Wednesday
Sep252013
by 
Bishop Hill
Bishop Hill Two years after
Sep 25, 2013 Climate: Surface With the pause in global warming all the rage, it's fun to recall what BBC journalists were being taught just a couple of years ago.
;)
Reader Comments (32)
Given that the satellite data sets are essentially flat as from 1979 through to around the Super El Nino of 1998, perhaps we should be asking was there in truth any warming between 1979 and prior to the Super El Nino of 1998?
Was the claimed warming during this period 9as seen in the land based thermomemter data sets) just simply an artefact of UHI, poor siting issues, poor screen maintenance, station drop outs and/or the effects of adjustments/homogenisation of the raw data the need for which is moot?
Is the reality that there was some warming coming out of the cold 50s and 60s (the globe having cooled since the 1940s) but that warming essentially ceased by the end of the 1970s whereafter the only warming that has taken place is that associated with a one off and isolated Super El Nino event?
Newsnight last night was very interesting - the openly sceptical tone is starting to surface now even there. Failure to warm is wot done it.
Have there been pauses in the past?
Dave: "Have there been pauses in the past?"
Presumably the answer is "not since records began". Which could be 1979, 1909, 1850 etc
Oh, and not while CO2 is at an "historical high"....since records began in 1950....etc etc
See, depends how you spin it. Just like Richard Black. Remind me someone what his educational background is?
Nice to see a BBC (ex) environment correspondent showing a deep understanding and utmost impartiality.
A bit like Roger Harrabin. ho ho ho
I personally doubt the BBC has really changed..
Anyone got an answer without such anger mixed in with it. Thanks
Dave - someone posted this graph a few weeks ago which does suggest the AMO cycle has a global effect on mean temperatures and not just regional.
Hadcrut4 Global (detrended) and AMO
I'd say the pauses are cyclical, and there have been many pauses in the past. It really is staggering that the climate alarmists managed to convince so many scientists, politicians and journalists that the late 20th century warming was entirely and solely due to CO2, when a 1 or 2% decrease in cloud cover could easily explain the higher temperatures. The only question is how much of the trend is from 1880 to now is due to the long slow thaw from the LIA, and how much is due to dodgy station selection, and widespread fraudulent adjustments for UHI and TOBS etc.
Thanks lapogus
Dave, I think the answer to your question is "we don't know." The further back you go in temperature records, the less reliable they become. In addition, locations of measurement instruments changed, the instruments themselves changed etc. So we can't compare apples with apples very far back at all.
Certainly, given that modern climate science is obsessed with fractions of a degree, even the most recent figures are hotly contested.
On the other hand, the CET record might indicate localised periods of stable climate - you would have to ask an expert like Tony Brown about that. But on a global basis, anything back more than a century is practically impossible to verify to the degree of accuracy that is required to give a meaningful answer.
To Dave @10:29 AM:
Read this.
richard verney
A very perceptive comment and especially so in the light of yesterday's remarks about the use of anomalies vs actual temps.
The graph shown above is better seen at Greenie Watch. Note the explanation of why it looks like it does. It's all a matter of presentation.
Just out of curiosity I have been playing around for the last hour (my abilities with Excel being only marginally better than Phil Jones'!) and produced something quite different.
I took the most recent version of UAH MSU global monthly lower troposphere temperature anomalies since December 1978 from Climate4You (simply because they were the first ones I saw), added an arbitrary figure for the average temperature of the earth (14.5C, which I think is generally accepted as a good approximation) and then transferred the data to an Excel graph.
I cheated by making the scale -10 to +30, which is (in my view) not a bad approximation of the annual range of temperatures in a temperate climate and ended up with a wiggly line which will scare no-one! In fact as we all know the day-to-day variation can be 200 times the monthly anomaly and where I am, last week's range (9.3 to 23.4) was almost exactly 100 times the UAH trend figure (0.14).
What are we supposed to be panicking about?
Dave
I'm at a loss to understand your question about "previous pauses".
Climate is not and never has been constant. I assume you are aware of the Minoan Warm Period and the Roman Warm Period and the Medieval Warm Period and the cold periods in between. There have been ups and downs since forever.
Over the last 150 years there have been 30-year warming periods and 30-year cooling periods (another of which, if I read the runes correctly, we are about to move into).
