So, Global warming hasn't stopped? Ok, in the last 10 years it has not got progressively hotter, but it is not really possible to be certain of a trend over a short period; also the nature of these records are that you do not get a smooth result - many factors can also obscure any underlying trend. BUT it is not getting any cooler - see the record of warmest years below:

Year Global[44] Land[45] Ocean[46]
20 warmest years on record (°C anomaly from 1901–2000 mean)
2005 0.6183 0.9593 0.4896
2010 0.6171 0.9642 0.4885
1998 0.5984 0.8320 0.5090
2003 0.5832 0.7735 0.5108
2002 0.5762 0.8318 0.4798
2006 0.5623 0.8158 0.4669
2009 0.5591 0.7595 0.4848
2007 0.5509 0.9852 0.3900
2004 0.5441 0.7115 0.4819
2001 0.5188 0.7207 0.4419
2008 0.4842 0.7801 0.3745
1997 0.4799 0.5583 0.4502
1999 0.4210 0.6759 0.3240
1995 0.4097 0.6533 0.3196
2000 0.3899 0.5174 0.3409
1990 0.3879 0.5479 0.3283
1991 0.3380 0.4087 0.3110
1988 0.3028 0.4192 0.2595
1987 0.2991 0.2959 0.3005
1994 0.2954 0.3604 0.2704
1983 0.2839 0.3715 0.2513


10 of the 11 hottest years are in the 21st century. The pattern of where is warming may be changing, but we are still seeing average temperatures far above anything expected in the last century.

The BEST data shows no warming for about 13 years.

Phil Jones of Climategate fame acknowledged dimilar about 1 year ago.

Despite an increase of CO2.

Whats the theory again? Increasing CO2 causes global warming?

Where can I buy a thermometer that reads to 4 decimal places?

13 years? That's so you include 1998. which at the time was WAY above the curve of warming. You expect colder years also. if we take two 5 year periods, in 1999-2003 global land warming averages 0.4978 above the 20th century mean, while in 2004-2008 it was 0.5519. That's still warming AND is increasing at a rate above the 20th Century average. I know if you pick different 5 year sets you can get a different answer, but that is why picking a small range of years to suit your presumptions is statistically very poor - my data is just as valid. it also explains why climate is usually calculated as the mean of a 30 year or greater period. If you use the last 30 years, then the mean nearly always goes up every year - because even a cold year now is hotter than a hot year 30 years ago.

rick wrote:13 years? That's so you include 1998. which at the time was WAY above the curve of warming. You expect colder years also. if we take two 5 year periods, in 1999-2003 global land warming averages 0.4978 above the 20th century mean, while in 2004-2008 it was 0.5519. That's still warming AND is increasing at a rate above the 20th Century average. I know if you pick different 5 year sets you can get a different answer, but that is why picking a small range of years to suit your presumptions is statistically very poor - my data is just as valid. it also explains why climate is usually calculated as the mean of a 30 year or greater period. If you use the last 30 years, then the mean nearly always goes up every year - because even a cold year now is hotter than a hot year 30 years ago.

The temperature has not increased for about the last 13 years despite increased co2 levels. The measurements (to 4 decimal places) do not agree with the theory - perhaps the theory is wrong.

According to the theory the planet should be much hotter - but its not. Nothing to do with cherry picking. It was the alarmists best kept secret until Phil Jones spilled the beans - even he acknowledged there was no warming.

I did not pick a 5 year period to make a point - you did. I simply looked at the last 13 years data and stated the obvious - there has been no warming, it is basically a flatline.

The alarmist theory and models did not predict this and cannot explain it. The theory and models say increased co2 = increased heat.

Looks like the theory and models are wrong. A growing problem for the alarmists. Reality is intruding on your fantasy.

I think you will aatempt to change reality - nothing unusual about that!!!

I have made no presumptions and then looked for small subsets of data to support them - but you did.

It is very simple - THERE HAS BEEN NO WARMING FOR ABOUT 13 YEARS.

No amount of statistical obfuscation can change that simple fact.

THERE HAS BEEN NO WARMING FOR ABOUT 13 YEARS. FACT.

John Daniel:

“We make a mistake, anytime the temperature goes up, you imply this is due to global warming,” he said. “If you make a big deal about every time it goes up, it seems like you should make a big deal about every time it goes down.”

