Hi Jennifer,
2006 might be regarded as the year of climate change hysteria or perhaps the year where we had to get serious about attribution and what is and is not global warming.
Certainly one could not help but notice various bouts of unseasonal cold weather this year with frosts affecting fruit crops in Tasmania, juxtaposed with record high temperatures of late in western Queensland and Russia.
Following a press release from the World Meteorological Society , a regular commentator at this blog Sid Reynolds questioned whether the WMO has infra-red rose coloured glasses and can only see when warm records are broken, having previously listed an impressive slew of recent record breaking cold events.
THE STATISTICS OF EXTREMES
There is a perception that the climate change story selects record breaking events to suit its argument and ignores the cold extremes.
So how do we view extreme events. What’s fair and what’s not?
Certainly global warming theory does not say all weather will be suspended and all temperatures from here on, everywhere in the world, will be always warmer every moment of every day.
It does not say there will never ever be another cold spell – or even a record-breaking cold event.
Realclimate gives a cold overview on record breaking events: “In statistics, there is a large volume of literature on record-breaking behaviour, and statistically stationary systems will produce new record-breaking events from time to time. On the other hand, one would expect to see more new record-breaking events in a changing climate: when the mean temperature level rises new temperatures will surpass past record-highs”.
In short, the probability of cold extreme events should decrease over time.
REGIONAL COLD ANOMALIES
Inner continental Antarctica has cooled compared with a warming on the Antarctica peninsula and surrounding ocean.
The issue is discussed in ‘Interpretation of Recent Southern Hemisphere Climate Change’ by Thompson and Solomon
in Science 3 May 2002: 895, DOI: 10.1126/science.1069270 .
For a graphic view of that trend visit http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=17257.
HISTORIC COLD ANOMALIES
What about periodic cold extremes in recent centuries?
A very recent study published in Nature shows how changes in the thermohaline circulation may have contributed to the Little Ice Age .
From around 1200 until 1850, during which average temperatures across the Northern Hemisphere dipped by around 1 °C, the strength of the Gulf Stream also slackened by up to 10%, oceanographers report. The Gulf Stream, which is part of a vast pattern of currents nicknamed the ocean conveyor belt, carries warm surface waters from the tropical Atlantic northeastwards towards Europe. The reduced flow that occurred during medieval times would have transported less heat, contributing to the icy conditions that persisted until Victorian times.
ICE AGE
The ultimate cold event in an ice age. Despite popular opinion the current orbital positions make that unlikely for millennia.
THE PRESENT DAY
What studies of extremes do we have of our contemporary climate? Anthropogenic global warming theory would indicate a reduction in the frequency of cold events (but not disappearance).
Where we have decent long term data this is exactly what’s been happening !
From: Frich, P., Alexander, L.V., Della-Marta, P., Gleason, B., Haylock, M., Klein Tank, A.M.G. and Peterson, T. (2002). Observed coherent changes in climatic extremes during the second half of the twentieth century. Climate Research, 19, 193-212. http://www.int-res.com/articles/cr2002/19/c019p193.pdf
From: Changes in Climate Extremes Over the Australian Region and New Zealand During the Twentieth Century.
http://www.springerlink.com/content/j488604372402531/
There has been another, more recent study, involving much of east Asia and Australasia also showing statistically reduced frequency of cold extremes: http://www3.interscience.wiley.com/cgi-bin/abstract/110573943/ABSTRACT .
THE FUTURE
What do state of the art climate models say about cold air outbreaks (CAOs) in a greenhouse world?
Various studies indicate that although in many areas CAOs will decrease, in some areas there will be little change. How counterintuitive. So the global atmosphere is a complex thing – local circulation changes may override as basic aspects of greenhouse forcing for some areas:
http://ams.confex.com/ams/87ANNUAL/techprogram/paper_117372.htm
http://www3.interscience.wiley.com/cgi-bin/abstract/112510787
http://igloo.atmos.uiuc.edu/CAO/
http://www.int-res.com/articles/cr2002/19/c019p193.pdf
Interestingly, temperatures are expected to warm over the source regions of the CAOs and the coverage of snow and ice are projected to correspondingly decrease. However, the models do not necessarily project a corresponding decrease in the number of cold air outbreaks in all regions.
