.
While there is nothing wrong with some things that Franks has said – it’s what he has not told the Australian public that’s disturbing. As well as his conclusions.
He has totally ignored much recent published work by many researchers on the southern annular mode (an Antarctic oscillation affected by both greenhouse and depeletion of stratospheric ozone), movement in the sub-tropical ridge, warming in the Indian Ocean, decrease in the Walker circulation, changes in the super-gyre, and east Australian current. A warming Tasman Sea.
Nor we do we see any discussion on snow depth and the effect of temperature and rainfall.
No discussion that temperature has been analysed over the major droughts this century and found to be much higher in the recent drought years. No discussion of the effect of these higher temperatures on vapour transport within soils or the effect of greater evaporative demand on trees and hydrology.
No discussion of any changes in the form of decadal oceanic variability.
And to the isuse orf El Nino itself ! No discussion on the possibility that the warming of the tropical central Pacific (Niño4 region), not necessarily related to a trend in ENSO but simply the global warming of the cean, together with the rises of MSLP above SEA have contributed to the autumn rainfall decline.
Readers would be well advised to realise the hand of the organised sceptic movement at work and read for themselves the latest science journal publications by CSIRO and the Bureau of Meteorology.
Indeed if climate change is having some impact it will do it over the top of existing variation like El Nino and La Nina and decadal influences. And it seems on balance that we have a bit of both.
It’s not a question of polarising the debate by stating that “CO2 did not not cause this drought” (which incidentally dates back to 1996) – it’ a question of whether there is a plausible argument for some anthropogenic influence.
Not to inform the Australian public of the full picture is reckless.
If he disagrees with that research he should formally address it a much has been published in the last few years including 2008.
Franks appears to be happy to be identified with many high profile sceptics in the infamous Open Letter to the Secretary-General of the United Nations decrying global warming research.
Plus happy for a guest spot doing a Lavoisier lecture.
Wake up – just part of the organised campaign -William, John, Bob and Stewart all popping up in op-eds in a very short period. How coincidental.
Alan Siddons says
“When soil contains high moisture content, much of the sun’s energy is used in evaporation. Consequently, there is limited heating of the surface. When soil moisture content is low (as occurs during drought) nearly all of that energy is converted into heating the surface, and air temperatures rise significantly. Consequently, higher temperatures are due to the lack of evaporation, not a cause of significantly higher evaporation.”
This echoes what I posted earlier: “The high specific heat of water means that it takes more energy to raise its temperature than that required for most other substances.”
When water is part of the local environment, temperatures will tend to moderate since much of the available thermal energy will go into heating the water, which is difficult. So the air is cooler as a result. Water vapor in the air is a RESPONSE to a high level of incoming energy, not a self-standing “greenhouse enhancement” that serves to raise the environment’s temperature. Water vapor is the opposite of a “greenhouse gas” because its presence LOWERS the environment’s temperature while thermal energy is coming in, the benefit being that it helps sustain an existing temperature while energy is going out. So something’s lost and something’s gained, a zero sum dynamic exactly as the conservation of energy law would imply.
Dump water vapor into the atmosphere of Mars. It will either freeze to the ground instantly or be convectively transported to the poles and THEN freeze out of the air. You wouldn’t have added a single degree to that planet.
“When water is part of the local environment, temperatures will tend to moderate since much of the available thermal energy will go into heating the water, which is difficult. So the air is cooler as a result. Water vapor in the air is a RESPONSE to a high level of incoming energy, not a self-standing “greenhouse enhancement” that serves to raise the environment’s temperature. Water vapor is the opposite of a “greenhouse gas” because its presence LOWERS the environment’s temperature while thermal energy is coming in, the benefit being that it helps sustain an existing temperature while energy is going out. So something’s lost and something’s gained, a zero sum dynamic exactly as the conservation of energy law would imply.”
“Climate change has been happening on earth for 4.5 billion (give or take a billion ) years I don’t think it’s going to stop any times soon.”
You know exactly what I meant.
Malcolm Hill says
That post of yours regarding the similarities between science and the law is excellent.
There is absolutely no reason why there cant be openess and transparency in science.
Law isnt the only example BTW.
