In the much ballyhooed 2008 NOAA “State of the Climate” report on climate change they state, concerning the climate models, something quite relevant to the issues raised by the new story in the UK Daily Mail:
“Near-zero and even negative trends are common for intervals of a decade or less in the simulations, due to the model’s internal climate variability. The simulations rule out (at the 95% level) zero trends for intervals of 15 yr or more, suggesting that an observed absence of warming of this duration is needed to create a discrepancy with the expected present-day warming rate.”
Source: http://www1.ncdc.noaa.gov/pub/data/cmb/bams-sotc/climate-assessment-2008-lo-rez.pdf
Dr. Roger Pielke Jr. said in 2009:
“Kudos to NOAA for being among the first to explicitly state what sort of observation would be inconsistent with model predictions — 15 years of no warming.”
(h/t to Tom Harris)
Or how about this:
Climategate’s Phil Jones ‘insisted that 15 or 16 years is not a significant period: pauses of such length had always been expected, he said’ in 2012
‘Yet in 2009, when the [temperature] plateau was already becoming apparent and being discussed by scientists, Jones told a colleague in one of the Climategate emails: ‘Bottom line: the ‘no upward trend’ has to continue for a total of 15 years before we get worried.’
‘In other words, though 5 years ago he seemed to be saying that 15 years without warming would make him ‘worried’, that period has now become 20 years’ h/t to Climate Change Dispatch.
Regarding the significance of the period from 1997, recall that Dr. Ben Santer claimed 17 years was the period needed:
http://wattsupwiththat.com/2011/11/17/ben-santers-17-year-itch/
They find that tropospheric temperature records must be at least 17 years long to discriminate between internal climate noise and the signal of human-caused changes in the chemical composition of the atmosphere.
MIT Professor Richard Lindzen said something similar in a WUWT guest post:
There has been no warming since 1997 and no
statistically significant warming since 1995.
Yet, today, we see evidence of the goalposts being moved again as the met Office tries to paint this lack of warming “plateau” as being insignificant:
The models exhibit large variations in the rate of warming from year to year and over a decade, owing to climate variations such as ENSO, the Atlantic Multi-Decadal Oscillation and Pacific Decadal Oscillation. So in that sense, such a period is not unexpected. It is not uncommon in the simulations for these periods to last up to 15 years, but longer periods are unlikely.
So we are at 16 years, soon to be 17 years. What happens when we hit 20 years?
Either the models are worth something or they aren’t. In this case it seems they aren’t.
See also:
The Mail On Sunday And The Met Office
by: Dr. David Whitehouse
I know of none climate models, which models AMO or PDO. Because in the very moment, the 1975-2005 warming trend would become a part of AMO. Models go stupidly up like CO2 curve and contain no natural variability, which is considerable.
North Atlantic: http://blog.sme.sk/blog/560/310249/Natlantic.jpg
North Pacific: http://blog.sme.sk/blog/560/310249/Npacific.jpg
Arctic: http://blog.sme.sk/blog/560/310249/arctic.jpg
Wayne2 says: October 16, 2012 at 4:26 am
“Nick Stokes: What’s the CI on that slope of 0.05 C/decade? And not just using the errors from the regression, but also using the uncertainty from the original data. I doubt that it’s statistically significant, and even if it is, it’s 1/4 what it’s supposed to be.”
I don’t think it is statistically significantly different from zero. It is difficult to get statistical significance for short time intervals. But that doesn’t mean that is is zero or less. It isn’t.
This post tries to make something of a statement from NOAA people that periods of fifteen years of zero trend are rarely observed with models in 21st Cen. Whether that actually applies to weather is arguable. But it doesn’t “put the kibosh” on anything, because the premise isn’t there. We haven’t observed 15 years of zero trend in 21st century.
If you want some fun looking at current weather stations around the World go to this site.
http://www.wunderground.com/wundermap/ If you dont see many stations hover your mouse pointer over the date at the top of the page to ‘Back Paddle’ 1 hour,another Tip is to uncheck the box in the right hand pane that says “Show personal weather stations” to avoid ‘overload’.
Have Fun.
Reblogged this on gottadobetterthanthis and commented:
As the narrative unravels, and the average persons starts to see that weather is and always has been fickle, the alarmists will grow more desperate. I think the facts are showing significance to the notion that humans only talk about the weather; they cannot really do anything about it. No warming observed means no warming. Besides, cold kills; warmer is better.
Mooloo
I’ve heard this claim before, but never seen a cite for it. can you corroborate anyone actually said that at the time?
If i’m reading the report right, they are referring to ENSO-adjusted trends. Removing the effect of ENSO (and solar influence) gives much warmer trends across all data sets for the most recent 15-year period, and the trends are statistically significant.
If I haven’t misread it, an apples to apples comparson would need to filter out the ENSO influence.
Nick Stokes:
I see that at October 16, 2012 at 5:34 am you attempt the same misdirection from both this thread’s subject and its importance as Dave Britton tried on behalf of the Met. Office at
http://metofficenews.wordpress.com/2012/10/14/met-office-in-the-media-14-october-2012/
So, I copy the answer I there gave to him.
