Forecast for warming revised downward.
The UK Met Office has revised one of its forecasts for how much the world may warm in the next few years.
It says that the average temperature is likely to rise by 0.43 C by 2017 – as opposed to an earlier forecast that suggested a warming of 0.54C.
The explanation is that a new kind of computer model using different parameters has been used.
The Met Office stresses that the work is experimental and that it still stands by its longer-term projections.
These forecast significant warming over the course of this century.
The forecasts are all based on a comparison with the average global temperature over the period 1971-2000.
The earlier model had projected that the period 2012-16 would be 0.54C above that long-term average – within a range of uncertainty from 0.36-0.72C.
By contrast the new model, known as HadGEM3, gives a rise about one-fifth lower than that of 0.43C – within a range of 0.28-0.59.
This would be only slightly higher that the record year of 1998 – in which the Pacific Ocean’s El Nino effect was thought to have added more warming.
If the forecast is accurate, the result would be that the global average temperature would have remained relatively static for about two decades.
Blog suspicions
An apparent standstill in global temperatures is used by critics of efforts to tackle climate change as evidence that the threat has been exaggerated.
Climate scientists at the Met Office and other centres are involved in intense research to try to understand what is happening over the most recent period.
The most obvious explanation is natural variability – the cycles of changes in solar activity and the movements and temperatures of the oceans.
The forecasts are based on a comparison with the average global temperature over the period 1971-2000A Met Office spokesman said “this definitely doesn’t mean any cooling – there’s still a long-term trend of warming compared to the 50s, 60s or 70s.
“Our forecast is still for temperatures that will be close to the record levels of the past few years.
“And because the natural variability is based on cycles, those factors are bound to change the other way at some point.”
The fact that the revised projection was posted on the Met Office website without any notice on December 24 last year has fuelled suspicions among bloggers.
However the Met Office says the data had been published in a spirit of transparency as soon as it became available from the computer that produced it.
Future forcings
It describes the decadal projections as part of an experimental effort launched in 2004 to fill the gap between daily weather forecasts and century-long estimates for climate change.
But this is an emerging and highly complex area of science because of the interplay of natural factors and manmade greenhouse gases at a time when a key set of temperatures – in the deep ocean – is still relatively unknown.
One aim of attempting to project the climate on this timescale is to be able to rapidly check the accuracy of the models being used.
A paper published last month in the journal Climate Dynamics, authored by scientists from the Met Office and 12 other international research centres, combined different models to produce a forecast for the next decade.
It said: “Decadal climate prediction is immature, and uncertainties in future forcings, model responses to forcings, or initialisation shocks could easily cause large errors in forecasts.”
However the paper concluded that, “in the absence of volcanic eruptions, global temperature is predicted to continue to rise, with each year from 2013 onwards having a 50 % chance of exceeding the current observed record”.
Scrutiny of Met Office forecasts and climate science generally is set to increase in the build-up to the publication of the next assessment by the UN’s Intergovernmental Panel on Climate Change (IPCC) in September.
Source:
http://www.bbc.co.uk/news/science-environment-20947224
=========================================================
Re: that last paragraph, with the release of the IPCC AR5 leak #2 today, ya think?
Discover more from Watts Up With That?
Subscribe to get the latest posts sent to your email.
Werner, Again, I am refering to the appearence of the data set from 1880 to 2007 as discussed by the authors of the paper, not analalysis of the subsets of that data.
At the risk of repeating myself:
In support of my eyeballing of the accelerating nature of the data from 180 to 2007 (based on over 3 decades experience in examining such graphs):
http://www1.picturepush.com/photo/a/11901124/img/Anonymous/hadsst2-with-3rd-order-polynomial-fit.jpeg
Compare this to the data set Stealy presents and the linear fit:
http://www.woodfortrees.org/plot/hadcrut3vgl/compress:12/offset/plot/hadcrut3vgl/from:1850/to:2010/trend/offset
Werner Brozek says:
” I know this is very small, but certainly no acceleration.”
Shehan appears to be the only one left at WUWT who believes in accelerating global warming.
Ignore him, he is nuts.
Note that D. Boehm advises Werner (and many others elsewhere) to ignore me, but is incapable of doing so himself.