Thanks Malcolm; as I tell my clients; it’s going to cost you this much, this what I’m going to do, this is why I’m going to do it, and this is what should happen because when I did this before that’s what happened; pity AGW exponents can’t do the same.
luke; you couldn’t resist the little jab ad homing Stewart at the end; and you coveniently ignore the body of work which allocates natural ocean circulation as the cause for the effects you describe; for instance, the Meyers and Wijffels papers on the 1976 event, McPhaden and Zhang and the Hazeleger paper I referred NT to above; the latter paper gets ignored because it uses GCM’s to ascertain whether CO2 is responsible for the effects you describe and conludes that it isn’t. Franks admits CO2 absorbs, but that its effect is limited; that really is the nub of the dispute; you guys simply can’t accept that CO2 can’t do the job; and of course H2O can’t either.
Wasn’t an ad hom. Just the facts. And very relevant.
His behaviour is shoddy. Just another anti-greenhouse theorist. Let’s not pretend this guy is a kindly objective scientist. He has neglected the entire modern Australian literature in an op-ed piece supposedly written by an esteemed concerned academic. Pull that one without full disclosure and you get a kick up the bum.
Face it – just another Lavoisier sycophant on the campaign trail.
BTW don’t get going on McPhaden and Zhang – it’s one my favs too 🙂
I’ll give you one thing though – the sole Australian sceptic who has published something on climate. So there is one !!
” the system has been knocked out of balance and is now trying to find its new equilibrium and that will keep changing whilst we mess with it.”
Now I know who The Lorax is: He’s Professor Malcolm, from Jurassic Park.
It’s the chaos people. You mess with nature and the raptors will escape and then…
Cohenite, that’s not what I meant. I meant if this went to court, it would go once. The finding on that occassion would be used forever, you couldn’t test it again. Hence you desire to find it being “thrown out of court” because if it was, it couldn’t be tested again.
Why would you use legal procedure to test science? Science works fine with it’s own procedures.
” AGW is an attempt to give legal force to a scientific perspective;” – Bollocks. Science does not create any legal force, that’s the domain of politicians and Judges. You have bought into the stupid conspiracy theory of AGW.
Science and Law are different. Legal laws are created and constructed by humans, scientific laws aren’t, they are discovered.
And this “pity AGW exponents can’t do the same” Is hilarious! You want AGW exponents to predict the future?? And have you ever changed your billing?
“you guys simply can’t accept that CO2 can’t do the job; and of course H2O can’t either.” I wonder why, when you keep posting papers informing us that it can!
Cohenite you have just decided the Miskolczi is correct and the rest are wrong, why? Because it suits your paradigm. For you this AGW argument is entirely political, it’s a battle between Left and Right, and being a good young Capitalist you have decided that anything that impedes a Free Market must, by default, be wrong. Your skepticism is very hollow and selctive. Frank Stewarts even states there is a Greenhouse Effect and that this is cause by anthropogenic CO2, but you decide to ignore it… Nicely skeptical.
Just because you can find papers that dispute AGW, doesn’t mean that AGW has been refuted.
So what evidence would prove to you that AGW is real? What is this incontravetible signature. I understand it is tropospheric warming and stratospheric cooling, but you decided that that is not it. Apparently you are convinced by Chillingar. You know why? Becuase you want AGW to be untrue.
Nicholls (2004) showed quit simply that each successive drought was warmer than the last, thus exacerbating the impacts.
He notes: “The apparently inexorable warming from the mid-20th century has meant that each drought was warmer than the previous drought, both during the daytime and at night.”
Prof. Neville Nicholls is arguably Australia’s leading climatologist for the past couple of decades.
NT; do I do character analysis of you, luke and the other pot-pourri? And you continue to verbal me; I would accept tropospheric warming; stratospheric cooling is a bit more vexed, in that there are multiple natural reasons and non-CO2 factors to explain that; as I have said, what would it take for you to admit AGW is grossly overstated or not real?
I think you hav it the wrong way round. There are natural ways of getting a warm troposphere (e.g. increased solar luminosity), the cool stratosphere is only found in AGW models (that is climate models show a stratospheric cooling only in models with forcings due to increasing GHGs).
I suppose there would have be a demonstrable problem with the way IR is absorbed and energy re-emitted. Or perhaps a more advanced model that incorporates more detail (for example clou behaviour) tht shows that increasing CO2 makes more clouds which shade the Earth… No, I think it would have to be a fundamental change in the physics of the Greenhouse effect (like Mikolscki says), but oe that also supports the paleoclimate evidence from geology (Ice Ages, Hot House climates etc.). So if you could demonstrate that the optical density of the atmosphere has changed and can support paleoclimates, it would be a counter model.
Arrgh I have to finish my assignment!!
“There is absolutely no reason why there cant be openess and transparency in science. ”
That’s why they publish papers, for gods sake.
