Unloading James Hansen's Climate Dice

Guest post by Chip Knappenberger, originally on Master Resource

“Today’s temperature ‘extremes’ are simply yesterday’s extremes warmed up a bit, partly from the heat-island effect. But they are not new events…. Hansen’s push on weather extremes is another case where the level of alarm is disproportionate to the level of impact.”  – Chip Knappenberger

Today’s temperature “extremes” are simply yesterday’s extremes warmed up a bit, partly from the heat-island effect. But they are not new events where none existed prior.

This distinction is neither subtle nor unimportant. When it comes to temperatures, yesterday’s extremes warmed up offer less of a surprise (and hence a greater ease of adaptability) than if a new crop of extreme events suddenly sprung up out of nowhere to catch us unprepared.

But such a distinction is not made prominently evident in the latest work by NASA’s James Hansen—and even less so in the accompanying media coverage (including that instigated by Hansen himself). Instead, the general audience is left with the distinct impression that anthropogenic global warming (as a result of greenhouse gas emissions from fossil fuel-based energy production) is leading to the occurrence of new extreme weather events when and where such weather events would not otherwise have occurred. For instance, in a Washington Post op-ed written by Hansen to accompany the release of his paper recently published in the Proceedings of the National Academy of Sciences, Hansen writes:

Our analysis shows that it is no longer enough to say that global warming will increase the likelihood of extreme weather and to repeat the caveat that no individual weather event can be directly linked to climate change. To the contrary, our analysis shows that, for the extreme hot weather of the recent past, there is virtually no explanation other than climate change.

The deadly European heat wave of 2003, the fiery Russian heat wave of 2010 and catastrophic droughts in Texas and Oklahoma last year can each be attributed to climate change. And once the data are gathered in a few weeks’ time, it’s likely that the same will be true for the extremely hot summer the United States is suffering through right now.

But this impression is untrue. These events and others like them, almost certainly would have occurred on their own (i.e., naturally). Climate change may have added a pinch of additional heat, but it almost certainly did not create these events out of thin air (see here for example).

But Hansen pushes this impression with his analogy of “Climate Dice.” The idea is that anthropogenic greenhouse gas emissions have “loaded” the dice towards extreme warmth, so now when Mother Nature rolls the dice for summer weather, there is better chance of rolling a heat wave, or an overall hot summer—events discreet from events that were contained on the unloaded dice.

But Hansen’s hot summers are not new discrete events at all. Instead, they are the naturally occurring hot summers with a few extra degrees added to them. The extra couple of degrees push some summers over an arbitrarily defined threshold temperature above which Hansen classifies them as being “extreme.”

Hansen’s threshold between a “normal” summer and an “extreme” summer has no physical meaning—instead it is rooted in statistics. While certainly some temperature thresholds exist that have physical meaning—like the 32°F, the freezing/melting point of water/ice—none exist in the range of temperatures which characterize summer across much of the globe. Whether or not the average summertime temperature is greater or less than some arbitrary value is of little practical significance.

Washington, D.C. Example

Let’s take the nation’s capital as an example. The mean summer (June through August) temperature in DC during the 30 year “base” period used by Hansen (1951-1980) was 77.0°F. The standard deviation—a statistical measure of the amount of year-to-year variability that exists about the average—was 1.2°F. Statistically, 67% of all values lie within one standard deviation of the mean.

For Washington DC, it means that 2/3rds of summers between 1951 and 1980 should have had an average temperature between 75.8°F and 78.2°F. Again, statistically speaking, 95% of all average summer temperatures should lie within two standard deviations, or between 74.6°F and 79.4°F. And less than one-half of 1% of all summer average temperatures should lie outside three standard deviations from the mean.

Hansen defines an “extreme” summer as one that is hotter than 3 standard deviations above the mean. So, for Washington DC that would mean a summer with an average temperature greater than 80.6°F—a situation that would almost never occur in the climate of 1951-1980 in DC.

Now let’s fast forward to the climate of the most recent 30 years. During the period from 1983-2012, the average summer temperature was 78.0°F—a full degree higher than it was during the base period. And, two summers (2009 and 2010) exceeded 80.6°F (that is, were more than 3 standard deviations above the 1951-1980 average). By Hansen’s reckoning, these were global warming induced climate “extremes.”