JC comment: Well somebody had to finally say this, thank you John Daniel.

Ben Santer:

For a decade, that’s exactly what happened. Skeptics made exaggerated claims about “global cooling,” pointing to 1998. (For one representative example, two years ago columnist George Will referred to 1998 as warming’s “apogee.”) Scientists had to play defense, said Ben Santer, a climate modeler at Lawrence Livermore National Laboratory.

“This no-warming-since-1998 discussion has prompted people to think about the why and try to understand the why,” Santer said. “But it’s also prompted people to correct these incorrect claims.”

JC comment: Too bad this didn’t prompt Santer and others to wonder how much further along we would all be in understanding this if they had paid some attention to the skeptics

http://judithcurry.com/2011/10/27/candi ... #more-5489

Sorry, Ronan, that's not on. you can't just take the warmest year last century and say there is no warming since then. Annual mean temperatures vary a lot (because of weather!), up to 0.3 degrees or more, enough to hide 50 years of warming! and if plotted as such the graph just zigzags and trends are not clear. So let's be scientific. if we look at the 5 year rolling mean (which is used by many climatologists), for the last 10 years (that includes 1998 for some of them, ok?), and we plot it, it still shows a weak warming trend, even if it peaked about 3 years ago. this warming trend is about 0.05 degrees for the decade - which if continued, would see global temperatures up another 0.5 degrees in a century. Not a lot, but actually not substantially less than last century. So although more tenuous, the data still supports the hypothesis that global warming hasn't stopped. The next 10 years will tell.

Anyway, global warming is only one symptom of climate change - the climate could flip to a more stable model, which may not be warmer, but could be a lot different - warming in earlier days which caused massive ice sheet loss led to short term cooling - in some areas- as a result of probable disruption of Ocean currents . The issue is that we DO NOT KNOW what climate effects global warming leads too; we are conducting the experiment right now and we are part of it.

rick wrote:Sorry, Ronan, that's not on. you can't just take the warmest year last century and say there is no warming since then. Annual mean temperatures vary a lot (because of weather!), up to 0.3 degrees or more, enough to hide 50 years of warming! and if plotted as such the graph just zigzags and trends are not clear. So let's be scientific. if we look at the 5 year rolling mean (which is used by many climatologists), for the last 10 years (that includes 1998 for some of them, ok?), and we plot it, it still shows a weak warming trend, even if it peaked about 3 years ago. this warming trend is about 0.05 degrees for the decade - which if continued, would see global temperatures up another 0.5 degrees in a century. Not a lot, but actually not substantially less than last century. So although more tenuous, the data still supports the hypothesis that global warming hasn't stopped. The next 10 years will tell.

Anyway, global warming is only one symptom of climate change - the climate could flip to a more stable model, which may not be warmer, but could be a lot different - warming in earlier days which caused massive ice sheet loss led to short term cooling - in some areas- as a result of probable disruption of Ocean currents . The issue is that we DO NOT KNOW what climate effects global warming leads too; we are conducting the experiment right now and we are part of it.

There are some interesting quotes from climate scientists in this article that highlight a large degree of uncertainty with respect to the climate system, and the human role in it, even among scientists closely involved with the IPCC reports. The long article focuses on the question

‘Why, despite steadily accumulating greenhouse gases, did the rise of the planet’s temperature stall for the past decade?”

Kevin Trenberth:

The hiatus [in warming] was not unexpected. Variability in the climate can suppress rising temperatures temporarily, though before this decade scientists were uncertain how long such pauses could last. In any case, one decade is not long enough to say anything about human effects on climate; as one forthcoming paper lays out, 17 years is required

JC question for Kevin Trenberth: Please remind me of when you first thought there would be a hiatus in the warming.
http://judithcurry.com/2011/10/27/candi ... #more-5489
http://www.eenews.net/public/Greenwire/2011/10/25/1

Rick: So many words to avoid addressing the central issue: why has the planets temperature stalled despite increased co2 (and other gases)?

Trenberth implies 17 years of data is required. Not long to wait - 3 or 4 years - depending on how you measure it. I will wait. And as Curry asked of Trenberth: when did you first think there would be a hiatus in the warming?

Even the diehard warmists agree there has been no warming.

Q: When did the models predict the hiatus? A: Never.