Come on Cohers – I’m not verballing you. We like you. If you weren’t here the anti-greenhouse theorist side would be buggered. Look on it as mutual education.
And moving right along.
New Scientist 6 Sept 2008 asks again “Did early humans change the climate and avert an ice age?”
Early rice farming and anomalous methane trends
William F. Ruddimana, Corresponding Author Contact Information, E-mail The Corresponding Author, Zhengtang Guob, Xin Zhoub, c, Hanbin Wud and Yanyan Yub, c
aDepartment of Environmental Sciences, Clark Hall, University of Virginia, Charlottesville, VA 22904 USA bInstitute of Geology and Geophysics, Chinese Academy of Sciences, P.O. Box 9825, Beijing 100029, China Graduate School of the Chinese Academy of Sciences, Beijing 100039, China dInstitute of Earth Environment, Chinese Academy of Sciences, P.O. Box 17, Xi’an 710075, China
Received 25 August 2007;
revised 3 March 2008;
accepted 12 March 2008.
Available online 11 June 2008
The anthropogenic explanation for the increase in atmospheric methane concentration during the last 5000 years requires large CH4 emissions from human activities beginning early in the Bronze Age. This paper presents a compilation of 311 archeological sites in rice-growing regions of China. The number of new sites between 6000 and 4000 years ago increased almost ten-fold compared with those during previous millennia. This early spread of rice production across most of the area in China where irrigated rice is grown today supports the hypothesis that early farming caused the anomalous methane reversal.
For an alternative take on Ruddimania;
Cohenite, they deal with different time periods.
luke; do the math; Sage’s study shows that human civilization got a kick along due to a natural increase in CO2 from 200ppm to 270ppm; the AGW period proper allegedly kicks off due to a rapid post-IR spurt in CO2 from a base of 280ppm; so Ruddiman’s thesis about anthropogenic GHG production is predicated on a 10ppm increase over, what, say 5000 years?
Ruddiman is definitely on my shortlist for the 10 worst pro-AGW papers.
Going back to your, partially justified, concerns about SST derived droughts, here are a few more papers which argue that the connection is entirely natural;
Also of interest is the Dai, trenberth and Qian piece: “A Global Dataset of Palmer Drought Severity Index for 1870-2002: Relationship with Soil Moisture and Effects of Surface Warming.” They note:
“An empirical orthoganol function (EOF) analysis of the PDSI reveals a fairly linear trend resulting from trends in precipitation and surface temperature and an El Nino Southern Oscillation (ENSO)-induced mode of mostly interannual variations as the two leading patterns. The global very dry areas, defined as PDSI < -3.0, have more than doubled since the 1970’s, with a large jump in the early 1980’s due to an ENSO-induced precipitation decrease and subsequent expansion primarily due to surface warming,”
Malcolm hill says
There is absolutely no reason why there cant be openess and transparency in science. ”
That’s why they publish papers, for gods sake.”
Only after they have gone through a sieve, which is not transparent.
At least with law anyone can place a case on the counter, and have it heard, providing the grounds are legit.
Or to quote Richard Horton of the Lancet
“—- the system of peer review is biased, unjust, unaccountable, incomplete, easily fixed, often insulting, usually ignorant, occasionally foolish, and frequently wrong.”
Thats a pretty good system to be basing a complete upheavel of our economy upon.
The white coats and their camp followers, like SJT are beyond belief
Ruddiman – yes I know it’s controversial – but this is new – Ruddiman II see the methane story.
“ENSO-induced precipitation decrease and subsequent expansion primarily due to surface warming” errr – and that doesn’t go ding a ding for you.
Incidentally – some subtle stuff Cohers – maybe El Nino hasn’t changed but the mean state of the Pacific/Walker circulation has?? – see Smith and Power paper.
And maybe the old quasi-decadal behaviour is changing too (see Meinke et al paper)
Ping me if you want them.
Thanks for Herweijer et al.
OK Cohers – following on and given your pores are open – serious check this out dude.
And following on some more from Richard Ordway
What peer-reviewed references are there for global warming causing drought in continental interiors and violent weather on coastlines?
Alley, R. B, J. Marotzke, W. D. Nordhaus, J. T. Overpeck, D. M. Peteet, R. A. Pielke Jr., R. T. Pierrehumbert, P. B. Rhines, T. F. Stocker, L. D. Talley, and J. M. Wallace, 2003. Abrupt climate change, Science, 299, 2005-2010.