Richard
Dave Britton:
You say,
What is “meaningful” depends on the meaning of interest.
The 1997 UN IPCC AR4 Report predicted (n.b. predicted not projected) that global temperature would rise over the first two decades after 2000 at an average rate of 0.2deg.C/decade +/-20%. This rise was certain because it was “committed warming” which the models said must occur as a result of anthropogenic GHG emissions already in the system.
The IPCC prediction can be seen at
http://www.ipcc.ch/publications_and_data/ar4/wg1/en/figure-10-4.html
In the graph the orange line represents the “committed” temperature increase the IPCC said would occur after 2000 if there were no additional CO2. Clearly, actual temps from 2000 until now are lower than the projected “committed” warming while CO2 levels have continued to rise.
There are only four possible meanings of the flat-line in global temperatures over the last 15 years; i.e.
1. The models are wrong.
Or
2. The global temperature estimates are wrong.
Or
3. Natural climate variation is sufficient to overwhelm anthropogenic warming.
Or
4. Some or all of the possibilities 1 to 3.
Richard
Please remember that the UK Met Office has to spin stuff in this way so that it fits the UK government’s commitment to decarbonisation. Publishing anything that cast doubt on the scientific basis and hence the rationality of the UK’s anti-carbon energy policy – now steered by Edward Davey to the course previously laid by Edward Miliband (demonstrating that on this occasion, two Eds are far, far worse than one) – would be as good as a letter of resignation from everyone involved.
The more I read the section, of which a portion is cited in the article above, the clearer it becomes that they are talking about trends with ENSO filtered out.
Does anyone parse that differently to me? Because it looks like using global temp trends without ENSO filtered out (as done in the top post) is an apples to oranges comparison, particularly considering the massive el Nino at the beginning of the period in question and the strong la Ninas at the end. This is going to to skew the trends considerably, making the comparison too suspect to be useful.
Can anyone gin up the ENSO-adjusted trends to make an apples to apples comparison?
Remember that email
From Phil Jones To John Christy
…If anything, I would like to see the climate change happen, so the science could be proved right, *regardless of the consequences.* This isn’t being political, it is being selfish. Cheers, Phil
@richard. I choose #1 first, then #3 second. You don’t need global temperature estimates to be wrong (then neither side could argue and that might even be worse).
Nick Stokes says:
October 16, 2012 at 5:34 am
We haven’t observed 15 years of zero trend in 21st century.
+++++++++++++
DUH! The 21st century is only 12 years.
Hard for normal people to get 15 years of trend out of 12 years of data. It takes a Real Climate Scientists to do that.
Question regarding the models:
Apparently the Met Office is claiming that the models do allow for some variation within the trend, attributing it to factors other than the level of CO2 in the atmosphere. My question is, do the models imply a return to the forecasted trend line over time, as one would expect? After all, if a given level of CO2 causes a given (modeled) temperature increase, but “other factors” disguise that increase for a time, then a return to the trend line at some point is implied. (Note that I’m specifying a return to the trend line, i.e., the forecast temperature level for a particular date, and not just a return to a trend rate of increase.)
But a return to the forecasted trend line following a 15-year period where temperature barely increases at all would imply a rapid increase in temperature sustained for some time thereafter, or alternatively a very rapid short term increase in temps. For that matter, if the models are correct, there should be a 50% probability of temperature exceeding the forecast temperature, so a return to trend could even (should even) result in an overshoot of the trend line.
Are the modelers confident enough in their models to claim that we should soon see a rapid acceleration of global temperatures so that the temperature levels forecasted by their models are reached, or even exceeded? After all, a given level of CO2 in the atmosphere is supposed to yield a certain temperature, as specified in their models. If they are not willing to claim a return to the trend line (not just a return to the forecast upward trend, but a return to the forecast trend line itself), then they are saying that they no longer believe their own models.
Ironically, if they continue to believe their models, the required warming to get them back on track becomes both larger, and more urgent, with each passing year of little or no increase, so they end up being required to forecast larger and larger near-term increases to return to modeled temperatures. If the models fail, they will thus fail spectacularly. A fair question to any modeler is “By what date do you expect the observed temperature to exceed your modeled temperature if your model is accurate?” (I use “exceed” as a reminder that the model forecasts a midpoint of expected temperatures and that, if correct, 50% of the time we should be experiencing temps above the model’s trend line.) The followup questions should be, “And to exceed that temperature by that date will require a minimum of how much warming per year from here on?”
Good questions, both, I think.
I’d been taking this quote as parsed here and other places before I wondered what Jones meant by ‘continue,’ so I looked up the emails.
http://foia2011.org/index.php?id=4149
Written in 2009 after a decade of little warming, Jones and Mike (Mann?) are discussing a trend continuing from the *present*. Mike estimates “10 more years of decline from now on
before it was really significant,” concurring with Jones, who said, “Bottom line – the no upward trend has to continue for a total of 15 years before we get worried. We’re really counting this from about 2004/5…”
So they are talking about a flat trend of about 22 years, not 15.
