CSIRO – climate variability caused drought, not climate change

While this is a bit dated, from late last year, given all the attention given to the floods in Queensland supposedly being caused by global warming aka climate change, this seemed relevant to review. h/t to reader Baa Humbug and Andrew Bolt

“Ongoing research is examining whether increased temperatures linked to climate change in the future will alter the frequency, intensity, and duration of drought. We are also investigating if the rising temperature due to climate change has played a part in the unprecedented low water storage level of the recent drought and how climate change will impact on climate variability.”

The study centred on the contribution to rainfall by naturally occurring events such as El Niño and La Niña, as well as a longer-lasting feature called the Interdecadal Pacific Oscillation (IPO), and how these events may be influenced by future climate change.

SEQ is one of the wetter regions in Australia due to its proximity to the world’s most intensive rainfall-band, located in the Western Pacific. The rain-band, which is powered by the warmest ocean surface temperature on the globe, moves eastward during El Nino tending to decrease SEQ rainfall. During La Nina, the rain-band moves westward leading to increased rainfall in SEQ. Many of the wettest years for the region occurred in La Nina years such as 1956, 1971, and 1974.

Much of the regional annual rainfall is recorded in summer. In recent decades, SEQ summer rainfall has been significantly reduced. Up until the drought breaking 2010 La Niña event, the SEQ water storage level dropped to below 20 per cent, the lowest level on record since data collection began in 1890.

The El Niño-La Niña relationship oscillates over several decades, in tandem with the IPO, which has a somewhat similar pattern to the El Niño-La Niña cycle but on a longer time scale.

“Since 1980, the IPO has been in a phase similar to El Niño – limiting the rainfall that La Niña brings to SEQ as a major rain-generating mechanism,” Dr Cai said.

“This is largely responsible for the recent drought.”

As of 2010, the IPO appears to be moving to a phase similar to La Niña.

Taking the average of results from a set of climate models is the most effective way of ‘distilling’ a climate change signal. The science team assessed the role of climate change by using the same 24 models used by the Intergovernmental Panel on Climate Change.

Their results show that the recent drought in SEQ is not consistent with climate change projected by the models.

Funded by the SEQ Urban Water Security Research Alliance, the study’s findings were published recently in the American Meteorological Society’s Journal of Climate.

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

Here’s the paper:

Cai, Wenju, Peter van Rensch, Tim Cowan, Arnold Sullivan, 2010: Asymmetry in ENSO Teleconnection with Regional Rainfall, Its Multidecadal Variability, and Impact. J. Climate, 23, 4944–4955.

doi: 10.1175/2010JCLI3501.1

Asymmetry in ENSO Teleconnection with Regional Rainfall, Its Multidecadal Variability, and Impact

Wenju Cai, Peter van Rensch, Tim Cowan, and Arnold Sullivan

CSIRO Marine and Atmospheric Research, Aspendale, Victoria, Australia

Abstract An asymmetry, and its multidecadal variability, in a rainfall teleconnection with the El Niño–Southern Oscillation (ENSO) are described. Further, the breakdown of this relationship since 1980 is offered as a cause for a rainfall reduction in an ENSO-affected region, southeast Queensland (SEQ). There, austral summer rainfall has been declining since around the 1980s, but the associated process is not understood.

It is demonstrated that the rainfall reduction is not simulated by the majority of current climate models forced with anthropogenic forcing factors. Examination shows that ENSO is a rainfall-generating mechanism for the region because of an asymmetry in its impact: the La Niña–rainfall relationship is statistically significant, as SEQ summer rainfall increases with La Niña amplitude; by contrast, the El Niño–induced rainfall reductions do not have a statistically significant relationship with El Niño amplitude. Since 1980, this asymmetry no longer operates, and La Niña events no longer induce a rainfall increase, leading to the observed SEQ rainfall reduction. A similar asymmetric rainfall teleconnection with ENSO Modoki exists and shares the same temporal evolutions.

This breakdown is caused by an eastward shift in the Walker circulation and the convection center near Australia’s east coast, in association with a post-1980 positive phase of the interdecadal Pacific oscillation (IPO). Such a breakdown occurred before 1950, indicating that multidecadal variability alone could potentially be responsible for the recent SEQ rainfall decline. An aggregation of outputs from climate models to distill the impact of climate change suggests that the asymmetry and the breakdown may not be generated by climate change, although most models do not perform well in simulating the ENSO–rainfall teleconnection over the SEQ region.

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38 thoughts on “CSIRO – climate variability caused drought, not climate change

  1. From the same orgainsation (but a little more recently)

    “Despite 2010 being a very warm year globally, the severity of the 2009-2010 northern winter and a wetter and cooler Australia in 2010 relative to the past few years have been misinterpreted by some to imply that climate change is not occurring,” Mr Hunt said.