Cole, J.E., J.T. Overpeck and E.R. Cook, 2002. Multiyear La NiÃ±a events and persistent drought in the contiguous United States. Geophys. Res. Lett., 29, 10.1029/2001GL013561.
Dai, A., K. E. Trenberth and T. R. Karl 1998: Global variations in droughts and wet spells: 1900â??1995. Geophys. Res. Lttrs., 25, 3367â??3370.
Fye, F. K., D. W. Stahle and E. R. Cook, 2003: Paleoclimatic analogs to Twentieth-Century moisture regimes across the United States. Bull. Amer. Meteor. Soc., 84, 901-909.
Giannini, A., R. Saravanan, and P. Chang, 2003. Oceanic forcing of Sahel rainfall on interannual to interdecadal time scales. Science, 302, 1027-1030.
Haug, G. H., D. Gunther, L. C. Peterson, D. M. Sigman, K. A. Hughen, B. Aeschlimann, 2003: Climate and the collapse of the Maya civilization. Science, 299, 1731-1735.
Hoerling, M., and A. Kumar, 2003: The perfect ocean for drought. Science, 299, 691-694.
Hunt, B. G., and T. I. Elliott, 2002: Mexican megadrought. Clim. Dyn., 20, 1-12.
IPCC (Intergovernmental Panel on Climate Change), Climate Change 2001. The scientific basis. Eds. J. T. Houghton, et al. Cambridge University Press, Cambridge, U.K. 881pp.
Laird K.R., S.C. Fritz, K.A. Maasch and B.F. Cumming, 1996. Greater drought intensity and frequencybefore A.D. 1200 in the northern High Plains, U.S.A. Nature, 384, 552-554.
Nicholson, S. E., B. Some, and B. Kone, 2000. An analysis of recent rainfall conditions in West Africa, including the rainy seasons of the 1997 El NiÃ±o and the 1998 La NiÃ±a years, J. Clim., 13, 2628-2640.
National Research Council, 2002. Abrupt Climate Change: Inevitable Surprises, 182 pp., NationalAcademy Press, Washington, D.C.
Stahle, D.W., E.R. Cook, M.K. Cleaveland, D. Therrell, D. Meko, H.D. Grissino-Mayer, E. Watson, and B.H. Luckman, 2000: Tree-ring data document 16thcentury megadrought over North America, EOS, Transactions, American Geophysical Union, 81 (12), 121,125.
Stine, S., 1994. Extreme and persistent drought in California and Patagonia during mediaeval time. Nature, 369, 546-549.
Trenberth, K. E., 1998: Atmospheric moisture residence times and cycling: Implications for rainfall rates with climate change. Climatic Change, 39, 667â??694.
Trenberth, K. E., and C. J. Guillemot, 1996: Physical processes involved in the 1988 drought and 1993 floods in North America. J. Climate, 9, 1288â??1298.
Trenberth, K. E., A. Dai, R. M. Rasmussen and D. B. Parsons, 2003: The changing character of precipitation. Bull. Amer. Meteor. Soc., 84, 1205â??1217.
Trenberth, K., J. Overpeck and S. Solomon, 2004: Exploring drought and its implications for the future. Eos, 85, No. 3, 20 Jan. 2004, p27.
Verschuren, D., K.R. Laird, and B.F. Cumming, 2000. Rainfall and drought in equatorial east Africa during the past 1,100 years, Nature, 403, 410-414.
Woodhouse C.A and J.T. Overpeck, 1998: 2000 years of drought variability in the central United StatesBull. Amer. Meteor. Soc., 79, 2693-2714.
I assume you mean me Cohenite? Contrary to popular belief Luke and I are different…
Yeah you could be right.
NT; if you want an interesting take on stratospheric cooling you should read Spencer and Christy’s rebuttal of Fu’s paper;
luke; you had your chance to nominate your best AGW papers; the Vecchi effort should have been on your list; as far as I can gather they make a case that AGW mimics natural ENSO effects but has different mechanisms and will increase the frequency and extent of El Nino; since we have entered another PDO -ve phase with SOI in the +ve the next year should be interesting in respect of both solar and ENSO patterns. The good news from Vecchi is that if they are right, the frequency and intensity of hurricanes will be reduced.
No I was just supplied regional papers as I said – hadn’t even turned my hand to the main game yet – coz there’s so many. If that’s all you read into Vecchi I give up ! These are massive effects given AGW is just getting going.