But are these hot summers entirely caused by global warming (or rather, climate change)?

If we went back and added 1°F to each summer from 1951 to 1980, one of them would have exceeded three standard deviations, and several others would have been close. In other words, the current climate of DC is pretty similar to the past climate of DC, just warmed up a bit. It is not a completely new climate replete with a different array of extreme events conjured up by human greenhouse gas emissions.

So yes, it is true that summers in DC are hotter than they once were. But local land-use changes (the increased heat-island effect) are largely to blame.

Compared to past climates, more summers now meet Hansen’s arbitrary definition of being “extremely” hot. But climate warming is not responsible for all the heat, instead it just adds some warmth to what would have been a hot summer anyway.

Certainly, the hotter it is in DC, the more air conditioners run and other costs incur as well. And quite possibly, the costs increase in some non-linear fashion (see here for a discussion). But, it is almost certain as well that the costs do not rise anywhere near as swiftly as the tally of events crossing some arbitrary threshold by which to define and “extreme” event.

Hansen’s push on weather extremes is another case where the level of alarm is disproportionate to the level of impact.

Addendum:

John Christy took a further look at the occurrences of weather extremes, as well as how Hansen’s recent analysis does not fairly represent them, in testimony last week before the House Energy and Power Subcommittee. It is worth checking out (see here).

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HaroldW

It looks like you’re attributing the italicized passages which lead off the article to Hansen, but they are Knappenberger’s. [First & last sentences.]

KevinM

Is that quote criticising Hansen’s work attributed correctly?

Steven Hill

Hasen told us another Ice Age was coming in 1977, enough said for his credibilty.

Nothing new about extremes at high phase of the AMO
http://www.vukcevic.talktalk.net/AMO-T.htm

Bill

You quote Hansen quoting himself and saying he is wrong??? Very first paragraph needs to be fixed (sets off alarm bells)

JohnH

Can we have some Golbull Warming in the UK please next summer, seems it missed us out this summer and what we got was not pleasant !!!!!

KevinM

The lead quote is actually from Chip Knappenberger, not Hansen.

So… Hansen describes “extreme” as being 3 standard deviations away from the mean. I guess stuff in that realm would be indicative of something very very wrong, that was in dire need of attention.
The mean of the rate of Executive decree, is 6.39 decrees/year with a sigma of 39.7. (all Presidents). Does that make the current Presidents rate of decree, at 263 per year, alarming and in dire need of attention? The Z-Score is only 6.48…

cui bono

Thanks for the post Chip.
Just to clarify, are you saying Hansen is calculating todays 3sd events based on deviations from the average of a cooler era?
Like, if we calculated todays Summers vs. the Little Ice Age, we’re all doomed?
And isn’t that, um, slightly misleading on Hansen’s part?

Chip: The opening quote needs to have a new attribution – Hansen would not state:”Hansen’s push….” The original quote (at Master Resource) has no attribution at all.

knots340

A 30 year base period 9only 30 samples in the data set0 would probably not supply a reasonable value for the standard deviation. I would think at least a hundred samples, or even better, a 1000 samples. Then the sigma computed from that data set would give a better indication of the natural variability. In that case, even the so-called 2009, 2010 3-sigma “outliers”, may not even be outliers at all with a more complete data set.

AlecM

But because the real GHE is thermal emission from the atmosphere reducing surface emissivity in GHG wavelength bands, standard radiative physics known to professional engineers around the World, there can be no CO2-AGW or positive feedback.

commieBob

The following poem applies well to the work of James (Jack) Hansen.