From: Changes in Cold air outbreak days from a GCM ensemble run. The behavior of extreme cold-air outbreaks in a greenhouse-warmed world. Stephen J. Vavrus, University of Wisconsin, Madison, WI; and J. E. Walsh, D. Portis, and W. L. Chapman. http://igloo.atmos.uiuc.edu/CAO/mrcm.freq.abs.diff.gif
IN CONCLUSION
In conclusion, one still should expect to see periodic cold extreme events in a greenhouse world.
Exact climatology will vary from place to place depending on circulation patterns.
A simplistic assumption that cold extremes will disappear and be replaced with only hot extremes is not what the science is showing. However, in general, a greenhouse world should have a higher frequency of heatwave events compared to the current climate, and a reduction in the frequency of cold extremes would be expected. This seems to be already occurring.
Regards, Luke.
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This contribution from Luke has been significantly shortened. In particular I have deleted some of the technical argument/abstracts from technical paper to make the post more readable. I hope some of this information finds its way into the thread through comment and discussion.
Jennifer Marohasy BSc PhD is a critical thinker with expertise in the scientific method.
Thanks Luke,
I found that very balanced and interesting. As an inveterate skeptic (in all things, especially those connected with news media or politics) I still suspect that volcanic activity has something to do with the warming of the Antarctic Peninsula. Heard Island may blow its top soon(ish), and the sea shall boil (har! har!) and greate monsters shall appear.
Nice work Luke.
Davey – it’s not only the Antartic Peninsula – it’s also Patagonia warming as well and the nearby ocean. They have dragged a temperature probe across the said volcanic area near the Peninsula and only noticed a very small local anomaly. The meteorology of the vortex and greenhouse warming are much more likely explanations IMHO. Inner Antarctica is effectively walled off. But the sub-Antarctic islands are certainly volcanically interesting nonetheless. Also very interesting ecologically. Researchers are also interested in species/elevation shifts on Heard Island as a sign of climate change.
Jen informs me that only 15% of we “dear readers” actually read web links (usually I’m one of them !).
So quite reasonably in the interests of brevity she has removed much of my precis discussion lifted from the papers and links. I think the arguments still stand and there is no over-simplification (especially if you read the links). Thanks muchly for the editing Teach !
Regardless of your cold soup I just took another big load of struggling garden to the dump (green recycle) so I can sleep a bit more easily over the fire season.
There is a gang over the road behind the house below falling their large eucalypts.
All the mature Hakeas up the side lane are dead or dying, Callistemons my side are shedding their foliage every where and if I had the energy I’d chop our the rest of my ground cover before the dusty dump closes for the year. The hidden barbeque area is next. The big man ferns just about had it too, one went in the wagon last week.
Sorry but we can’t entertain smokers outside now either, even the flattened cover over the lawn is volatile. Cool snaps we had sent the lot brittle.
Luke is certainly a great Apostle of the new pink/green religion.
Some comments on his posting.
There is a very subtle shift in perception here, and in the AGW community as a whole. As in para. 2, they find it hard to use the word ‘record’ when speaking of very cold weather events. So, as Luke does, they speak of ‘unseasonal cold weather ect.’ But, again as Luke does in the same para., they are quick to claim RECORD highs.
They still use a lot of scientific waffle to iron out historical events like the MWP and the LIA. Here and elsewhere Realclimate lacks integrity.
Note ‘Historic Cold Anomolies’ where name and content are carefully crafted to make all cold events to be only anomolies along the way to a hotter and hotter world.
I agree, Sid, there is a great deal of glib and dodgy word play, and partial truth, especially in media reports. But then, that has always been the style of journalists, salesmen, and politicians. They seek persuasion, rather than truth. I appreciated your family records of past droughts. I think local information is very rich. Any chance you will publish your family info?
These blokes could rationalise my old classic sports car’s speedo breaking down as a symptom of the fact it burns petrol.
I suppose they may be right. If I hadn’t burned any petrol, it wouldn’t have broken down, or at least, I wouldn’t have known it was broken down, if it was broken down.
Help! I think I’m catching Luke’s convoluted thinking techniques.
Merry Christmas.
That’s coz I was not sure if it was a record. I’m happy for it to be a record if it was a record. But the link (which only 15% of people look at) said “worst frost in more than 20 years “.
Had not discussed the MWP in this post. The LIA comment illustrates how an oceanic change can lead to a regional cooling effect. I think it is quite legitimate to debate how global or bi-hemispherical these events were. If you think the whole field of paleoclimate studies is waffle I don’t think we can ever know anything about past climates. I assume therefore you will have no further comment on ice cores or past climates as “it’s all waffle”.