But on historical records, La Nina in an PDO cool phase should be very good news for Australia. Should be. Basically La Nina and cool IPO analogue years are very wet. El Nino and cool IPO phase is a bit less drought overall – not much – but bad news is Murray catchments are worst years so say the analogues. Even SOI neutral with cool IPO is wet for MDB on analogues.
But of course we’ll have to see how SAM and STR pan out eh ? And a changed Walker circulation too … hmmmm
Of course as soon as it rains all the sceptics will laugh. But it’s just a single datum point on the big trend curve. Be good for all if it did rain heaps though. A circuit breaker is sorely needed.
Louis Hissink says
Oh Good Grief,
Peer reviewed papers at 10 paces!
louis; every time luke throws papers at me, there are more candidates for a worst list; I must say though, I feel like Wilson Mizner did when he was working at Warner Brothers.
“Nationally, 65.6% of agricultural businesses reported that they considered the climate affecting their holding has changed and 62.4% reported that the perceived change in climate had an impact on their holding. Approximately half (49.5%) of agricultural businesses reported a change in the management practices on their holding in response to perceived changes in climate”
The discussion on ABC rural radio yesterday mentioned the above paradigm
shift in attitudes behind the farm gate. Aparently some hard core sceptics need another decade or two of drought to be convinced climate change has occurred.
Flying from Canberra to Hobart today, I had a good view of how the NSW region beyond the ACT is still suffering compared to further south.
It was also a good chance to check on some major resevoirs along the way after “substantial” winter rains, Burrenjuck, Tumut, Hume, Eildon etc all need a little topping up before the summer.
BTW Lake George in NSW is bone dry and the Great Lake in Tassie looks sad
Louis Hissink says
Climate always changes, so to annouce that it had occurred is to indicate that it has stopped.
“lying from Canberra to Hobart today, I had a good view of how the NSW region beyond the ACT is still suffering compared to further south.”
And I have only seen Lake George wet once since 1959.
Good thing you are not flying in straw constructed flying vehicles.
Several interesting quotes from one of El Luko dipstick’s BoM-a-bubble sprays above:
“Indeed if climate change is having some impact it will do it over the top of existing variation like El Nino and La Nina and decadal influences. And it seems on balance that we have a bit of both.”
This is actual progress: an admission (all very guarded and quite coy) that the empirical data is proving somewhat difficult to fit into hypothesis.
But then, of course:
“Not to inform the Australian public of the full picture is reckless.”
Including the first quoted comment ?
Louis; a straw man in a straw plane?
Ian; this idea that AGW is temporarily overcome by natural process but still chugs along and will reappear with a vengence is the subject of the Keenlyside paper;
luke’s Vecchi paper which he links to above does something similar by asserting that AGW effects mimic ENSO process but have different mechanisms as deduced by the GCM’s. The problem with this was exposed by lucia when she removed the ENSO effect from post 1998 temperature data;
With ENSO removed you would expect the AGW factor to keep temperatures going up; but temps went down. This is a remarkable result; how to justify AGW then, when natural process defeats it as Keenlyside asserts, and when the natural process is removed there is no AGW effect in any event.
“This is actual progress: an admission (all very guarded and quite coy) that the empirical data is proving somewhat difficult to fit into hypothesis.”
Nope – have always said change would be mixed with existing variability – like for years dude! What would you expect to see?
If one did a thought experiment as to what the AGW signal might look like – I think you could easily imagine a blurry signal emerging from the fog of pre-existing climate variability – interannual and decadal.
There would not be a cinching argument as to a 100% attribution to AGW forces but evidence would suggest anthropogenic factors starting to move phenomena around. An added factor.
And these influences appear to affect more than the MDB – all of Australia and probably the southern hemisphere.
If anything I’m downplaying the “for” case.
Of course for you guys to understand that you’d have to do some reading and open the pores. (see my papers selection in comments in Cohenite’s 10 sexist AGW papers thread below)
Cohenite – are temperatures all you can think about? Global thermodynamics arguments backed up with observed data and explained by modelling Cohenite.
AGW simply modifying the base state over which ENSO works.
Your issue is that you don’t a have a system understanding of any of this. You’re looking at the issue with lawyer’s linear regression eyes.
The reality that you have major changes in SAM, STR, Indian Ocean, Tasman Sea, EAC and Walker circulation should be at least making you pause for some reflection?