from the collection “Space Child’s Mother Goose” by Frederick Winsor and Marian
Parry (Simon and Schuster, 1956)
This is the Theory Jack built. This is the Flaw That lay in the Theory Jack built. This is the Mummery Hiding the Flaw That lay in the Theory that Jack built. This is the Summary Based on the Mummery Hiding the Flaw That lay in the Theory that Jack built. This is the Constant K That saved the Summary Based on the Mummery Hiding the Flaw That lay in the Theory that Jack built. This is the Erudite Verbal Haze Cloaking Constant K That saved the Summary Based on the Mummery Hiding the Flaw That lay in the Theory that Jack built. This is the Turn of a Plausible Phrase That thickened the Erudite Verbal Haze Cloaking Constant K That saved the Summary Based on the Mummery Hiding the Flaw That lay in the Theory that Jack built. This is the Chaotic Confusion and Bluff That hung on the Turn of a Plausible Phrase That Thickened the Erudite Verbal Haze Cloaking Constant K That saved the Summary Based on the Mummery Hiding the Flaw That lay in the Theory that Jack built. This is the Cybernetics and Stuff That covered Chaotic Confusion and Bluff That hung on the Turn of a Plausible Phrase That thickened the Erudite Verbal Haze Cloaking Constant K That saved the Summary
Based on the Mummery Hiding the Flaw That lay in the Theory that Jack built. This is the button to Start the Machine To make with the Cybernetics and Stuff To cover Chaotic Confusion and Bluff That hung on the Turn of a Plausible Phrase That thickened the Erudite Verbal Haze Cloaking Constant K That saved the Summary Based on the Mummery Hiding the Flaw That lay in the Theory that Jack built.
This is the Space Child with Brow Serene Who Pushed the Button to Start the Machine That made with the Cybernetics and Stuff Without Confusion, exposing the Bluff That hung on the Turn of a Plausible Phrase And, shredding the Erudite Verbal Haze Cloaking Constant K Wrecked the Summary Based on Mummery Hiding the Flaw And Demolished the Theory that Jack built.

All the line breaks are removed so the poem fits in a reasonable space.

son of mulder

Would UHI affect Tmin and Tmax individually in the same way as AGW theory? If not then there must be someone out there able to mathematically demonstrate which process is dominating the record temperature periods.

John Peter

I would be more interested in seeing a comparison with say 1931-1960 using original data rather than the GISS adjusted temperatures. Picking the “cold” period around 1970 is just such an old trick by the “Hansen” types of this world.

Betapug

Has anyone calculated the contribution to the rise in the Washington DC area oudoor temperature from aircon pumping heat from indoors to outdoors?

John Garrett

If you’ve been living near the “Mistake On The Potomac” for the past sixty-odd years, you’d have witnessed the colossal growth of concrete and the destruction of farmland— all due to the cancerous growth of government.
The development, urban sprawl and the hordes of immigrants (domestic and foreign) feeding at the government trough have wrecked what was once a pleasant place to live.
I’d like to ship the lot of ’em to Pocatello or Couer d’Alene or Ogden. That would solve a big part of the area’s “catastrophic anthropogenic global warming” problem.

MarkW

In my opinion, 30 years is way to short a period to be taking as any kind of definition of normal.
At an absolute minimum, it should be extended to 60 years to at least cover both halves of the PDO.

Gamecock

Hansen: “there is virtually no explanation other than climate change”
Argumentum ad ignorantiam. That he has no other explanation does not make his explanation valid.

Rob Bradley

Right–the opening quotation is from Chip’s post quoting himself, not Hansen.
– Rob Bradley (MasterResource)

oldseadog

Dr. Christy’s evidence to the House Subcommittee is pretty devastating.
It would be interesting to have a reaction from the warmist team, and even more interesting to have a proper resume in the MSM.
Not holding my breath, though.

Jack Linard

This is unacceptable. No thinking person would read past the first paragraph which is blatantly wrong and foolish.

highflight56433

Temperature extremes include both the high and the low; so why do we only see discussion about highs?

GoWhitecaps!!!

Hansen cherry picks hot temperature to explain his extreme weather events conveniently ignoring the current hurricanes, tornados, and cold extremes in the UK.

manicbeancounter

There is a further caveat to add to Hansen’s argument to turn it from being a trivial observation of extreme weather, to be a signal of a coming climate catastrophe that can justify current policy. The extreme weather must be significantly more costly, whether it be purely financial, the cause of human suffering, or endangering the general flora and fauna. My mother comes from the far North of Scotland, where the record highest temperature is less than 77F. A few degrees more would be beneficial.

Kev-in-Uk

knots340 says:
October 1, 2012 at 9:33 am
absolutely – which is exactly why they ‘pick’ a small base year period – when in reality, many more data points would be needed just to identify the natural variation, let alone any alleged AGW. Of course, we KNOW there is a UHI effect, and we KNOW this has happened increasingly in the modern era, but of course UHI is not AGW! – so only (top quality) rural stations should be used for any meaningful trend analysis.

highflight56433

“there is virtually no explanation other than climate change”
I really do not see how a change up or down can be “climate change.”
Climate refers to the air mass or masses typical to a location; it is tropical, or continental or marine, or whatever. Changes in temperature do not make for climate change.