So what exactly are you trying to ask?
Mike, I wouldn't even go that far. All climate is local. I challenge anyone to confidently state that the climate in central Africa, or central Australia, went through neat phases such as you describe. You might be able to make that statement about the areas covered by the CET - I don't know. But globally - I think that's a big leap which is not supported by data - even assuming that the concept of global temperature (except in delineating large events such as ice ages) means anything useful.
Dave: You have to have followed the history to know that past pauses are not as important as the current pause. All past pauses were widely acknowledged as solar-influenced natural variation. Hadley modelers then assumed that natural variation was in decline after 1960 or so (in line with the flattened sunspot counts) which allowed them to say that the latter half of the 20th century could not be modelled unless manmade warming was included (other mitigating natural factors like PDO shifts or ocean cycles - which actually originated with skeptics - were dismissed out of hand then as insignificant). Following from this circular argument they then declared that manmade warming therefore now dominated natural variation and the models, with that inbuilt assumption, dutifully produced a corresponding parabolic future increase in global temperature. Any pause in the 21st century was at that point implicitly ruled out by this assumption and hence thermageddon was declared by the Hadley-inspired-IPCC. Despite post-facto excuses now the mainstream scientists did not say then that we should expect another temperature plateau because their assumption-derived conclusion didn't allow for it.
Now the fact that there is a new 17-year long pause means the initial assumption about declining natural variation was wrong, hence they don't understand the mechanisms of natural variation, hence they cannot assume it is in decline, cannot add in manmade warming to fill the gap and cannot plausibly declare that there is any manmade warming at all. The upshot is that they have no scientific basis for any alarmist warming scenario. And i have not even mentioned the fact yet that stratospheric cooling also paused, which in itself invalidates the AGW theory because that was declared by the IPCC to be the one true fingerprint of AGW.
What we are left with then is a probable natural, gentle recovery from the little ice age; which, I might add, nobody has yet given an explanation for either. To my mind, finding a mechanism for past cooling events is the real key to finding what natural variation actually consists of.
johanna
I would agree. My take on the "climate is always changing" argument is that it is equally true to say that climate doesn't change, at least fundamentally. Temperate is always temperate, sub-tropical is always sub-tropical, and so on. There will be some very minor variation around the edges but the annual temperature variation (not to mention the daily variation) is many times greater than the sort of fractions of a degree that the panic-mongers are claiming presages disaster.
The graph I was referring to above in the context of roughly the annual range here in central France is virtually a straight line drawn freehand. Nothing there to frighten the horses.
Yes, AMO is just a manifestation of the global multidecadal oscillation. The oscillation is global because it can be seen in all temperature indices (NH, SH, SST, land...). Take any temperature index and the 'same' oscillation is there.
http://www.woodfortrees.org/plot/hadcrut4tr/from:1880/detrend:0.655/plot/hadcrut4tr/trend/detrend:0.655/plot/esrl-amo/plot/esrl-amo/trend
http://www.woodfortrees.org/plot/hadsst3sh/from:1880/detrend:0.71/plot/hadsst3sh/trend/detrend:0.71/plot/esrl-amo/plot/esrl-amo/trend
The long term linear trend (secular trend) is also an oscillation, only the longer cycle (~200 year cycle and longer too). It seems that both the ~60 year and the ~200 year cycle are plateauing at this point. That means the cooling will be stronger than in the 50s/60s.
Edim, this is not Judy Curry's. Leave the O/T advocacy of your personal theories elsewhere.
Mike Jackson, well yes in the sense that the best predictor of tomorrow's weather is today's. But we have to build major events like ice ages into it as well.
Johanna, ? I was responding to lapogus' (and Dave's) comments. It's not O/T either and it's not my personal theory. The pause is not a pause - it's a peak in the ~60-year cycle and very likely in the ~200-year cycle as well. IMHO.
IMHO exactly. That is not what this thread is about.
Why does everybody insist on calling the peak a "pause"?
johanna
I hate to disagree but I don't believe you have to consider ice ages in this discussion.
The climate change debate/scam/meme, call it what you like, is predicated on the effect of CO2 on current temperatures. Even climatologists are not suggesting that there is anything we can do to predict, mitigate or adapt to ice ages.