Shehan, as long as you keep peddling your lie that global warming is “accelerating”, I’ll be here to point out to other readers that you are lying.
Philip Shehan says:
January 12, 2013 at 3:56 pm
How do you do italics or bold on this site anyway?
To ital something, put “” before the start and “” at the end. To bold, put “” before the start and “” at the end.
Now as for the acceleration, of course it depends on the length of time. However NOAA says important conclusions can be drawn if certain things do not happen in 15 years. And Santer talks about 17 years. So why should we care if there is an acceleration over 160 years if there is none over the last 15 or 17 years when CO2 has been higher than for 600,000 years?
Sorry!
To ital something, put “less than ()” before the start and “less than, slash (/) i, greater than” at the end. To bold, replace b with i both times.
Sorry again! See formatting in http://home.comcast.net/~ewerme/wuwt/index.html
Thank you Werner.
I don’t at all object to your opinion that the last 160 years should be viewed in the context of the last 600,000.
However I am only commenting on the appearence of the data set in figure 1 c of the paper as chosen by its authors:
Polynomial cointegration tests of anthropogenic impact on global warming
M. Beenstock1, Y. Reingewertz1, and N. Paldor2
To be precise the data set choen by these authors in Fig 1 c is the gistemp dataset from 1880 to 2007 shown below. I am unsure of what the NOAA or Santer (Sorry, who is he?) would make of an assertion that examination of the 17 year period 1940 to 1957 indicates a decline in the entire data set.
http://www.woodfortrees.org/plot/gistemp-dts/from:1880/to:2007/mean:12/plot/gistemp-dts/from:1940/to:1957/trend/plot/gistemp-dts/to:1880/to:2007/trend
(D Boehm may disagree with my assessment regarding what comparison of the whole data set with the linear fit reveals but that does not make me a liar.)
Nice to have a respectful discussion with someone who does not so personalise points of difference.
Philip Shehan:
At January 12, 2013 at 7:54 pm D Böehm Stealey wrote
In your post at January 13, 2013 at 12:10 am you say
The recent deceleration has been explained to you in several ways an you have personally linked to a graph which shows the DEceleration. Indeed, the trend has decelerated to zero over the most recent 16+ years.
Please explain how it is possible for D Böehm Stealey (or anybody else) to be “respecful” when pointing out the clear an indisputable fact that you are lying.
Richard
Shehan,
You are either an intelligent individual, or you are deluded. I suspect that you are intelligent, and therefore you know that there has been no acceleration of global warming.
Therefore, you are peddling deliberately false propaganda by claiming non-existent “acceleration” in global warming. That is simply not happening. So why are you lying about it?
As we see, the long term global warming trend is decelerating [the green line]. Long term, the naturally rising temperature trend is gradually moderating. There is not – and there never has been – any acceleration of global warming since the end of the LIA.
Even the warmist crowd now acknowledges that there has been no “acceleration” in global warming. You are alone in your prevarication. Why is that? Everyone else here can see that there has been no acceleration in global temperature. More than that, global temperatures have stopped rising. So tell us: why are you pretending otherwise? Is it because your fragile ego cannot allow you to admit you are wrong, even in the face of overwhelming scientific evidence?
You are truly embarrassing yourself, Shehan, by your insistence that War is Peace, Ignorance is Strength, and Global Warming is Accelerating. It is not. No one else believes you. So why do you keep insisting that something non-existent is real?
It does no good to argue with shehan, even if he admits a point, he will later deny such an admission. This has happened with me several times. For instance, regarding the product of climate models, which Shehan has changed his position on several times in discussions with me.
@Philip Shehan: I will chip in with a layman interpretation of how I see this argument has been developing. I freely admit I am clearly not as educated in matters of statistics as everyone posting here but still…here goes. In your response to Werner you mention the 17 year period 1940 – 1957 and the cooling trend over this time. You then say what would Santer make of this representation of the overall trend. I think this is the crux of where you are in disagreement with others. You are looking at it from the point of view that these 17 year periods are “samples” if you like, of the overall trend. For you there is one overall trend and no matter where you take a “sample trend” ie 1940-1957, 1970-1987, or 1996-2013, all these samples should be representative of the overall trend.
Because they differ you take this as evidence that 17 years cannot be a long enough time period to get a true estimate of the overall trend and hence only the entire period can be examined to truly get a sense of the entire trend.