The point of the post Sidnay, is to discuss what might expect from record events, can regional coolings occur and why, and what we might expect to occur in a greenhouse world. I suggest some of the answers are counterintuitive.
A fair bit of the above research has been done in the last few years.
Interesting in terms of religion Sid – it is only yourself that introduced the element of religion. Any reason perhaps? For the record I’m a devout atheist.
I await your Mooki percentile analysis.
Likewise I await your Murray headwaters analysis.
Only 15%? – I would have to see the data for that one….but 100% of me doesnt follow links (I mean, some people have to go out and earn a living so that you lot can sit around all day idley linking)
Seasons greetings you ungrateful bunch.
Sid, please explain how the MWP blows AGW theory out of the water. I’m all ears.
Merry Xmas Rog – happy nursery days – thank you for every severe upping, eye gouge and groin kick during 2006. I know I thoroughly deserved it.
Hasbeen you old codger – Yuletide greetings to you too !
Davey thank you for being kind and best wishes.
Gavin – thanks for being consistent and Merry Xmas.
Now back to biffo you bastards.
And of course a very Merry Xmas to Sid too (even if he is wrong). And I hope it rains for you in 2007.
In conclusion, measured climate records are short. Our own Central England Temperature series, for example, starts in 1659 – in the midst of the coldest part (1645-1715) of the generally cooler period known as the Little Ice Age (approx 1300 to 1850).
The LIA is also evident in 17th century Australia:
Five centuries of climate change in Australia: the view from underground. Pollack, H. N., Huang, S. and Smerdon, J. E. 2006.
J. Quaternary Sci., Vol. 21 pp. 701â??706.
ISSN 0267â??8179.
ABSTRACT: Fifty-seven borehole temperature profiles from across Australia are analysed to reconstruct a ground surface temperature history for the past five centuries. The five-hundred-year reconstruction is characterised by a temperature increase of approximately 0.5 K, with most of the warming occurring in the 19th and 20th centuries. The 17th century was the coolest interval of the five-century reconstruction. Comparison of the geothermal reconstruction to the Australian annual surface air temperature time series in their period of overlap shows excellent agreement. The full geothermal reconstruction also agrees well with the low-frequency component of dendroclimatic reconstructions from Tasmania and New Zealand. The warming of Australia over the past five centuries is only about half that experienced by the continents of the Northern Hemisphere in the same time interval.
The not too distant future climate could be cooler:
http://science.nasa.gov/headlines/y2006/10may_longrange.htm
Oh Biggsy, you’ve gone and spoilt it all. You aren’t that Biggsy with Brazilian connections are you?
Davey: I saw RB on several occasions and diamond cool Mrs B regularly enough to reckon PB is a poor con artist. Us of all people having cooler futures? Nah!
Paul – interesting new paper. What we have to sort through is whether we can attribute a solar mechanism or changes in the thermohaline and/or El Nino. What is causing what?
Thanks for Seasons Greetings Luke, and for the record I didn’t mean that all p’clim. studies are waffle. I believe that there should be more study into the mysteries of what drives our vibrant and everchanging climate. While our present knowledge is still limited, it is within Man’s or should I say Humankind’s, nature to keep seeking knowledge, and improving on it always. What I mean by waffle is when such studies are based on a preconceived ideological position, the pursuit of which will, in turn, produce the result required to support that ideology.
Thanks Davy, Yes there is some very interesting stuff amongst the family records, and I will try and share a bit as time permits. Am currently looking up a letter written from London during a particularly severe winter in the 1840’s, and I will post extracts.
And exactly, Rog. I for one, just don’t have the time to spend on this blog, as much as I’d like to; or to read and research matters.
And Nexus6, briefly. Plainly, without today’s science and technology, we should take into account, contempory writings, of which there are many, about past climatic and weather events.
Based on these historical records, one can only conclude, (as did climate science, generally, until about the mid 1990’s), that the MWP was warmer then today. In fact, about that time the MWP, was becoming an embarrassment to the AGW industry, who, through their flagship, the IPCC, were trying to promote their theory as ‘fact’ that the ‘sudden warming’ of the late 20th Cent. was ‘unprecented’. So, they decided to eliminate the MWP!… And, in short, did so!!.. If you look at the ‘Hockey Stick’ graph, you will see that the MWP, and also the LIA have been largely ‘ironed out’of existance!
A very Happy Chrissy to one and all. Especially to Jennifer, for making this excellent Blog available, and for trying to keep us all within the limits of civility!