I agree with your point that climate is local and BEST has provided data that show that around one-third of weather stations have been reporting a cooling trend rather than a warming one which bears that out.
(As an aside, how would the trend be altered if Hansen's interpolations to account for missing stations in the Arctic or the 1990 decision to reduce the number of stations, giving priority to getting rid of those most likely to show a cooling, were re-adjusted or ignored? Richard Verney has a point.)
Mike, as a policy analyst, your references to "Hansen's interpolations" leave me cold. It is unlikely that the general population would be any more excited.
I'm not a scientist. My perspective is from public policy, politics and stuff that anyone who can work through the logical conclusions of a premise has. You and Edim can please go and slug it out elsewhere.
Dave,
Have a look for yourself: http://www.woodfortrees.org/
BTW, I fiddled around for quite a while on WFT and couldn't produce figures anything like the ones that Richard Black showed on his slide. Anyone know why that is? I used the GISS data, as he mentioned that was what he used, but I couldn't get trends remotely like his. Or was he not talking about trends? If not then what the hell was he talking about?
P.S. Dave, you don't know a bloke called John do you?
Johanna, from the public policy perspective, that's what's in store. Cooling (few decades at least). We are very likely past the peak of the ~60 year cycle, and a longer cycle (~200 y?) seems to be at the max too. Sun is correlating (a very weak cycle). This is all not really controversial, I thought. Sorry if O/T.
Edim, you're one of those monomaniac bores that we all have to suffer through life. In a previous generation, you'd be pinning us to the wall while regaling us with your tales of life in India and the Near East.
Go away. You are the Club Bore.
Blimey johanna. Did he rape one of your pets or something?
Johanna, Club Bore? Well I'm not here to entertain you.
Dave, regarding previous pauses, according to the 'official' climate indices, not since the 'pause' (cooling actually) that ended around 1975, roughly when the hypothesized AGW became significant.
http://www.woodfortrees.org/plot/hadcrut4gl
James Evans
If you notice, I got the other barrel.
For what I'm not sure but I'll just get my coat and go quietly I think.
Could everyone take a deep breath please.
I was keeping my head down in case she had a triple barrel.
I am still not sure what Edim did which so offended Johanna. This thread was about Richard Black's relatively recent attempt to deny the existence of the 15 year pause in warming, which even Hansen and the IPCC accept. Dave asked a question, and few of us gave some answers, and Edim rightly pointed out, that the pause is more likely a plateau, and gave some reasons why. This is a science blog and I don't think it was far off topic if at all. </ducks head back under kitchen table>
Joanna, can we come out now?
Sorry about grumpiness, it was OTT. Apologies to all who got caught up in it.
But in terms of convincing the general public, which is what really matters, these arcane and endless discussions of a few people's pet scientific theories achieve nothing except to turn people off. That is not how the CAGW bandwagon got rolling, and it is now how it has been and will be stopped. The choir are preaching and arguing among themselves, while the congregation sits there baffled and yawning.
When somebody in the congregation asks whether there have been previous climate plateaus, discussing the issue in Latin is not a useful response - especially while the CAGW preacher is in the pulpit declaiming (in English) that we need to cleanse ourselves of sin or face Armageddon.
lapogus, thanks for helping my abandoned old Grand Canyon infographic live on. I didn't promote it much since back in 2010 there was an ongoing pushback against circumstantial arguments, as it was claimed by statistics wonks that such adjustments didn't really affect the policy relevant averages. The uncanny match of the AMO to the global average also made it into a naughty infographic:
http://oi56.tinypic.com/2reh021.jpg
However, to the extent that such "oscillations" are created by mere de-trending of temperature records makes the match readily subject to claims of circular reasoning.
"However, to the extent that such "oscillations" are created by mere de-trending of temperature records makes the match readily subject to claims of circular reasoning."
NikFromNYC, the AMO is also de-trended, so it's not circular reasoning. De-trending the AMO and then calling it an oscillation with no trend is nonsense. The secular trend in AMO is part of AMO and it's very likely another (longer) cycle. Here's the not de-trended AMO:
http://www.climate4you.com/images/AMO%20GlobalAnnualIndexSince1856%20With11yearRunningAverage.gif