Q: Do the models outputs match observed measurement? A: No

THERE HAS BEEN NO WARMING FOR ABOUT 13 YEARS DESPITE INCREASED CO2

Here's an excellent middle-of-the-road article or us who think that neither of the extreme opinions are proper. but the cures applied are almost disasterous.

"The problem is that you can accept all the basic tenets of greenhouse physics and still conclude that the threat of a angerously large warming is so improbable as to be negligible, while the threat of real harm from climate-mitigation policies is already so high as to be worrying, that the cure is proving far worse than the disease is ever likely to be."

http://wattsupwiththat.files.wordpress. ... ey_rsa.pdf

THERE HAS BEEN NO WARMING FOR ABOUT 13 YEARS DESPITE INCREASED CO2

As i have pointed out, using 1998 as a baseline is not sensible, as it was exceptionally warm. Use practically any other year and there has been warming. What is perhaps surprising is that 2 years have been as warm as 1998 already. Global temperatures vary a lot from year to year - it is averages that count. To compare everything to 1998 is clutching at straws. There have been dips in temperature for a few years before (and this isn't a dip, just a slowdown). I expect that 2011 will provide another 'warmish' year - certainly saw some new records in the UK.

even james hansen concedes there has been no warming since 1998. as does phil jones.

hardly runaway global warming. the hansen /jones /ipcc best case scenarious forecast we should be 1-2 degrees hotter.

i recall some 20 years ago that we would be in a "death spiral" if we dont act NOW. not quite right! we are being still told we must act now to save ourselves.

if averages count, what is the point of citing "some new records in the uk". a review of individual country records show no warming at all over the long term. is this the same uk where snow was predicted to be a thing of the past and then experienced record cod winters (and more along the way)? - much to the embarrassment of the uk met office (who are still requestng even more money for an even bigger computer so they can provide "better" forecasts - using the same data and models). oh dear!

i understand they are preparing for another record cold winter in the uk, but i guess thats weather, not climate.

but i forgot - global warming does not just mean a hotter drier world - it also means a colder wetter one also. it seems that "climate change" means whatever the zealots want it to mean as long as it gets us all to reduce our carbon footprint.

the simple point is there has been no warming for about 13 years - the models did not show this and the models fail when compared to observed data.

the same models that predicted runaway global warming and underpinnned the subsequent demand for immediate action to save us from disaster.

the same people are using the same models to make the same alarmist predictions. and all based on fractions of a degree, which in turn are based on averages of averages.

the previous dips you mention occured with "less" co2. the theory is more co2 = more heat. the dips from about 1940 to about 1960 were in a world with less people and less emmissions. since then co2 has increased "alarmingly", but the temperature has not. maybe this is natural variability?

coversely, the large rise from about 1910 to about 1940 is also attributed to co2. does not make sense.

there in no way of avoiding the simple fact that temperatures have not increased for about 13 years despite "huge" increases in co2.

i am happy to wait another 3-4 years and suspect the temp will drop, and this will be statistically significant according to trenberth. there is not much of a case for immediate action to save us from runaway warming.

none of the models can replicate the past trends, but we are expected to accept their doom and gloom forecasts. just like the uk met office predicted snow as a thing of the past. cry wolf!

as TJ posted:

"The problem is that you can accept all the basic tenets of greenhouse physics and still conclude that the threat of a dangerously large warming is so improbable as to be negligible, while the threat of real harm from climate-mitigation policies is already so high as to be worrying, that the cure is proving far worse than the disease is ever likely to be."

Well, everything about predicting what causes climate is down to probability; you need a whole planet as a test bed to find out the effects. All we know is that what laboratory tests and scientific measurements that can be done tell us that our climate is the result of a certain amount of solar radiation, internal heat from within the planet (mainly from radioactive decay), greenhouse effects from gases in the atmosphere and changes to the planets albedo. If all these things were the only things affecting our planet then it's climate would be very stable and predictable. Unfortunately it is not. From year to year, weather can change a lot and it is nearly impossible to predict what next year's weather will be like. So one, two even 5 years provides a very unstable base on which to predict anything. All we can say, is that in the absence of any other evidence, that the warming over the last 150 years is LIKELY to be due to increased Carbon Dioxide. No-one can suggest another LIKELY cause. Of course, other things have affected the climate during this period also, such as changes to Albedo, sunspot cycles, volcanic eruptions and ocean current fluctuations (such as el nino, our understanding of what effects ocean currents is still quite poor). But as far as can be told these effects are small or short term - but this and other weather effects causes a lot of noise on the global climate record. No-one really know what caused the temperature drops recorded in the 1880's, 1900-1910 or the 1940's (and a period from 1945-1975 when temperature basically fairly stable). but anyway, the dominant trend in the 20th century was warming (temperature up about 0.7-0.8 degrees Centigrade).