    “Recent wet conditions in eastern Australia mainly reflect short-term climate variability and weather events, not longer-term climate change trends. Conclusions that climate is not changing are based on a misunderstanding of the roles of climatic change caused by increasing greenhouse gases and climatic variability due to natural processes in the climatic system.

    “These two components of the climate system interact continuously, sometimes enhancing and sometimes counteracting one another to either exacerbate or moderate climate extremes.”

    http://www.csiro.au/news/climate-is-warming-despite-ups-downs.html

  2. The opening statement in the press release is quite informative

    “We found that, unlike in South-West Western Australia, climate change plays little part in the SEQ rainfall reduction, but cannot be ruled out,” Dr Cai said.

    “unlike in South-Western Australia” – ie climate change DOES play a part there
    “cannot be ruled out” – ie uncertainty

  3. So, what they are saying is that climate changes on natural cyclic paths and this means that the weather changes from dry to wet. Well we all knew that. We all also know that this has been happening for 4.6Ba. and will continue so to do.

  4. Question ?
    how many “official” weather stations are there per square km in the world ?
    I notice that in a distance of 250 km in Europe 10 degrees C difference is not unusual, and rain, snow, wind, sun, clouds, all follow the temp. footsteps.

  5. The establishment will fight tooth and nail going forward, to convince us that AGW is real, so it will be a hard fight to recapture the minds of a deluded populace. Yet we have time on our side…natural variability rules!

  6. AGW/CC/CD is being driven really hard in the Australian MSM at the moment, with commenters talking about “CO2 blankets” etc, afterall, it will be the year of the Australian carbon tax fix, which Gillard took to the general election stating there would be no such tax (Well, I mean really, who believes politicians? It appears most chardonay drinking socialist Australians believed Gillrd and Brown). There are more column inches being devoted to AGW. Now, not only does the Gillard gubmint want a “price on carbon” it also wants a “flood levy”!

    WOW! Seems the only way to “fix” natural events is a tax. Will we have a wind tax? An earthquake tax? A bear, man, pig tax? Gillard, like Rudd, you will be a one term wonder.

  7. Australian Liebor, like the UK Liebor Party, believes that everything can be fixed by taxing it so they can continue their champagne lifestyles – and to get away with it, they have to keep the AGW/CC/GW/Whatever Disaster debate on the front pages so the gullible will continue to buy it…

  8. The climate scientists seem to be tippy toeing very gingerly towards the fact that there is a longer term cycle than the brief Le Nino / La Nina episodes.

    I forecast that they will eventually advise us of the 60 plus year chaotic cycles they were denying until very recently.
    Don’t be surprised when they make this starling relevation.
    But LO, it’s been sitting there, quietly sleeping in the middle of their data all along.
    Wonderful what a Cray computer or two can reveal.

    They may even amaze us with a lecture or two, explaining what H.E Hurst published about chaotic cycles and climate in 1951.
    Modern science is wonderful. Ain’t it?
    As my old English teacher used to say.

  9. Climate Change suggests that a desert becomes a tropical paradise, or vice versa. Ice bound regions could become temperate, and temporate tropical or polar. The geological record attests to this.

    On a fixed oriented earth with the only factors limited to solar radiation and/or CO2?

  10. “Their results show that the recent drought in SEQ is not consistent with climate change projected by the models.”

    Who’d have believed it – even the green socialist Csiro club realise the IPCC climate models are useless. Yet another example of a CAGW organisation moving away from ‘the message’ and starting to employ CYA tactics.

  11. “Louise says:
    January 21, 2011 at 2:12 am
    The opening statement in the press release is quite informative

    “We found that, unlike in South-West Western Australia, climate change plays little part in the SEQ rainfall reduction, but cannot be ruled out,” Dr Cai said.”

    South-West Australia is the only part of the continent that is dry. And since drought in Australia is by definition due to CAGW, thus climate change is active there. The rest of the continent is sopping wet. This is due to natural variability. Simple really.

  12. The stuff in the Australian MSM gets more and more unbelievable.
    The very cold winters in the northern hemisphere is being noted by commentators.
    The idea that the cold has been caused by rising temperatures has not been swallowed too well.

    An attempt was made by the green party to blame the very bad, widespread floods on global warming.
    That was shouted down by both major parties.
    It did not fly too well.
    There are too many ordinary members of the public with memories and family stories of bad floods going back at least to 1840.

    2011 is going to be an interesting year for Australian politics and for the climate debate, both here and overseas.
    I am always too optomistic, but I can’t help thinking that “the times, they are a changin’”.
    Hope so!

  13. Louise says:
    January 21, 2011 at 2:12 am

    The opening statement in the press release is quite informative

    The opening paragraph in Anthonys article is quite informative (to some) Louise.

    given all the attention given to the floods in Queensland supposedly being caused by global warming aka climate change, this seemed relevant to review.