Slide 13 here http://www.clivar.org/organization/pacific/meetings/presentations/SPower.ppt
Page 1 here is the systems intercation you are dealing with http://www.bom.gov.au/bmrc/pubs/researchletter/reslett_06.pdf
and STR discussed in http://www.bom.gov.au/bmrc/clfor/cfstaff/matw/abstracts/Timbaletal08.submitted.pdf
luke; the Sun Downward irradiance paper seems to contradict Philpona in that it doesn’t distinguish between solar and GHG DLW; both this paper and the Timbal and Murphy paper, allocating the cause of the statistically variant autumn rain in SEA to MSLP changes, use parameterization validation which is open to the alternative interpretation of Spencer like stochastic non-causal relationships between the changing factors. As usual, I can’t see a basis here, and I don’t have the time – my lawyer linear sight is chasing the buck; and what’s this left-field sexism nonsense? – to read all your links, for your support of an AGW signature in climate events which are still within natural parameters.
Yeah, plenty of straw in the heads of the anti AGW camp too
“The most commonly reported perceived change in climate affecting the holding was a change in rainfall patterns (92.1%), followed by more extreme weather events (74.2%) and warmer temperatures (49.6%)”.
cohenite; for your info, truth in practice does not rely on blogs or your hand picked papers
you’re fucking kidding me ! “parameterization validation” !!
mate you’re so far into the dark side shit you can’t see daylight
All this stuff going on – add it all up – and you have “some other” explanation to dream up for all of it. Coz you don’t want to see basically.
there is NOTHING that science can give you except a 50 year time trend of the effects. So really you might as well give it away now. Just accept you don’t and will never will be presented with any evidence you’d accept and be happy in that.
There’ll always be an “alternative” explanation in your mind.
For our man on the spot Louis
A little potted climate history “The sedimentary record from Lake George provides the longest relatively continuous Quaternary continental sequence yet available from Australia, and may record one of the longest Upper Cainozoic lacustrine records in the world”
that would be the night time downwelling radiation too would it 🙂
With the Great Lake 16 meters down from the wall there is a plenty of ground exposed between old boat ramps and the current level but this is an artificial hydro power storage area and the issue is complex considering the Poatina power station drain underneath. There are a lot of other natural lakes and lagoons in Tasmania’s Central Highlands too
“BRIAN Davis has been fishing at Arthurs Lake for more than 40 years and, in his opinion, the current level of the water is as low as he has ever seen it”.
Jennifer: Re the above local story; when it comes to scraping your tinny bum on the rocky bottom you can’t fool al of the people all of the time.
Louis Hissink says
A Wikipedia reference? Sure you can come up with something a bit more reliable than that?
Louis Hissink says
It is more likely that it’s our continued extraction of ground water that is the problem, as put by Lance Endersbee.
Whether you like it or not Gavin comparing the last 50 years with the first 50years of the 20th century shows that rainfall in virtually every state of Australia improved a lot or marginally improved from 1950 to 2000.
Only the SW of WA had a fall in rainfall in the latter half, virtually every state shows an improvement boosted by the cool phase PDO 1945 to 1978.
Tasmania overall shows a slight improvement over this period.
In my area Mildura ( Vic) according to BOM the period 1889 to 1946 average R/fall was 268mm Temp average Min 10.4c Max 24.5c then 1946 to 2004 average rainfall 283mm Temp average Min 10.3c Max average max 23.7c.
Forget about reams of non factual fantasies and stick to the facts and the truth.
Louis: “It is more likely…”
You are just guessing and I bet you did not read up on those links I gave before firing off blanks again. I see the southern states as one climate zone with some brine through the middle. What applies to the ACT also applies to Tasmania and Victoria.
Your ground water argument wont hold up in all places currently affected by drought. Climate change here as demonstrated by those links is essentially about lack of rain and hot winds over a long period
A caution re old measurements and “Extremes”
“While generally correct, the extreme values should be viewed with some caution. Extremes may have been recorded using non-standard equipment, particularly in the very early years of the Australian meteorological record; for example, pre-1910 temperature extremes. In addition, the extreme value may represent an erroneous measurement that escaped detection by the normal quality control processes”
So any excuse is good enough.
I’ve given you the facts showing actual records from the BOM.
By comparison look at the present day GISS manipulation and deception carried out by one of the high priests of AGW.
Earlier records have temp reductions and the later records are higher than the satellite record.
You either accept the past record as factual or you haven’t any scientific basis for your argument.
In other words your argument becomes anything you want it to be and in this case you want to show a higher temp and reduced rainfall.
Just a pity the facts and the truth don’t back you up.
You either accept the earlier record or your argument must have a base built on quicksand, no firm recordable base at all.
