Via Tom Nelson: Dr. Michael Mann, author of The Hockey Stick and the Climate Wars, responds to last week’s attacks from Dr. Richard Muller.
On the Green Front – Dr. Joseph Romm and Dr. Michael Mann – 08/15/12 at On the Green Front
Mann at the 40:40 mark, bold mine:
“One of the more robust predictions is that in the Atlantic, hurricane intensities have increased and they will likely continue to increase, and so, it’s part of a trend, Katrina, the record season of 2005 was part of a trend towards more destructive storms…“
Umm. Mike, seen this?
Since Katrina, accumulated cyclone energy is (a measure of intensity) is down in the Atlantic and globally. Power dissipation is also down globally. Some trend there, huh Mike?
Graphs from Dr. Ryan Maue, source: http://policlimate.com/tropical/
Or, has Mike seen this?
On December 5th, 2011, Dr. Roger Pielke Jr. offered this graph of days between Cat3-5 hurricanes striking the USA:
Now, we are up to 2487 days since a major Hurricane made landfall on the USA. The graph looks like this now:
Where’s the trend toward more destructive storms Mike? Or are you reporting data from another planet?
UPDATE: For context, Mann is responding to a very critical interview with Richard Muller at the GREEN room. Full transcript of the Muller interview in the url below and write up at WUWT
@Izen: Nonsense. The global temperature record is real data and shows that temperatures have in fact been flat to declining since 2000 (http://www.drroyspencer.com/2012/02/uah-global-temperature-update-for-january-2012-0-09-deg-c/). Further, after a warmer than normal July for the United States, August is cooling quickly, which will negate any notions of 2012 being “the hottest summer on record.” All of this is even more significant if you believe the Keeling curve, showing a steady increase in CO2. It would seem the correlation between CO2 levels and temperature is tenuous, wouldn’t you say?
izen says:
August 17, 2012 at 7:08 am
Whether global temperatures have been flat since 2000 is open to dispute….
On all data sets, the different times for a slope that is flat for all practical purposes range from 10 years and 10 months to 15 years and 8 months. Following is the longest period of time (above 10 years) where each of the data sets is more or less flat. (*No slope is positive except UAH which is +0.0022 per year or +0.22/century up to July. So while it is not flat, the slope is not statistically significant either.)
1. UAH: since October 2001 or 10 years, 10 months (goes to July, but note * above)
2. GISS: since March 2001 or 11 years, 5 months (goes to July)
3. Combination of the above 4: since October 2000 or 11 years, 6 months (goes to March) (Hadcrut3 is SLOW!!)
4. HadCrut3: since January 1997 or 15 years, 3 months (goes to March) By the way, one has to back to the 1940s to find the previous time that a Hadcrut3 record was not beaten in 10 years or less.
5. Sea surface temperatures: since January 1997 or 15 years, 7 months (goes to July)
6. RSS: since December 1996 or 15 years, 8 months (goes to July)
RSS is 188/204 or 92.2% of the way to Santer’s 17 years.
7. Hadcrut4: since December 2000 or 11 years, 8 months (goes to July using GISS. See below.)
See the graph below to show it all for #1 to #6.
http://www.woodfortrees.org/plot/hadcrut3gl/from:1997/trend/plot/gistemp/from:2001.16/trend/plot/rss/from:1996.9/trend/plot/wti/from:2000.75/trend/plot/hadsst2gl/from:1997/trend/plot/uah/from:2001.75/trend
For #7: Hadcrut4 only goes to December 2010 so what I did was get the slope of GISS from December 2000 to the end of December 2010. Then I got the slope of GISS from December 2000 to the present. The DIFFERENCE in slope was that the slope was 0.0049 lower for the total period. The positive slope for Hadcrut4 was 0.0041 from December 2000. So IF Hadcrut4 were totally up to date, and IF it then were to trend like GISS, I conclude it would show no slope for at least 11 years and 8 months going back to December 2000. (By the way, doing the same thing with Hadcrut3 gives the same end result, but GISS comes out much sooner each month.) See:
http://www.woodfortrees.org/plot/hadcrut4gl/from:2000/to/plot/hadcrut4gl/from:2000.9/trend/plot/gistemp/from:2000/plot/gistemp/from:2000.9/to:2011/trend/plot/gistemp/from:2000.9/trend
@Izen–“The ENTIRE debate is about global warming, but this thread is about calling Mann wrong when he is right about N Atlantic intensity.” So, if Mann is correct about North Atlantic tropical storm intensity, and he may well be, what is the ultimate conclusion? Is he saying this is proof of global warming? Globally, storm intensity is down. Atlantic storms make up only 15% of tropical storm activity. If Mann is trying to draw a correlation between CO2 and Atlantic storm intensity, then he has his work cut out for him, as would anyone who seriously entertains such a theory.
Smokey There is no dispute. Temperatures have been flat since 2000, as shown in every metric.
To ‘prove’ his point Smokey plots a spaghetti graph of selected metrics from WoodForTrees. A strange mix of global and land-only datasets, he gives us the GISTEMP dtS land-only dataset, rather than the global Land-Ocean, the Northern Hemisphere CRUTEM 4, the global HadCRUT 3, but not the updated v4, etc. etc.
Here are some of the metrics Smokey doesn’t like. I am sure he has his reasons … http://www.woodfortrees.org/plot/gistemp/from:2000/plot/gistemp/from:2000/trend/plot/hadcrut4gl/from:2000/plot/hadcrut4gl/from:2000/trend/plot/crutem4vgl/from:2000/plot/crutem4vgl/from:2000/trend
Midwest Mark – eyeballing curves can play tricks – the same site allows you to calculate the least squares linear fit to the ‘real data’, for Dr Spencer’s UAH since 2000 it comes out at +0.11C / decade.
Phil Clarke,
Hadcrut3 was accurate, based on raw temperatures. Then it was ‘updated’ to a newly “adjusted” version 4 which – surprise – shows warming. So you’re just cherrypicking.
Don’t be so gullible. Here is the Hadcrut3 global mean. Notice that there is no warming trend; that only happened after the new “adjustment”.
Philip Bradley says:
August 16, 2012 at 7:06 pm
‘Robust’ refers to findings that can be easily replicated.
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Gunga Din says:
August 16, 2012 at 8:09 pm
I always thought “Robust” was what came out when I tried to type “Robert”. 😎
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I hate the word “Robust” when applied to science. It reminds me of a Snake-oil salesman trying to make a sale.
Duh. Typo: “When the frequency and severity of landfall storms etc.
increasesdecreases…”,