David, UK

“Hansen’s push on weather extremes is another case where the level of alarm is disproportionate to the level of impact.” – Dr. James Hansen, NASA GISS
Wishful thinking to suppose that Hansen would undergo such self-analysis. An attribution correction is in order methinks!

“John Garrett says:
October 1, 2012 at 10:11 am
If you’ve been living near the “Mistake On The Potomac” for the past sixty-odd years, you’d have witnessed the colossal growth of concrete and the destruction of farmland— all due to the cancerous growth of government.
The development, urban sprawl and the hordes of immigrants (domestic and foreign) feeding at the government trough have wrecked what was once a pleasant place to live.
I’d like to ship the lot of ‘em to Pocatello or Couer d’Alene or Ogden. That would solve a big part of the area’s “catastrophic anthropogenic global warming” problem.”

What’s wrong with sending them to the Maldives or Bangladesh? No reason to keep them all for ourselves. Let’s send them where they can see the meters the ocean isn’t rising.

Thomas T.

“Hasen told us another Ice Age was coming in 1977, enough said for his credibilty.”
He said no such thing.
[Reply: Article corrected. The quote was by Chip Knappenberger, not James Hansen. — mod.]

Crispin in Johannesburg

Bitterly cold winter is over in Johannesburg. It is the peak of the wet end of the summer rainfall region’s 18.7 year drought cycle. Next ‘unprecedented’ drought will be in 2021.
Remember when a storm would be a ‘200 year’ event? That was an implicit recognition that these events occur now and then.

AndyG55

JohnH says:
Can we have some Golbull Warming in the UK please next summer, seems it missed us out this summer and what we got was not pleasant !!!!!
I hope I’m wrong, but I have a bad feeling that this coming winter will be far worse up there
Good luck.

Kelvin Vaughan

JohnH says:
October 1, 2012 at 8:48 am
Can we have some Golbull Warming in the UK please next summer, seems it missed us out this summer and what we got was not pleasant !!!!!
Did you mean gullable warming?

Kelvin Vaughan

Betapug says:
October 1, 2012 at 9:58 am
Has anyone calculated the contribution to the rise in the Washington DC area outdoor temperature from aircon pumping heat from indoors to outdoors?
And from traffic and planes.
In a temperature inversion hot air falls!
Oh and big cities are now microwave ovens caused by microwave communications.

D.M.

Chip,
Your comments regarding the fraction of observations falling within 1, 2 and 3 sd only holds true if the summer time temperatures are normally distributed. Are they? Can you post a link to your data or data source please?

Thomas T. says:
“Hasen told us another Ice Age was coming in 1977, enough said for his credibilty.”
He said no such thing.
………………………………………………………………..
Fair enough.
The scientist was S.I.Rasool, a colleague of Mr. Hansen’s at the National Aeronautics and Space Administration. Hansen was part of the consensus view that another Ice Age was on the way.

Thomas T.

“Hansen was part of the consensus view that another Ice Age was on the way.”
That is incorrect. If there was a consensus view in the 1970’s, it was global warming, including Hansen. For a review of the 1970s literature see:
Peterson et al. Bulletin of the American Meteorological Society 89:1325-1337 (2008)
Particularly Fig. 1, from the Figure Legend: “During the period from 1965 through 1979, our literature survey found 7 cooling, 20 neutral, and 44 warming papers.”
That is, over 6 fold more papers citing warming.

D Böehm

Thomas T says:
“…over 6 fold more papers citing warming.”
Not really. 27 papers cited neutral or cooling, vs 44 citing warming. Anyway, there are literally thousands of climate related papers out now, and probably hundreds more are published every year. Forty four papers over a decade was nothing. Now the big bucks are in the global warming scare, so every author is obliged to have a comment relating to ‘climate change’ if at all possible.
I got out of the military in the early ’70’s, and I clearly recall the global cooling scare. It was regularly on the TV news, it was in the newspapers, on radio, in magazines; the global cooling false alarm was being sounded everywhere. Scientists were being interviewed and quoted. Maybe one of them talked about global warming, but I never heard it. It was all cooling all the time.
Maybe you’re too young to remember. But it was the mirror image of today’s global warming scare.