One suggestion is that weather patterns may change, with greater variability. This is what the Northern hemisphere is currently experiencing, with colder, wetter winters and hotter, drier summers being more frequent. As for CO2, well, levels are going up and we know it causes a greenhouse effect (without it the planet would be in a deep ice age). It is possible that their are mechanisms that alleviate some of that, but some of this will feed through to global warming, it is not if, but how much. We also need to bear in mind that it takes a long time for the oceans to warm - 500 years it has been estimated - so the oceans are still acting as a heat sink for say the next 400 years. Also, as oceans warm, they can hold less CO2 - so levels may go higher (feedback). There are other feedback events - warming increases the release of other greenhouse gases, like methane, as it is released from thawing Arctic soils and warming ocean floors - evidence of this is already being seen. These feedbacks could increase global warming considerably and be difficult to stop - but are impossible to quantify accurately.

I am not a mad climate mitigation believer, but i do think the precautionary principle is a good idea. Also, we should think about sustainable development - resources are not infinite and sustainable development conserves resources and at the same time should have some benefits in reducing CO2 emissions.

Finally, it has been estimated that a temperature rise of 4 degrees would make parts of the planet uninhabitable and cause breakdown in human society, while natural environments would nearly all be totally disrupted - including farming. i am sure the human race will survive, but only a small part of it. Two degrees is now generally accepted as the point at which global warming becomes extremely dangerous. Climate models predict (typically) 2.5 - 4.5 degrees of warming in the 21st century. So we could be at a critical point within 50 years. Due to thermal inertia, it will take some time for warming to stabilise, so a further 0.5 degrees centigrade of warming is expected even if carbon dioxide levels stop rising. So far, no-one can explain why the temperature rose in the 20th Century except as a result of Carbon Dioxide levels. The fact that the increase has fluctuated is due to other factors, some known, some probably not. Unfortunately science has only been in a position to measure the inputs in recent times, historical climate factors have to be inferred indirectly.

And here is an extract from Richard Black's blog for the BBC suggesting that warming HAS occurred:

De-bunking the Mail/GWPF claim that the Berkeley data shows warming has stopped takes marginally longer.

They produce a graph of monthly average temperatures from the Berkeley dataset that is, as far as I can see, accurate in the sense that it has put the dots in the right place.


GWPF's graph lacks error bars and a trend - and is skewed by a pretty obvious data "outlier"
It claims that the graph shows "a statistically perfect straight line of zero gradient". But there is no line given, and no error bars.

Worse, they produce no statistics. It's just a graph, and we're implicitly invited to use our eyes to validate the claim that it shows a flat trend.

A second issue is that weird penultimate data point, which even to the most casual observer would surely stand out as oddly low.

Did the world suddenly get 2C colder in April 2010, and then return to its previous balmy state in May?


There is little sign of cooling in the Arctic, where sea ice volume is decreasing year on year
Of course not. And when you go into the Berkeley dataset, you see that the last two readings it gives for 2010 - April and May - come with huge uncertainties attached, nearly 3C in fact, way bigger than anything else in their records.

I suspected - and when I spoke to Prof Muller on Monday, he confirmed it - that this was down to a dearth of readings.

Blogger Nick Stokes delved more deeply than I did, and found out that the only data for those two months came from 47 weather stations in Antarctica.

Simply put, at the time Berkeley did their analysis, they had not taken delivery of anywhere enough data to say anything meaningful about those two months.

GWPF and the Mail neither mention the huge uncertainties, nor put them on their graph.

Even visually, if you take these data points out, it begins to look as though there might be an upward trend.

Anyway, visual inspection is something best left for paintings and photos. For numbers, you need statistics.

