Guest post by Steve Goddard
Archimedes had his eureka moment while sitting in the bathtub. Newton made a great discovery sitting under an apple tree. Szilárd discovered nuclear fission while sitting at a red light.
There was a time when observation was considered an important part of science. Climate science has gone the opposite direction, with key players rejecting observation when reality disagrees with computer models and statistics. Well known examples include making the MWP disappear, and claiming that temperatures continue to rise according to IPCC projections – in spite of all evidence to the contrary.
Here is a simple exercise to demonstrate how absurd this has become. Suppose you are in a geography class and are asked to measure the height of one of the hills in the Appalachian Plateau Cross Section below.
Image from Dr. Robert Whisonant, Department of Geology, Radford University
How would you go about doing it? You would visually identify the lowest point in the adjacent valley, the highest point on the hill, and subtract the difference. Dividing that by the horizontal distance between those two points would give you the average slope. However, some in the climate science community would argue that is “cherry picking” the data.
They might argue that the average slope across the plateau is zero, therefore there are no hills.
Or they might argue that the average slope across the entire graph is negative, so the cross section represents only a downwards slope. Both interpretations are ridiculous. One could just as easily say that there are no mountains on earth, because the average slope of the earth’s surface is flat.
Now lets apply the same logic to the graph of Northern Hemisphere snow cover.
It is abundantly clear that there are “peaks” on the left and right side of the graph, and that there is a “valley” in the middle. It is abundantly clear that there is a “hill” from 1989-2010. Can we infer that snow cover will continue to increase? Of course not. But it is ridiculous to claim that snow extent has not risen since 1989, based on the logic that the linear trend from 1967-2010 is neutral. It is an abuse of statistics, defies the scientific method, and is a perversion of what science is supposed to be.
Tamino objects to the graph below because it has “less than 90% confidence” using his self-concocted “cherry picking” analysis.
So what is wrong with his analysis? Firstly, 85% would be a pretty good number for betting. A good gambler would bet on 55%. Secondly, the confidence number is used for predicting future trends. There is 100% confidence that the trend from 1989-2010 is upwards. He is simply attempting to obfuscate the obvious fact that the climate models were wrong.
Science is for everyone, not just the elite who collect government grant money. I’m tired of my children’s science education being controlled by people with a political agenda.
Ron Broberg,
You continue to be confused – and you demonstrate the point of this article. There is absolutely no question that snow extent has increased over the last 20 years.
http://wattsupwiththat.files.wordpress.com/2010/02/north_american_winter_dec-feb_snow_extent_1989-2010.png?w=510&h=312
http://wattsupwiththat.files.wordpress.com/2010/02/dec-feb_snow_ext.png
However, people who claim that there is a physical relationship between increasing CO2 and increasing temperature have to demonstrate this over all time periods, not just the last twenty years.
My claim is that Northern Hemisphere and North American snowfall have increased for the past twenty years, and they unequivocally have. If think that I am incorrect, and that the current record maximum is an artifact of bad analysis, then good luck with that.
ginckgo,
You have made the key point “CO2 is more effective a GHG at low concentrations”
Exactly correct. The first 30 ppm create the vast majority of CO2 warming. That is why further increases in CO2 have less and less impact on temperature. Which is the opposite of a tipping point.
Your argument about different continent location, etc. is spurious. Regardless of the shape, location, etc. of the continents – temperature should still follow CO2 according to promoters of catastrophic climate change. The absolute value may change but not the relative relationship.
Steve Goddard (21:06:47) :
Here is another widely used one which shows even less correlation.
If the two Figures show different amounts of correlation, then it seems likely to me that the Figures are faulty to begin with. Depending on what one wants to show, one can then [cherry] pick the one that fits the best, as you apparently did.
Now, where is [9th time] the overplot of the snow cover on the models predictions?
Ron,
Let me turn this around. Tamino claims (based on his statistical analysis) that winter snow extent has not increased over the last twenty years. This is his graph.
http://go2.wordpress.com/?id=725X1342&site=tamino.wordpress.com&url=http%3A%2F%2Ftamino.files.wordpress.com%2F2010%2F02%2Fsince89.jpg
Is he correct, or has winter snow extent increased? Do you think that winter snow extent has increased over the last twenty years?
Leif,
Find the raw data for the prediction graphs if you want to see a comparison. The images in the article are much too low resolution to make an overlay.
There was an ice age in the Ordovician with CO2 levels about 10-20X current. All of the graphs show that.
Steve: Do you think that winter snow extent has increased over the last twenty years?
(Assuming negligible measurement errors …)
As I stated above, it is a fact that snow extant in Jan 2010 is greater than in Jan 1988.
What I am curious about is that straight line you drew, that trend I want to know if it is statistically significant. If it is, then there is likely an underlying climatic mechanism which is driving increasing snow extant. If the trend is not statistically significant, then the fact that snow extant is greater in 2010 than in 1988 is just random noise – significant of nothing.
Now you don’t need a statistically significant increasing snow trend to analyze the skill in the models you quoted in an earlier post. Those models predicted a declining trend. In essence, you could reverse the analysis that is being done for temperature anamolies and the IPCC. See the following links:
Chad @ur momisugly Wood For Trees
AR4 Model Hypothesis Tests
Lucia @ur momisugly The Blackboard
Multi-Model Mean Projection Rejects: GISSTemp, start dates ‘50, ‘60, ‘70, ‘80.