For something beyond A Bolt’s blog on Australia’s water resources we could start here
or we can understand the BoM data method
IMO though BoM won’t issue the same simple comparison above see Neville. For that we need to see BRS maps etc
gavin; it’s disconcerting that you should link to Torak and Nichols; BoM has been using their adjustment methodology for Australian temperature data for some time; it’s a disgrace, but Steve McIntyre has already extensively detailed the fiddling which goes on with the individual site data;
This analysis of Australian temp data collected from hundreds of sites is a 5-parter and liable to produce cynicism in all but the most one-eyed AGW supporter.
Cohenite I couldn’t agree more, if there is a bias why isn’t the more recent record hopelessly low because of the retirement of rural stations plus the the obvious city stations heat island effect?
There is a graph showing the temp heading north ( 1990 on) while the number of retired Rural stations head south as you’d expect.
Thousands of rural stations were retired after 1990 and I’m sure I saw this graph months ago at climateaudit, but I can’t find it at the moment.
Neville; there are some before and after composite Torak graphs here; when I look at BoM site data more often than not records finish at 1990 or 2000;
Thanks for that Cohenite it certainly has the strong smell of conmanship written all over it, thank heavens for top statisticians like Steve to do the hard work so that the layman can understand a bit more of the deception.
The above comments are typical of sour grapes in the anti AGW campaign. IMO they haven’t got a clue. By their very insincere focus on science, ie the method of recent data analysis with all that instrument history so conveniently forgotten we get a false impression they know it all.
I say most instruments and their readings of the day struggled to fall within +/- 2% despite our best efforts round that time
Brian said on C/A June 2nd, 2007 at 5:13 pm
“I worked for the Post Office in Australia for several years in the late fifties to the mid sixties and have first hand experience of weather observations done by Post Office staff in country areas. Most of them appeared to be more interested in the allowance for reading the weather rather than the accuracy of the observations, even if some of them could focus to take late night readings accurately. It was not unknown for the Postmaster at a small station to leave town for the weekend, after close of business on a Saturday, and leave the the ‘observations’ for the weekend with the telephone exchange operator to phone through to the MET Department at the appropriate time. More than one was caught out when a less than bright operator would ask the Met officer if he would like all the weekend reports as he/she had them there. I have been suspicious of small station weather observations ever since then”
Now that is about the same time I began a career in instrument technology. I also had a lot of contact with PMG personnel, technicians, Post Masters, linesmen and telephonists. I can say most were more pedantic about rules and regulations than any of us on here today, however they were involved as an organization with the daily weather reports but none of it was monitored in the same way our NATA registered enterprises were. Let’s add too in their favor, the internal grapevine was deadly on bad performance that could affect others in a rural community.
To sum up this lot based on years of trouble shooting measurement systems, I don’t care much for MWP, LIA or UHI in the greater scheme of things AGW.
Neville and cohenite truly belong with the bunch of amateurs on blogs!
I don’t understand your point at all gavin; I mean stripped of the sour grapes; the point is, pre-satellite data was extremely variable; given this, how can the major land temp collectors expect acceptance of trends they establish with, when it boils down to it, subjective adjustments to the raw data? As to the MWP; it existed; historical accounts prove that; the issue for AGW is whether the temps back then were such so as to disprove the AGW orthodoxy that 20thC temps and rates are exceptional; given that we agree about the unreliability of the record it seems odd that you can, on the one hand, dispute the accuracy of the record, while similtaneously using some arbitary adjustment to the record so that the record then proves AGW.
Bullsheeet Cohneite – you’d like them to use pre-1910 temperature data measured with Glaisher stand.and compare that to Stevenson screens – are you on drugs mate !?
I mean GISS smish – after all McIntyre’s grunging around how is our understanding of global temperature trends modified – errr – ummm – not all all – has the same wiggles as the satellite stuff (which is never questioned and it bloody well should be!?).
Cohenite – dude – what you need is to be forced to come up with a quality Australian met variable set given nothing other than the rawest of raw data and a pocket calculator. Then we’ll see how good you are. Toorak and Nicholls are very serious guys – if you go after them – better pack a bloody big knife aka Crocodile Dundee. Sure of your facts are you? That’s science sure too – not legal dodgy sure.
“pre-satellite data was extremely variable”
I really don’t get this love of satellite data. It has been highly variable and is not a direct measurement, but an interpolation of temperature. It’s one more tool in the warchest, but the reverence given it puzzles me.