Tamino, the enigmatic climate blogger who runs the Open Mind site and keeps his identity deeply under wraps, has run the numbers.

He calculates that if you omit those two Antarctic-only data points and end the run at March 2010, you see an upward warming trend of 0.14C/decade - smaller than the average that Berkeley found for the late 20th Century, but still positive.

Tamino also calculates that if you start just one year further back, the warming trend increases to 0.27C/decade.

For a quick comparison, we ran the Berkeley numbers through a standard spreadsheet package and came up with very similar numbers to Tamino. And if you start a year further back, in 1999, you see a bigger rate still - 0.30C/decade.

So it seems my analysis has been vindicated by experts with access to the latest data - in fact they find a higher rate of warming.

And:

Starkly, it shows that when you come down to a period as short as a decade - and GWPF/Mail used less than a decade - the uncertainties swiftly get too big to show anything reliably.

Andy Revkin of Dot.Earth tweeted a reminder this week that this issue was addressed formally two years ago, in a paper in Geophysical Research Letters by David Easterling and Michael Wehner.

Their top-line conclusion: "The climate over the 21st Century can and likely will produce periods of a decade or two where the globally averaged surface air temperature shows no trend or even slight cooling in the presence of longer-term warming".

Simply put, there are just too many short-term wiggles in the data because of the El Nino Southern Oscillation and other factors. You need more time.

Richard Muller made the same point in our brief phone conversation.

"You could equally well take a period between about 1980 and 1995, and it would be equally 'flat'," he said.

"It simply shows that if you allow yourself to use the non-scientific process of picking your starting point in order to get the result you want, you can do that."

Hmm - 13 years .... odd number.

Full text: http://www.bbc.co.uk/news/science-environment-15538845

Richard Black from the BBC - hardly a scientific expert. Widely acknowledged as a crank. He incorrectly points to other "flat spots" in his talk - very wrong:

After this amateurish display things get a little more confused. When describing the data (HadCRUT3v Global data this time) Black spoke of a “relative plateauing” in the past decade, even though his crude trend analysis given a moment before didn’t show it. He then said, “you could make a case that global warming has plateaued, but if you are going to say that you would also have to say global warming has plateaued there, and there and there.”

He was pointing at the much shorter standstills seen in the data in previous decades. These are well understood, and not comparable to the past decade. In two cases they are due to volcanic eruptions (Mt Pinatubo in 1991 is obvious in the data, and there have been no such eruptions in the past decade). It is highly misleading to compare apples and oranges in this way. Science can explain the slight pauses seen in the two decades before this one, though it has a harder task explaining the 1940-1980 standstill.

The point is that previous flat periods, the cause of which is debatable, occurred before the date given by the IPCC at which mankind’s influence on the global climate was dominant (sometime around 1960 – 80). A hiatus in warming nowadays is a somewhat more important part of understanding what mankind’s influence on our planet is, hence the current considerable discussion about possible decadal influences on climate.
http://www.thegwpf.org/the-observatory/ ... stics.html

Sometine in the 1980's (forget exact date) but some 20 to 30 years ago, Hansen (the godfather of global warming of alarmism), testified to a US congressional hearing that unless we stop co2 emmissions NOW there would be runaway global warming. Since Hansen started this scare campaign temperature has behaved more in line with naural variabilty.

The theory does not accord with real world observations. According to the "experts" it should be 2 to 4 degrees hotter. Its not. They are wrong.

The 2 degrees you mention as being the accepted number that will reach the "tipping point" is not based on any scientific principle or study - it was created by german policy makers to scare the bejusus out of a gullible public.

The so called Precautionary Principle is not a scientific principle either. It is a cheap put-down to prevent discussion. If ths principle was applied in the course of human development we would still be sitting in caves, freezing in the dark, afraid to bang two rocks together in case we made fire.

No matter how you look at it - the planet has not "warmed" in about 13 years - despite massive increases in co2.

Of course its not all about carbon (doixide):

McKibben and his allies figure the $7 billion Keystone XL — which was barely on their environmental radar screen a year ago — could be a galvanizer because the 1,702-mile underground pipeline would be a "fuse to the biggest carbon bomb on the planet."

"If the tar sands are thrown into the mix it is essentially game over," Hansen, the National Aeronautics and Space Administration climatologist, explained about reclaiming a stable climate. "The principal requirement is that coal emissions must be phased out by 2030 and unconventional fossil fuels, such as tar sands, must be left in the ground."