    This is about the likes of David Karoly and Bob Brown who’ve linked the Qld floods to AGW. This is about the shameless opportunism of Karoly et al being called out by their very own alarmist organization (the formerly great) CSIRO.

    Geddit?

    p.s. Drought in WA caused by CO2 but floods in SEQ not caused by CO2. What? CO2 molecules are on holidays over in the west are they?
    AGW in the east should resume as soon as they come back from holidays lol

  14. Julia just cannot take a trick at the moment and things are only going to get worse. The State enquiry into the the Brisbane floods is set for a whitewash, I expect this will not happen. We will see a divided report from the State enquiry. We will see a more “engineering” based report from Brisbane Council which will be negative to the Government. All hell will break loose with class action court cases.
    Federal Government policy in regard to Victoria and the Murray Darling will be trashed and the Liberal opposition may just, once again, manage to turn victory into defeat.

  15. “Baa Humbug says:
    January 21, 2011 at 3:52 am”

    Bob Brown also attributes the Qld floods to digging coal out of the ground and shipping it to China.

    “Louis Hissink says:
    January 21, 2011 at 3:09 am

    On a fixed oriented earth with the only factors limited to solar radiation and/or CO2?”

    Fixed? Are you absolutely sure about that Louis because there is plenty of evidence which suggests you are very wrong.

  16. The tragic irony is that Climate Variability produced a man-made disaster – the unecessary flooding of Brisbane.

    This event also falsifies a critical aspect of the AGW hypothesis – mitigation will reduce the impact of climate extremes.

    Dams were built at huge cost to mitigate floods in SE Queensland – they failed to do so because their design and operation were flawed.

    Mitigation is a human construct and not a physical reality.

  17. This is all an effect of the lunar declinational tides in their 18.6 year pattern of changes.
    I forecast the weather based on a repeating cyclic pattern, the analog years for this year (2011) are 1956,1974, and 1992.

    From the article””Many of the wettest years for the region occurred in La Nina years such as 1956, 1971, and 1974.””

    So nothing to see here I guess, if some one from Australia could send me an FTTP site address where I could download all of the raw daily data from as many of the stations as possible from 1900 onward to present, I could produce a 10 year long forecast for you free of charge and available with in ~6 months or less.

    richard at aerology.com

    I would add an Australian page to my web site for your use, at my expense, just as I have now a forecast for the USA, for past three years and the next three in a daily map format.

  18. An attempt was made by the green party to blame the very bad, widespread floods on global warming.

    So why weren’t the greenies publicly urging the Qld. premier to release water from the dam at the specified 60% level, instead of letting it accumulate far beyond that? Their silence was complicit with her policy. They can’t now credibly blame the flooding they couldn’t foresee as a predictable consequence of GW.

  19. “Louise says”
    Louise, you are making a big deal out of the term climate change. Given the long period climate variations that made the MWP and LIA (and other warm and cold periods), there is natural variability that causes climate change, and we are clearly in a warm cycle. That gives no evidence that this is human caused or even human modified. The fact that weather patterns can change when we are at different parts of natural cycles is of no surprise. What precisely is your point?

  20. “Roger Knights says:
    January 21, 2011 at 5:22 am”

    Because before the rains and floods, Australia would have permanent dry, and water security was a priority (Hense all the de-sal plants being built in Aus).

  21. “Australian Liebor, like the UK Liebor Party, believes that everything can be fixed by taxing it”

    It is high time they put a tax on poverty and thus eliminate it. A tax on poverty will give people the incentive they need to be rich. This solution should be applied worldwide by the UN, to solve global poverty. The poorer you are, the more tax you should pay. Over time this will eliminate the poverty the same way carbon taxes will eliminate global warming.

  22. “Is it due to global warning?”

    Can this question ever be answered honestly by someone who has not completely lost all integrity and neglected all good scientific virtues?

  23. My dictionary defines ‘variable’ as ‘changeable’ and thus ‘variability’ (noun) as ‘change’. The same dictionary defines ‘change’ as to ‘undergo a variation’. Hence climate variability IS climate change! I’m reminded of Humpty Dumpty who made words mean whatever he wanted them to mean.

  24. Proof of man made climate change is like hunting elk.
    You can hunt elk even when there is no elk although you may not know there are no elk but you cannot shoot an elk, and eat an elk until you have actually found at least one. And if you shoot a rancher’s cow by mistake you still have not found an elk. Also don’t let the rancher or game warden catch you with an elk tag on a cow.

    Scientists have looked for man made climate change proof and so far have all the proof of the existence of big foot. It seems to me until absolute proof of the existence of disastrous climate change is found any change in the weather should not be first considered to be the result of climate change. That is like tagging the cow with an elk tag.