P. Solar

Hansen seems to think his trick with the air-con before giving testimony to congressional committee was quite clever. Why should we believe he is not still engaged in the same kind of deception every time he speaks?
That’s not a provocative statement, it is a simple, flat, impassionate question. He seems to honestly believe he is part of some crusade where the ends justify the means. Why should be believe anything he says?
What is more telling is why , well past retirement age, he is allowed to carry on such a deception while waving the NASA banner.

D. Boehm –
I remember the cooling scare too. It’s interesting that the warming scare is coming from the same people who brought us the cooling scare. It says infinitely more about the sick psychology and venality of scaremongering than it does about climate.
On another point – we skeptics need to find a way to force the CRL-controlled news media and academic journals to publish information contrary to their ideological claptrap.
Also, I believe we can get our message across to the public very easily, by pointing out the simple ways to disprove AGW. Any layman can follow a discussion of animal respiration, or an honest graph showing the decline of temperatures since 1998, or showing the non-correlation of CO2 to temperatures. You don’t have to be a degreed scientist or even a college graduate to understand these things and draw the correct conclusions.

jorgekafkazar

commieBob says: “The following poem applies well to the work of James (Jack) Hansen. — from the collection “Space Child’s Mother Goose” by Frederick Winsor and Marian Parry (Simon and Schuster, 1956):
This is the Theory Jack built…
Excellent; very apropos. If only we had that button to push…

DJ

Would someone care to look at the effects of air conditioning D.C.??
While the air conditioned building (or car?) is cool on the inside during one of these summers, it is pumping the interior energy to the outside as heat. That would seem a net zero, but for the fact that the AC unit itself is not 100% efficient. Each AC unit then is, as far as the outside atmosphere goes, is a heater, receiving it’s energy from some distant power plant.
What then is the heat load imposed on D.C. by the air conditioning units, certainly more prevalent now than they were in the ’50’s? Cooler now on the inside, at the expense of warmer now on the outside…. oh, physics.

HaroldW

P.Solar: “Hansen seems to think his trick with the air-con before giving testimony to congressional committee was quite clever.”
You can’t blame Hansen for that. It was the idea of Sen. Tim Wirth. See http://www.pbs.org/wgbh/pages/frontline/hotpolitics/interviews/wirth.html

D Böehm

Chad Wozniak,
Actually, there is a correlation between ΔT and ΔCO2. But it is the opposite of what the alarmists claim. The chart shows clearly that temperature changes cause CO2 changes. There are no evidence-based charts showing that changes in CO2 cause changes in temperature.

Richard M

IIRC, Hansen wrote one of the first climate computer models and that model “predicted” global cooling. Are some folks trying to rewrite history?

kbray in california

Global Warming may be contagious.
Mars is having unusual warmth:
http://www.space.com/17828-mars-weather-curiosity-rover-discovery.html
Those pesky Martians must be making more co2…
It’s MGW… Martianogenic Global Warming !

Wayne2

Actually, I’m working on a paper to properly eviscerate Hansen’s paper.
As you note, he shows that if it’s a bit warmer on average, it will tend to be a bit warmer. He does this with a wall of text, graphs, and data that obscures what he’s doing so that you might get the impression that things are an order of magnitude worse than it used to be, and that things are more variable than they used to be.
In the paper, and an online followup, he also pulls tricks regarding his baseline period. Skeptics pointed out to him that the Dustbowl Years were pretty extreme, too, so he rolled the 1920-1950 timeframe into his baseline and said, “See, I still have a point!” The problem is he should have actually treated the 1920-1950 period separately so that he’d be able to distinguish two scenarios: a) the 1951-1980 period is normal, and the 1981-2011 period is more extreme, and b) the 1981-2011 period is normal and the 1951-1980 period is unusually quiescent. Turns out that it’s option b.