It’s very clear from the full text, and it has been misinterpreted all over the internet.
For a better perspective on T changes over the last 150 years, see
http://data.giss.nasa.gov/gistemp/graphs_v3/
One does not have to be a statistician to see a clear long term trend. By selective choice of any short term time span, one can get any short term trend one wishes to find – even a short term trend toward cooling.
The suggestion that the Earth has stopping warming is silly. Also there are other indicators of long term trends such as the disappearing glaciers in my back yard here in Glacier Park and the sea ice of the Arctic.
I believe that Gavin Schmidt also made comments a few years back on RealClimate that 15 years of no warming would be a problem for the climate models (initially he said 10 years but then changed it to 15).
The temperature trend for the lower troposphere is down for the last 16 yerars according to RSS:
http://www.woodfortrees.org/plot/rss/from:1997/to:2013/plot/rss/from:1997/to:2013/trend
ericgrimsrud:
At October 16, 2012 at 7:54 am you say
No! It is not a “suggestion”: it is reality according to all available data sets. To claim otherwise is silly.
Such a halt in global temperature change cannot continue indefinitely. Of interest is whether warming towards the global temperature of the Medieval Warm Period (MWP) will resume, or cooling towards the temperature of the Little Ice Age (LIA) will set in.
One can hope for the resumption of the warming with all its associated benefits, but should be worried at the possibility of the cooling with its associated horrors.
Richard
Check out rss data. It is flat for 16 years.
ericgrimsrud says:
October 16, 2012 at 7:54 am
You have been shown over and over that gistemp has been “adjusted” for specious reasons. You have been shown over and over that LST are compromised at data acquisition by UHI. You seem like a smart fellow. How come you are not absorbing any of this into your perspective?
Just a quick refresher on the damning emails;
http://drtimball.com/2012/classic-groupthink-behavior-apparently-exposed-in-leaked-cru-emails-2/
barry:
Even by your standards, your spin in your post at October 16, 2012 at 7:40 am is silly.
You say
No!
A “total of 15 years” means a total of 15 years, not 22.
Indeed, in his famous written interview with the BBC Jones said 15 years.
Richard
I am not sure why as skeptics we continue to entertain the Santer/Jones/Trenbath line that we need wait for 15 or 17 years to decide on a 95% confidence level to reject a hypothesis. That is sheer nonsense for the postulates of warming are not time related (other than the short time for an effect to show and the need for full year data to make like for like comparisons).
Hence it is not a time series that needs to be correlated but a T versus CO2 ppm level that needs to be satisfied as causally related. This is not a specific time element but comprised of the physics involved viz: does CO2 cause heating and hence T increase according to a Hansen type formula.
It is simply the difference in CO2 levels versus the change in T. Any reasonable CO2 difference is sufficient to dispel the hypothesis if it fails to show the required T increase. This has little to do with probabilities other than extreme defined events which mitigate and are shown to mitigate.
If it happens once we might tread lightly. Twice and it is almost damned. Three times and one can kiss the relationship goodbye. This is the only area in which the probabilities can assume meaning for there either is a physical causal effect or not.
Let me argue another way. If the CO2 hypothesis is reasonably correct then the only way that this hiatus of T increase can occur for any length of time while CO2 increases is if there are some mighty powerful mitigating factors at play which we don’t understand. Alternatively we would have to assume that CO2 behaves erratically and goes to sleep some of the time – and pigs also fly some of the time of their own accord. Either way this is part of the system and refutes the hypothesis.
My own sentiment is to keep hammering the clear violations like measurements (UHI – A. Watts, McIntyre) and the fact that all Hansen/model predictions have failed and thus falsify the hypothesis.
Getting too caught up in what their models say is counterproductive given that they have always failed. State it. Take it from the 1940’s and the alarmist hypothesis fails dismally.
In comments at Realclimate in 2007 where the latest plateau in temperatures was discussed Gavin Schmidt confirmed that he would be “worried about state of understandig” if 1998 was not dethroned as the record holder in _all_ temperature indices within 5 years. 1998 had already been dethroned by 2005 and 2007 in the GISS and NOAA indices at the time but 1998 was still the record holder in the RSS index as it is now. 5 years has gone by since then and no new record has been reached in the RSS index.
In comments Gavin confirmed this statement from a Daniel Klein: “If 1998 is not exceeded in all global temperature indices by 2013, you’ll be worried about state of understanding”
http://www.realclimate.org/?comments_popup=497#comment-78146x.
The trend has been mildly negative for the last 10 years:
http://www.woodfortrees.org/plot/wti/from:2002/to:2012/plot/wti/from:2002/to:2012/trend
Only after another 6 years of flat temperatures can we conclusively state that there was a 16 year period of no warming. Indeed, as Steve from Rockwood pointed out, a starting point just before or just after the 1998 El Nino peak would still leave us with a positive trend:
http://www.woodfortrees.org/plot/wti/from:1999/to:2012/plot/wti/from:1999/to:2012/trend
http://www.woodfortrees.org/plot/wti/from:1996/to:2012/plot/wti/from:1996/to:2012/trend