Sid – AGW does not depend on whether the MWP or LIA was global, local, or as warm or warmer than today. If the MWP was as warm or warmer than today well the increasing CO2 will simply make it even warmer in the future than we now contemplate ! And indeed AGW does not just say EVERYTHING is CO2 driven – indeed climate is a function of solar input (primarily); CO2; volcanism emissions and anthropogenic aerosol pollution; land surface brightness (albedo) – tree clearing, tree expansion, desertification, breaking up of ice to expose darker seawater; and it now also appears – ozone holes and thermohaline circulations. i.e. there are a number of mechanisms at play – even simultaneously. The rapid warming in the last 30 years has no other driver that I can see other than CO2 increase – no change in solar output of note. And empirical evidence by satellite (spectral bands changing) and on the ground of the greenhouse effect using radiometers (Philipona) backs the theory up solidly.
If indeed the solar cycle theorists are correct and we’re about to enter in a solar cooling phase it doesn’t mean the extra CO2 would not have any effect. Would simply be not as warm as if solar output stayed as it is today. You can quite easily have both solar and CO2 forcing working as we do now – together. It doesn’t have to be one or the other !
I am working on the Murray percentile analysis !
And lastly the “even if he is wrong” quip was an attempt at humour.
I am glad Luke has got my mind right again. That Biggsy and his sunspots had me all of a doo-dah.
A pair of White Faced Herons is nesting twenty metres up in a red gum tree near my house. The male and female share sitting, ten hours on, ten hours off. They have just dropped the egg shells (lovely blue) on the grass below. They catch frogs (probably rare & endangered) in the pond. There seem to be more frogs this year than last, and bandicoots abound (ex-rare & endangered?). Is all this due to global warming, or sunspots, or my opening the deep-freeze door too often? Was it all the same back in the MWP and the LIA? Which is cause, and which effect, and what is spurious correlation? I seek clarification, before calling in a TV journalist.
Davey – look it’s quite simple – endangered species are well known to be correlated with the QBO (Quasi-biennial Oscillation) especially Quokkas and Quolls.
Your turn Biggsy – are recent events due to the GWFAB or the SWFF?
(P.S. Global Warming Favours Australian Batsmen & Shane Warne Fear Factor)
Regardless of local anomalies, the warming world is well documented despite all out attemps at discrediting NASA findings. There is no such “No cooling local anomalies allowed” thesis that I’m aware of. Nice try.
Jen, I am so, so sorry. Mark A. York came to your site because I referenced it in a comment on mine, and now you are cursed with his endless ramblings and twists on global warming. He does serve a purpose, though, which is to show the extremes of global warming worshippers.
Massive all time record snowstorm paralyses much of Colorado:
My sister and her husband,Tom, live, and farm in South Dakota and were to have Christmas with us here in Australia. My sister arrived earlier this month. Tom was to arrive tomorrow, but is still stuck at Denver International Airport, which has been shut down with massive snow cover.Denver received 25 inches of snow yesterday, an all time record snowfall for one day there. And it’s still snowing. Tom says that over 1,100 flight hav been cancelled at DIA, with all road traffic paralyzed as well, with more blizzard conditions forecast.
So looks as if Tom is stuck there, instead of spending Christmas with my sister, and all the family here.
Could this be yet another one of those ‘localised cold anomalies’ the AGW brigade talk about?
Well, back to ‘tending our stock by night’, and day, this Christmas.
Yep sure is – and we’re getting fewer of them says the data.
Show me the evidence that says we’re getting more.
That’s called “numbers” Sid !
I used to believe in global warming due to Co2 rise since records from Hawaii. However it seems Co2 can only account for a very small rise up 420ppm and none above this, since it is a very small component of greenhouse gases. Also from reading some serious papers by american meteorologists comments on recent data. It is extremely worrying to see public personalities jumping on the global warming with no serious long term statistical evidence (> 2000 years)whatsoever. One can only surmise that they want more “research funding”. They may find themselves in ackward position if the cooling global trend since 1998 continues (see NOAA site).
Well wingnut Woodt strikes again. You know I’m sorry to bug you good folks with facts, but I’m afraid they’re still on my side. Local increases in precipitation are predicted in the models. They’re perfectly aligned with the Warm World. I know this is tough for the mentally challenged to grasp but snow in Denver doesn’t disprove AGW. It proves it.
So does the lack of it in the Arctic and thus my novel Warm Front.
http://www.gather.com/viewArticle.jsp?articleId=281474976900570
And good work Luke. Keep at it.