What others are saying is that it is not one simple overall trend. There are many different things happening over the entire time period, stalls in the rise, periods of time where the trend is negative, periods of faster increase, periods of slower increase, and a recent period of no increase. Their opinion is that all these different periods require analysis of their own rather than treating the entire time period as if it were one continuous rise (correct me if I’m wrong everybody). By doing this you are effectively ignoring that things like the recent pause (or at the very least deceleration) in temperature increase is happening. What they are saying is that they believe their interpretation more accurately reflects reality than your own, since it is looking at the overall trend in more detail by breaking it into smaller “chunks”. Whereas you believe said “chunks” are only samples, and should all effectively show the same trend, and if not they cannot be of sufficient sample size.
For instance, what Werner said was that regardless of whether the overall trend was accelerating for 160 years (and he did not concede that it was, he was just saying for the sake of argument lets assume it was), the most recent 17 years of the trend suggest that temperatures are no longer increasing. Hence the overall claim that the rise in temperatures is still accelerating cannot be true. He is saying that the last 17 years alone negate the possible existence of a continuing accelerating trend.
Philip Shehan:
At January 12, 2013 at 5:53 pm you say
Oh! The “appearance”! At last I understand your claims!
I strongly advise that you visit an optician with a view to obtaining needed spectacles.
Richard
Here’s something I just sent to NPR:
NOAA posted an announcement that 2012 was the warmest year on record IN THE US. Here’s the link: http://www.ncdc.noaa.gov/sotc/national/2012/13
Your show (Wait, Wait, don’t Tell me) left out those last words. Twice.
The effect was to mislead a portion of your audience into thinking that it was the warmest year GLOBALLY. (Globally, it’s the ninth warmest year on record. I.e., 2012 is well off the average of earlier years in this century.)
Surely you didn’t intend to mislead.
Or am I wrong?
Maybe you just didn’t notice “IN THE US,”
Or maybe you thought it a trivial detail, not worth mentioning.
Or maybe you thought nobody would notice your omission.
Or maybe you thought that nobody decent (i.e., politically correct) could object to your way of putting it, so their opinion doesn’t count. Maybe you rather enjoy treading on their toes.
Wait, wait, don’t tell me. It’s all of the above.
Philip Shehan says:
January 13, 2013 at 12:10 am
Santer (Sorry, who is he?)
See below or google Benjamin Santer 17
http://www.agu.org/pubs/crossref/2011/2011JD016263.shtml
By the way, RSS now shows 16 years and 1 month of no warming, since December 1996.
And when combining the two satellite data, we get 15 years and 1 month of no warming, while CO2 has been going up steadily. See:
http://www.woodfortrees.org/plot/rss/from:1997/plot/rss/from:1997.9/trend/plot/uah/from:1997/plot/uah/from:1997.9/trend/plot/rss/from:1997.9/trend/detrend:-0.0735/offset:-0.080/plot/esrl-co2/from:1997.9/normalise/offset:0.68/plot/esrl-co2/from:1997.9/normalise/offset:0.68/trend
Philip Shehan says:
“Santer (Sorry, who is he?)”
This is hard to believe. Shehan has never heard of Ben Santer?? That can only mean that Shehan is brand new to the debate. Like a teenager, Shehan believes he knows everything climate-related. But when he grows up, he will begin to understand that the world does not revolve around his personal belief system.
It’s a big world out there. Do a search for “Climategate” + “Santer”. Learn the players, and what they are saying.
Werner:
Thanks for the link. Will read it later.
Entirely understand that CO2 content continues to increase while temperature goes up down and sideways.
I presented the following
http://www.woodfortrees.org/plot/esrl-co2/from:1950/to:2013/mean:12/scale:10/normalise/plot/hadcrut3vgl/from:1950/to:2013/mean:12/scale:5/normalise
as an alternative to D. Boehms chart where his use of the isolate function means he is plotting noise (from the WFT site – Isolate (months) Does the same running mean as ‘mean’ but then subtracts this from the raw data to leave the ‘noise’)
http://www.woodfortrees.org/plot/esrl-co2/isolate:60/mean:12/scale:0.25/plot/hadcrut3vgl/isolate:60/mean:12/from:1958
In my response to Boehm regarding this graph and his claim that it demonstrates that CO2 concentration is caused by temperature, I acknowledged that there are many forcing factors other than CO2 which are responsible for temperature. D. Boehm failed to answer my question regarding this (put several times) and says I am not smart enough to get him to answer. He also says that in relation to my question regarding why the downward slope in temperature from 1940 to 1957 (or 55 or 56) does not mean that the entire temperature record shows a decline.