HadCrut Compared to IPCC Simulations Ending Dec. 2009.
Tamino @ur momisugly Open Mind
Models
Nick @ur momisugly Moyhu
Testing the performance of GCM models
Steve Goddard (06:17:29) :
Find the raw data for the prediction graphs if you want to see a comparison. The images in the article are much too low resolution to make an overlay.
If the eye can tell the difference an overlay is possible. I’ll make one for you, then.
There was an ice age in the Ordovician with CO2 levels about 10-20X current. All of the graphs show that.
Milankovic and Plate Tectonics beat CO2 most of the time. That’s why one must exclude those sharp dips from the comparison.
“Reverse the analysis” is poor phrasing.
Try instead, ‘analyze the predicted declining trend’
Steve Goddard (06:12:18) :
Let me turn this around. Tamino claims (based on his statistical analysis) that winter snow extent has not increased over the last twenty years. This is his graph…
I have a problem with his graph [and a bit with yours too]. It concerns 2010. He sets it to 49 million, you have it at somewhere above 48 million. When I add up the Rudgers data I get 47.740 for the 2010 winter, through week 7.
Leif,
Here is an overlay of predicted vs. actual winter Northern hemisphere snow cover. It is difficult getting the axes scaled identically at that resolution, but they are close.
http://docs.google.com/View?id=ddw82wws_424d5kpssgb
Steve Goddard (07:14:46) :
Here is an overlay of predicted vs. actual winter Northern hemisphere snow cover.
No, that is North American snow cover, not hemispheric. And why start in 1989. Show all of the data. And on the full scale plot that you showed long ago of the models.
Leif,
The average latitude of land during the Ordovician ice age wasn’t hugely different than it is now. The main difference is that land was mainly centered around the South Pole, whereas now it is mainly centered around North Pole (except for Antarctica)
Steve Goddard (07:21:50) :
The average latitude of land during the Ordovician ice age wasn’t hugely different than it is now.
And that is why we have an ice age now and had one back then too.
Leif,
The climate model predictions were for North America (remember?) That is why I overlaid North America snow on top of them. The last twenty years were when the decline was supposed to happen. That is why I used the last 20 years of data.
Leif,
C)2 levels were 10-20X higher during the Ordovician. Ice age does not equal runaway global warming.
Ron,
My point is that Tamino spent a lot of time doing statistical analysis, and came up with the wrong answer about the behaviour of winter snow over the last 20 years.
I have absolutely no idea what is causing all the snow the last few years. But it is happening. I also have no idea if it will continue. I’m just making observations.
Leif,
Some might disagree with your assertion that we are currently having an ice age.
Leif Svalgaard (11:35:10) :
Thankyou, I can now see that you are incapable of telling the TRUTH where this subject is concerned.
The trick of finding 3 out of 20 years to prove a counterpoint is typical.
Steve Goddard (07:31:47) :
The climate model predictions were for North America (remember?)
Yet, in your post on this you compared the models to the hemispheric data (remember). You possibly did that because the ‘increase’ was more systematic for the whole hemisphere.
The last twenty years were when the decline was supposed to happen. That is why I used the last 20 years of data.
Some of the models showed a decline long before that.
To do a valid analysis you simply plot all the data for the same area on the same graph without cutting and selecting.
Steve Goddard (07:42:27) :
Some might disagree with your assertion that we are currently having an ice age.
That’s because they don’t know their stuff. We are in an ice age which has lasted several million years and will probably continue so for perhaps the same amount of time. During Ice Ages several glaciations occur controlled by orbital changes [that always occur]. There are interglacials between the glaciations. We live near the end of one of those interglacials. For an ice age to occur something else [land distribution, ocean straights, volcanism, whatever] must set the stage for Milankovic to work.
A C Osborn (07:45:04) :
the TRUTH where this subject is concerned.
A [civil] court case is not about truth, but about redressing alleged wrongs.
Leif,
North America is part of the Northern Hemisphere, but in the article I used the entire Northern Hemisphere because it made it more clear that this is not a local trend. In fact, the North American trend is even strongly upwards than the rest of the hemisphere.
A C Osborn (07:45:04) :
The trick of finding 3 out of 20 years to prove a counterpoint is typical.
First, your questions would not be allowed in court since all data has already been presented. The standard objection is ‘asked and answered’. This objection is usually sustained, because otherwise the questions would amount to leading the witness [and rhetorically influencing the jury].
Second, the upward trend is based on just three years. Remove 2003, 2008, and [the incomplete] 2010 and you have nothing.
Leif,
Seven out of the last ten years have been above 45 million km2, and eight out of the previous eleven were below 45 million km2. That is an upwards trend, ?que no? Speaking of statistics, that is a several sigma event.
Steve Goddard (08:36:40) :
North America is part of the Northern Hemisphere, but in the article I used the entire Northern Hemisphere because it made it more clear that this is not a local trend.
The models were only about N.A. and do not claim they show a global trend. For valid analysis you compare apples and apples.
In fact, the North American trend is even strongly upwards than the rest of the hemisphere.
The N.A. data is even more reliant on a single [incomplete] data point, 2010, so its significance is less.