Paul Milenkovic

My subjective impression was that there was a Pending Ice Age scare in the late 1970’s, it was “driven” by the temperature records, and it was regarded as the kind of science scare mongering as worrying about an asteroid impact or the Yellowstone Volcano.
There was a fear of CO2-driven warming, but I don’t think it came from the temperature-monitoring people — I think it came from computer model people. I remember being on the Caltech campus in the year 1980 and having a sidewalk conversation with a man doing computer model work, he was very earnest about CO2 warming being the problem, and he was mad at people for not taking nuclear power more seriously.
I regard nuclear power as a touchstone for a person taking CO2 warming seriously. If CO2 is really that much of a problem, you don’t muck around with photovoltaics and carbon trading, and some First Worlders traipsing to some international conference on a jet, salving their conscience by purchasing a carbon offset by having regiments of Third Worlders lift their water with leg-driven instead of Diesel pumps. Were CO2 taken seriously as an emergency, one would go all out in a crash program to develop nuclear power. And there are people who take CO2 seriously, and they are serious about nuclear power, as was my acquaintance at Caltech some 30 years ago.
I wish I remembered the man’s name, because the people sounding the alarm on CO2 in 1980 based on computer models may have been a small community. Maybe the bibliographic search engines could turn up who at Caltech was publishing on climate models at that time?

Arno Arrak

I looked up the original article and found some interesting correlations. He says in the abstract that distribution of seasonal mean temperature anomalies has shifted towards higher temperatures and the range of anomalies has increased. I went looking for it. Unfortunately the paper is laden with pretty worthless illustrations, among them almost thirty multi-colored world maps that can best be described as objects suitable for administering a Rohrschah test. There is also a plethora of graphs plus nine anomaly distributions organized by climatology. The data that I was looking for surely had to be contained in those distributions and by luck it was. I say by luck because he tried various ways of displaying data until he hit upon the idea of normalizing the area under the curves. The graph I found most useful was the one in his Figure 9 that uses climatology from 1951 to 1980. This is a good baseline choice because temperature was pretty much constant during that time. He also shows other baselines that make a jumble of it and are impossible to interpret. Each graph shows data for six decades, color coded so you can distinguish them. The width of each decadal graph is determined by the anomaly distribution during the decade. According to Hansen the anomaly range increases with temperature but his graphs do not show temperature. Even more important is to be able to compare decade-to-decade broadenings as they relate to temperature. On the graph I chose the first three decadal distributions (1951-1961, 1961-1971 and 1971-1981) fall quite accurately on top of each other. This is exactly what I would expect because we know that there was no temperature change then. There was no warming in the fifties, sixties, and seventies and people then were worried about a coming new ice age, not global warming. The next graph up, for 1981-1991 (light blue), is slightly shifted and broadened. In1976 there was that “great Pacific climate change” which is supposed to have raised global temperature stepwise and it is possible that this slight temperature rise may have an influence on that particular anomaly distribution. The next decade is 1991-2001 (dark blue) and shows even more broadening. This decade includes the super El Nino of 1998 which surely raised the overall temperature enough to be the cause of that broader anomaly distribution. And last, but not least, is the decade of 2001-2011 (purple). It is very noticeably broadened, more so than any distribution that preceded it. This clearly correlates with the fact that this was also the record warm first decade of our century. From all this we can say that yes, warmer global temperature does lead to a broader anomaly distribution if these data are correct. But this is history and it tells us nothing about future temperature change. At the present time, there is no warming and there has not been any since the beginning of the twenty-first century. Nevertheless, IPCC AR4 has predicted that greenhouse warming in the twenty-first century will proceed at the rate of 0.2 degrees Celsius per decade. We are now in the second decade of this century and there is no sign of this predicted warming. IPCC prediction was made using the greenhouse theory of warming and has turned out to be false. In science, if a theory makes a prediction and the prediction is wrong the theory itself is also considered wrong and must be abandoned. The greenhouse theory of IPCC has made such a wrong prediction and must be abandoned. And with it the hypothesis of anthropogenic greenhouse warming. AGW rest in peace.

highflight56433 says:
October 1, 2012 at 12:11 pm
Climate refers to the air mass or masses typical to a location; it is tropical, or continental or marine, or whatever. Changes in temperature do not make for climate change.
=======
good point. Has the climate actually changed in Washington DC? Or is it pretty much like it has been for the past 8000 years? Once you get past the hundreds of square miles of pavement and concrete that has replaced the natural vegetation. Not that that would have any effect.