    I probably used the wrong animal, we know there are elk but and if no one had ever seen one before we would not know it existed until someone produced one and the species would not continue until all the conditions for that were met.

    In other words calling harsh weather the result of man made climate change does not make it so anymore than putting an elk tag on a cow meets the requirements of the elk license.

    We should be thankful for ranchers and game wardens that can identify mistakes in hunting. And for scientists who do the same in research and reporting.

  25. “Climate change” cannot be the “cause” of anything. A virtually meaningless and void concept such as “climate change” is not a tangible phenomenon, it is a human projection. The same goes for “climate variability”. This can never be the “cause” of anything, even “la Nina” or “el Nino” cannot be the “cause” of anything they happen to coïncide with. I appreciate that it is difficult to phrase meaningfull thesis relating to an ill defined concept such as “climate” which is an inherently variable concept but that is no excuse.

  26. David Stockwell at Niche Modeling evaluated CSIRO’s Drought Exceptional Circumstances Report:

    ABSTRACT
    This paper evaluates the reliability of modeling in the Drought Exceptional Circumstances Report (DECR) where global circulation (or climate) simulations were used to forecast future extremes of temperatures, rainfall and soil moisture. The DECR provided the Australian government with an assessment of the likely future change in the extent and frequency of drought resulting from anthropogenic global warming. Three specific and different statistical techniques show that the simulation of the occurrence of extreme high temperatures last century was adequate, but the simulation of the occurrence of extreme low rainfall was unacceptably poor. In particular, the simulations indicate that the measure of hydrological drought increased significantly last century, while the observations indicate a significant decrease. The main conclusion and purpose of the paper is to provide a case study showing the need for more rigorous and explicit validation of climate models if they are to advise government policy.

    Stockwell, David R.B., 2010. Critique of Drought Models in the Australian Drought Exceptional Circumstances Report (DECR), Energy & Environment, 21:5, 425-436, DOI:10.1260/0958-305X.21.5.425, Link:http://multi-science.metapress.com/content/L4870G0N8Q064377

    Stockwell lists further studies showing AGW is wanting.
    Discredited AGW

    My position is that the extreme claims of anthropogenic global warming are based on dodgy statistics. All of my publications discrediting extreme claims have been vindicated.

  27. Yes, but I distinctly remember a Senior Australian AGW official saying global warming is unequivocal, and Australia will get drier. Flannery said SE Qld will get drier, but like the weather they can just change their mind, but I do wish they would stop being so certain each time they change it.

  28. Of course the CSIRO had to say that. A couple of years ago they were saying that global warming would bring endless droughts.

  29. Thanks tty and Baa Humbug.

    They really must keep their story consistent.
    Otherwise, people start asking awkward questions.

  30. If global warming is going to be blamed for anything to do with the Queensland floods in 2011 then perhaps it should be blamed for the 2011 flood series being less extravagant than those of 1974. 1974 was toward the end of a period of cooling.

  31. The Period of “Climate Variability” (transition) can last as long as (or longer than) “Warm Climate”(MWP) and “Cold Climate”(LIA). The transition between “Warm” and “Cold” can be as disruptive (or more so) as the two ‘Titled’ phases themselves. Me thinks we be transitioning now.

    http://www.climate4you.com/ClimateAndHistory.htm

  32. Link to the CSIRO report:

    http://www.csiro.au/news/SEQ-Drought.html

    There is a sentence that is remarkable:

    “We found that, unlike in South-West Western Australia, climate change plays little part in the SEQ rainfall reduction, but cannot be ruled out,” Dr Cai said

    So in South-Western Australia the drought IS probably related to Global Warming. And last year was the region worst drought on on record:

    “Driest year on record for southwest WA”

    http://www.bom.gov.au/climate/drought/drought.shtml

    On the other side, the recent Queensland floods are almost certain the result of a strong La Niña PLUS a warming trend in Sea Surface Temperatures:

    “Annual Australian Climate Statement 2010″

    http://www.bom.gov.au/announcements/media_releases/climate/change/20110105.shtml

    See the last graph: 2010 Australian SST in 2010 were the warmest on record. With record warm water, there is a lot of evaporation. If the conditions are right (i.e. strong La Niña) this extra water vapor will cause record or near-record flooding.

  33. ““We found that, unlike in South-West Western Australia, climate change plays little part in the SEQ rainfall reduction, but cannot be ruled out,” Dr Cai said”

    I also found this statment to be rather odd.

    Finally! Some summer temperatures in Sydney, Australia. 35c in the city, about 36c out in the west. Australia Day is predicted to be between 36-4c in the West. All being blown out of all proportion in the MSM, and about 5 weeks of “summer” to go.

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