Using Gavin’s point about the inaccuracy of the earlier temp record let’s ask the obvious, how do you know the earlier records are not hopelessly low.
In other words if you don’t accept the record you must rely on a particular prejudice or bias.
Once again let’s take the LIA and use the beloved Wiki as the reference.
The reduction in temp during that period is put at 1c to 1.5c, but since 1850 the planet has only recovered .7c of that reduction, so what is all the fuss about.
In the last 100 years the planet has been subjected to more solar radiation than at anytime in the last 10,400 years, surely that’s worth some part of that .7c as well?
What happens when Spencer’s team gradually gets full recognition for their work showing a negative feedback to extra co2, he predicts it may take 3years at least before the fraudsters are slowly exposed and throw in the towel.
In the last month even rags like the Age have allowed many serious scientists to write columns ( in the Business section) deriding AGW so it is slowly getting a run in the MSM.
The easy answer to all this of course is show us the positive feedback in the real atmosphere and show us that pesky hotspot.
Just a hint it hasn’t been done yet, I wonder why?
Cohenite: during the 60’s I was actually fully employed maintaining a range of imported instruments and sometimes building new ones including non linear devices but mostly at arm length from subs (sub standard reference) for temperature, humidity, pressure and flow. Where suitable calibration points like ice water and boiling point did not cover the range we improvised. Flash point of high grade transformer oil was one, liquid salt was another we used in the back yard lab.
Building up instrument standards outside a physics department is a very crafty business indeed and that’s why our outfit became trusted enough to be the first independent contactors in the local petro chemical industry with defacto international status in all manner of safety codes across companies in a complex.
In understanding trends, instrument accuracy is less important than reliability. The pattern of response has to be well known. Where as calibration is routine, the rest is an art with those most responsible hence the sort of BoM paper I linked to above. Smart Alecs fresh on the scene were my biggest problems. Finding indisputable proof for all ears and eyes of some pending event in time was another so I often had to act alone. In using initiative though we must never loose respect for our cobbers on the same job. That’s probably the hardest thing to maintain.
Neville after you have held a lot of thermometers and wondered how they could so differ the response is simple; go for all the ones that agree almost exactly and hope that is the majority from the bunch. Rejecting those you made in this first elimination process is particularly hard, but believe me fixing each one to conform later is the real chore. Have sympathy for those still struggling with old weather records at BOM hey because they probably never knew either the instrument maker nor the station minder.
“Once again let’s take the LIA and use the beloved Wiki as the reference.
The reduction in temp during that period is put at 1c to 1.5c”
Neville can you seriously imagine me trying do justice to your LIA armed only with a piece of wood as reference?
Thats the problem it’s not my LIA but everyones LIA and some very cold temps were endured by those people over five centuries with the Maunder and Dalton minimums being the coldest.
The reason given today for the LIA is Volcanic activity and low levels of solar radiation, remember the year without a summer referenced in literature around the world?
Once again our planet behaving oddly all on its Pat Malone without any help from humans at all.
“Once again our planet behaving oddly all on its Pat Malone without any help from humans at all.”
That’s why scientists conduct research. The result of the research is that much of this change is caused by us.
Now I’m starting to understand SJT ,so the LIA could be caused by humans afterall, well I never.
Of course that 1.5 metre increase in sea level 4,000 years ago could be caused by humans as well I suppose and the MWP gee you be should publish and be damned you’re sure to cause a sensation.
Gosh those silly loons who suggest that the LIA was caused by less solar radiation and volcanoes are real dullards because it COULD have been the human race that caused that 5 century misadventure.
Seriously I know that fanatical AGW urgers are at times extreme and delusional but this just about takes the cake.
“…As to the MWP; it existed; historical accounts prove that; the issue for AGW is whether the temps back then were such so as to disprove the AGW orthodoxy that 20thC temps and rates are exceptional…”
the MWP may or my not have existed, there is no definitive evidence either way. Again you make your choice based in supporting your paradigm.
Current evidence suggests it is warmer now, if you look at the material being exposed as Glaciers retreat in Canada, Alaska, the Alps, in Chile, New Zealand, typically this material is more than 3000 years old. This correpsonds with a warmer period.
Using the Milankovitch cycles as a guide the World should be slowly cooling. This led even led Arthur C Clarke (who was actually quite a good scientist) in the 1940s to declare we should burn coal to avoid the next ice age.
“Now I’m starting to understand SJT ,so the LIA could be caused by humans afterall, well I never.”
I think I said “this change”, the change that is happening now. You can chill out again.