He is right of course. I am not smart enough force him to answer questions which for obvious reasons he does not wish answer.
“Given the complexity of the climate system which involves solar cycles, volacanic eruptions, el nino and la nina events, aerosols and particulates, etc, how does such a near perfect cause and effect relationship between CO2 concentration and temperature operate?”
richardscourtney;
You are well aware that in the other thread, for the benefit of the the slow learners, I have been repeating with the periodicity of a chiming clock that I am commenting only on what the authors of the paper claim an “informal” eyeballing of temperature data from 1880 to 2007 appears to show.
So what do your eyeballs say when comparing how well the linear fits both for the period 1880 to 2007 and the selected 17 year subset
http://www.woodfortrees.org/plot/hadcrut3vgl/compress:12/offset/plot/hadcrut3vgl/from:1880/to:2007/trend/offset/plot/hadcrut3vgl/from:1940/to:1956/trend
matches the data and the upward trending curves match the data in these two plots:
http://www1.picturepush.com/photo/a/11901124/img/Anonymous/hadsst2-with-3rd-order-polynomial-fit.jpeg
http://www.skepticalscience.com/pics/AMTI.png
Shehan has never heard of the notorious Ben Santer, but he pontificates as if he knows which end is up regarding global warming. He doesn’t.
For example, Shehan posts this chart, and claims that it shows accelerated warming. As anyone can see, it doesn’t show any such thing. It simply shows a straight linear rise in natural global warming. And the bogus SkS charts that Shehan keeps posting are not fooling anyone here.
Isn’t it about time you stopped lying about global warming “accelerating”, Shehan?
NASA says get ready for even more global cooling:
http://www.washingtonsblog.com/2013/01/nasa-we-may-be-on-the-verge-of-a-mini-maunder-minimum.html
I have never claimed to be an expert on global warming. It appears to D.Boehms life’s work to the point of pathological obsession. Does he do anything else with his day?
I have claimed to be an expert, with over 3 decades experience in looking at graphs of the kind being discussed here.
Boehm presented a graph which, again based on over three decades of experience I can confidently assert that had it been presented at a scientific conference or to a scientific journal would have been met with scorn and derision. It is this one:
http://tinyurl.com/bkoy8or
He has introduced various devices scale factors and offsets, in particular the horizontal yellow line from the final series 7, for no other purpose than to manipulate the y axis and compress the appearance of the temperature lines. Try it for yourselves. Delete series 7 and replot the graph.
Why has he engaged in this subterfuge? Because he hopes to disguise what he says is not happening in what he describe as “this chart” above.
“This chart” is in fact from Boehm’s own graph from which I removed the extraneous camouflage, leaving a plot of one temperature data set in his chart. I removed the original trend line in Boehm’s graph and substituted two shorter trend lines there but here I reinstate Boehm’s own trend line:
http://www.woodfortrees.org/plot/hadcrut3vgl/compress:12/offset/plot/hadcrut3vgl/from:1850/to:2010/trend/offset
Now you can see what he is so anxious to camouflage the data set by compression of the y axis. He asserts above
“Shehan posts this chart, and claims that it shows accelerated warming. As anyone can see, it doesn’t show any such thing. It simply shows a straight linear rise in natural global warming.”
He needed to compress and flatten the appearance of the temperature data, but it doesn’t work. The uncompressed data clearly shows that it is not well fit by a straight line. The early and late sections are above the linear fit, evidence of acceleration, and a much better fit is obtained with the non linear curve for the same period:
http://www1.picturepush.com/photo/a/11901124/img/Anonymous/hadsst2-with-3rd-order-polynomial-fit.jpeg
And yes, Boehm has been “too smart” to explain his use of camouflaging functions to manipulate the y axis and so flatten the appearance of the curve.