Another Hansen prediction of thermageddon! I wonder how well this one will stack up against his other (failed) predictions?

http://www.reuters.com/article/2011/06/ ... 3820110627

The GWPF is hardly an independent body. It exists purely to debunk global warming and further 'energy interests'. it has 80 members but 98% of it's funding is secret. No wonder that in it's recent reports the only things they are for is exploiting shale gas.... and they claim they have no funding from energy companies ...... Yeah. And here's a comment about them-

Bob Ward, policy and communications director of the Grantham Research Institute, as saying "some of those names are straight from the Who's Who of current climate change sceptics...It's just going to be a way of pumping material into the debate that hasn't been through scrutiny".

"The scientific community would come down on me in no uncertain terms if I said the world had cooled from 1998. OK it has but it is only 7 years of data and it isn't statisically significant" Phil Jones 07/05/05

It's now 2011, nearly 2012, so about 13 of "global cooling" (according to Jones), or at least "no warming" (to be kind).

Trenbert/Santer reckons it will take about 17 years of data to be statisically significant. Not long to wait.

As for quoting the 2000's as the hottest decade ever: the planet has been warming since the little ice age. In general terms 1890 was warmer than 1900, 1920 was warmer than 1910, etc. These increases cannot be attributed to CO2.

Saying the 2000's are the hottest decade ever is meaningless drivel.

THERE HAS BEEN NO WARMING FOR ABOUT 13 YEARS DESPITE INCREASED CO2

The natural variability in Annual mean temperature from year to year has been pretty consistent, with the Maximum difference between consecutive years being about 0.3 degrees centigrade. With a rate of warming of about 0.1 degree centigrade per decade (depends over which time period you choose, but average of 0.07 if you use the whole of the last century) it means that an exceptionally hot year WILL be above the average for a long time (about 15 years, roughly). it is also why you cannot really work off of individual years. It is still a fact that if you were to take average temperatures by decade, the last decade is the warmest. What you can say, is that temperatures like 1998 are now normal, having been approximately reached at least twice since. But to be sure that warming is continuing, you need a long time frame as the natural variability can obscure changes for a long period. As Phil Jones said - 7 years data is not statistically significant. He didn't say that 13 years from a cherry picked date was either.

Repent ye sinners the end is nigh

Here we go again - more alarism from the eco-loon nutjobs:

World headed for irreversible climate change in five years, IEA warns
http://www.guardian.co.uk/environment/2 ... ate-change

I have been told this many times over the past 20 years, but it never happens. More "tipping point'" bulldust.

Climate change is inevitable.

Well, some other changes are happening which are presumably related to the climate. Must be the cooling :-" this from the last 10 years.

http://www.bbc.co.uk/news/science-environment-15721263

rick wrote:Well, some other changes are happening which are presumably related to the climate. Must be the cooling :-" this from the last 10 years.

http://www.bbc.co.uk/news/science-environment-15721263

And this from the IPCC (via Richard Black of all people):

http://www.bbc.co.uk/news/science-environment-15698183

And for the future, the draft gives even less succour to those seeking here a new mandate for urgent action on greenhouse gas emissions, declaring: "Uncertainty in the sign of projected changes in climate extremes over the coming two to three decades is relatively large because climate change signals are expected to be relatively small compared to natural climate variability".

It's also explicit in laying out that the rise in impacts we've seen from extreme weather events cannot be laid at the door of greenhouse gas emissions: "Increasing exposure of people and economic assets is the major cause of the long-term changes in economic disaster losses (high confidence).

"Long-term trends in normalized economic disaster losses cannot be reliably attributed to natural or anthropogenic climate change."

I think thats long-winded IPCC speak for "we're not sure if its getting hotter or colder. Even Black expects that governments will insist on "different conclussions" in the final report because so much money is at stake.

The good news is that we will be able to notice the extreme efforts the warmists go to in order to alter the text. The next version will likely say: if it warms it is due to mankind and CO2, if it cools it is due to natural variability.

Funny - the experts at the IEA say we are doomed within 5 years because of CO2, but the experts at the IPCC say its not? Go figure

Rick - for once I think you are right - it is due to the cooling of the last 10 years :-"