Philip Shehan:
re your post at January 13, 2013 at 3:56 pm
The only “slow learner” seems to be you.
It does not matter what you think the graph looks like: others may think it looks like an elephant.
What matters is what the data shows, and the graph is a pictorial representation of the data. And many pictorial representations can be constructed.
As several people have explained to you, the data shows that global warming is decelerating (i.e. the opposite of the acceleration you assert).
Richard
Well, even though I have the advantage of over thirty years experience in examining precisely this kind of pictorial representation, I cannot believe even the most untrained of eyes would match the temeperarture data to an elephant, unless they were on some serious mind altering subsatances.
In my humble, make that professional, opinion, I think any objective observer would agree that this fit
http://www1.picturepush.com/photo/a/11901124/img/Anonymous/hadsst2-with-3rd-order-polynomial-fit.jpeg
is superior to this fit
http://www.woodfortrees.org/plot/hadcrut3vgl/compress:12/offset/plot/hadcrut3vgl/from:1850/to:2010/trend/offset
Philip Shehan writes:
Philip Shehan: When drawing a straight line through the data from 1880 to 2007, compared to an exponential curve through the same data…Yes, the exponential curve fits the data better than the straight line. However, neither fit is as accurate as breaking down the curve into sections and analysing the trend in each section. When doing so you will note that temperatures are no longer increasing/rate of increase appears to have dramatically slowed (delete as per your own personal bias) according to the data from the last 17 years. So while you can possibly claim the rate of temperatures DID increase, you can no longer claim that the rate of increase continues to accelerate. I think if you just conceded this last point you would encounter far less opposition to your analysis.
Graham,
You wrote.
Philip Shehan: When drawing a straight line through the data from 1880 to 2007, compared to an exponential curve through the same data…Yes, the exponential curve fits the data better than the straight line.
Thank you.
That is the only point I have been making. Because I have been discussing the authors comment concerning the appearance of the entire data set from 1880 to 2007.
Now try to explain that to Boehm and Richard Courtney.
To go back to my first comment on this:
‘Quoting from the paper:
“3.1 Time series properties of the data
Informal inspection of Fig. 1 suggests that the time series properties of greenhouse gas forcings (panels a and b) are visibly different to those for temperature and solar irradiance (panel c). In panels a and b there is evidence of acceleration, whereas in panel c the two time series appear more stable.”
I have no argument whatsoever with the rest of your comment, except the last sentence.
I have never claimed that examination of the last 17 years shows continued acceleration. It does not. But the point I have been making over and over and over again is that choosing subsets of data, whether they go, up, down or level (and you can choose multiple subsets that do any of these things) simply cannot be generalised to a statement of the about 1880-2007 as a whole. Again, the 17 year period from 1940 to 1957 does not show an increase in the upward slope of the data (acceleration). It does not show an upward slope at all. It actually shows a decrease in temperature over that time. It is multidecadal trends I have been discussing.
I disagree with your last sentence: “I think if you just conceded this last point you would encounter far less opposition to your analysis.”
Boehm and Courtney are incapable of understanding this point or pretend not to no matter how many times I make it, and calling me a liar and/or suffering from a visual impairment (which you apparently share).
“Philip Shehan:
At January 12, 2013 at 5:53 pm you say
Werner, Again, I am referring to the appearance of the data set from 1880 to 2007 as discussed by the authors of the paper, not analysis of the subsets of that data.
Oh! The “appearance”! At last I understand your claims!
I strongly advise that you visit an optician with a view to obtaining needed spectacles.
Richard”
And Boehm himself, in a comment to Layman Lurker makes spectacular reversal of his claims about the validity of using the last 15 years of the entire data set to me, writing that we can’t tell anything from a 15 year subset.
“As I have repeatedly pointed out, the only way to see if global temperatures are accelerating is by using a long term trend chart, based on verifiable data. When we view such a chart, it is clear that there is no acceleration of global warming. [The green line shows the long term global warming trend.]”
The chart he produces again has the temperature data artificially compressed in the y axis
http://tinyurl.com/ch49ytb
to camouflage the upward trend away from green line whn the compression is removed.
http://www.woodfortrees.org/plot/hadcrut3vgl/compress:12/offset/plot/hadcrut3vgl/from:1850/to:2010/trend/offset