Now IPCC hurricane data is questioned

[FarCenter]

http://www.theregister.co.uk/2010/02/15/hatton_on_hurricanes/
By Andrew Orlowski • 15th February 2010 11:00 GMT

More trouble looms for the IPCC. The body may need to revise statements made in its Fourth Assessment Report on hurricanes and global warming. A statistical analysis of the raw data shows that the claims that global hurricane activity has increased cannot be supported.

Les Hatton once fixed weather models at the Met Office. Having studied Maths at Cambridge, he completed his PhD as metereologist: his PhD was the study of tornadoes and waterspouts. He's a fellow of the Royal Meterological Society, currently teaches at the University of Kingston, and is well known in the software engineering community - his studies include critical systems analysis.

Hatton has released what he describes as an 'A-level' statistical analysis, which tests six IPCC statements against raw data from the National Oceanic and Atmospheric (NOAA) Administration. He's published all the raw data and invites criticism, but warns he is neither "a warmist nor a denialist", but a scientist.

Hatton performed a z-test statistical analysis of the period 1999-2009 against 1946-2009 to test the six conclusions. He also ran the data ending with what the IPCC had available in 2007. He found that North Atlantic hurricane activity increased significantly, but the increase was counterbalanced by diminished activity in the East Pacific, where hurricane-strength storms are 50 per cent more prevalent. The West Pacific showed no significant change. Overall, the declines balance the increases.

"When you average the number of storms and their strength, it almost exactly balances." This isn't indicative of an increase in atmospheric energy manifesting itself in storms.

<SNIP>

The IPCC's AR4 chapter lead was Kevin Trenberth, who features prominently in the Climategate emails. In 2005, the National Hurricane Center's chief scientist Chris Landsea resigned his post in protest at the treatment of the subject by Trenberth.

"I personally cannot in good faith continue to contribute to a process that I view as both being motivated by pre-conceived agendas and being scientifically unsound. As the IPCC leadership has seen no wrong in Dr. Trenberth’s actions and have retained him as a Lead Author for the AR4, I have decided to no longer participate in the IPCC AR4."

Critics point out that an increase in low-intensity storms being recorded is due to better instrumentation. Most are at sea, and thanks to radar and satellites, more are now observed.

[Don Caballero]

1. More anti climate change garbage

Climate change is not going to go away. Man is responsible as proven by science time and time again.

[FarCenter]

2. This doesn't say that climate change is not happening --

Just that increased hurricanes are not demonstrated to be a result.

[Don Caballero]

3. To say the massive increase in hurricanes and the tenacity of the storms

is not related to man made climate change is a lie. Climate scientists are being threatened by Reich Wing nutjobs right now. These kinds of reports are only encouraging them.

[FarCenter]

5. What massive increase in hurricanes? That is what is at issue.

[Statistical]

6. Did you read the OP. The storms are neither increasing in frequency or intensity.

That is the point.

The IPCC is really hurting themselves by publishing stuff so easily refuted.

It does more harm than good to publish stuff based on "science" then it turns out the science is not valid.

Makes global warming look like "faith" rather than science.

[Sancho]

4. Hatten's paper is pretty weak methodology...

He uses very limited post hoc analysis and a simple two-tailed analysis and violates all sorts of assumptions of parametric tests. Compared to the sophisticated climate models at most universities and weather centers now, Hatten is not credible. I'm not a weather expert, but I'm a researcher and I have talked with the folks in marine science and seen their reports here in Florida. The statistical reports are similar for most research even if the exact measures are unique to atmospheric study.

Clear data shows that the ocean water level is rising, the water temperatures are rising, the CO2 is likely the reason, and the climate is in at least a short term change. There are new understandings of earth orbits, ice ages, methane, and similar issues, but man is contributing to the warming and more active weather patterns in the middle latitudes, even if the normal long-term cycles are present. Almost all the credible science points to that conclusion. I have no idea what people can do about it, or if economies will be ruined or whatever; but the climate change seemed pretty well documented.

One minor report on a decade of hurricanes is somewhat irrelevant in the total variability of weather and climate.

[Rage for Order]

8. If you think the methodolgy is weak then prove him wrong

All of the information you need to do so is at the following link:

http://www.leshatton.org/Hurricanes_2010.html

I'll be looking forward to reading your scientific rebuttal that shows Mr. Hatton where he went so terribly wrong in his analysis.

[Viking12]

12. How does an analysis of 1999-2009 data refute the 2007 IPCC claim?

How does an analysis of 1999-2007 data refute the IPCC claim that There is observational evidence for an increase in intense tropical cyclone activity in the North Atlantic since about 1970, correlated with increases of tropical sea surface temperatures.?

[Rage for Order]

13. Read the author's work

The answers are http://www.leshatton.org/Documents/Hurricanes-are-not-getting-stronger.pdf">here

[Viking12]

14. Do you know the difference between the period 1975-2004 and the period 1999-2009?

[Sancho]

15. Hatten makes all kinds of errors...

Hypothesis testing with the z distribution is first course stuff, and Hatten doesn't even attempt to meet the assumptions of parametric hypothesis testing (normality, etc.) If anything, to test one frequency count of a time period vs another is non-parametric even with such an arbitrary unit like the number of hurricanes per year (why not per decade or per minute?) or an ordinal variable like the "intensity scale" (there's no unit of intensity like a pound or inch) is really bad as statistical analysis.
He is wrong in the choice of hypothesis test and uses poor methods. There's also no reason to do experimental hypothesis testing with the old RA Fisher alpha levels applied to something like climate models.

Modern models are "run backwards" and then checked against data for thousands of years (like ice cores). Modern models vary in short term (where is the hurricane going) or long term (how many hurricanes will we have next decade?) predictions and vary widely in complexity.
Hatten is horse and buggy compared to multivariate prediction climate models. Sorry, but Hatton's paper is not good statistical testing. Meanwhile, you can get a taste of things at these links:

http://www.nhc.noaa.gov/modelsummary.shtml

http://www.wunderground.com/hurricane/models.asp

http://www.nhc.noaa.gov/aboutmodels.shtml

http://www.nhc.noaa.gov/aboutsshs.shtml

http://climateprediction.net/

[Statistical]

7. The IPCC are shooting themselves in the foot.

The question isn't if Global Warming exists the question is how accurate are IPCC reports.
They are doing more harm than good with sloppy calculations and observations.
It just gives ammunition to the deniers.

Global warming studies should be based on publicly available data, all original data provided, be completely transparent and easily verifiable.

The IPCC s reducing support for global warming. The deniers don't need to prove it isn't happening they simply need there to be confusion and the IPCC is contributing to that confusion.

[hayu_lol]

9. This is the beauty of science over the ugliness of religion...

science can be tested over and over again until a consensus is reached...and agreement overall. At least until the next batch of numbers/results are published.

Someone tell me the last time anyone tested any part of the bible or even sought out consensus.

[Statistical]

10. That is the beauty. However it is a double edge sword.

If an organization routinely publishes flawed findings or findings based on suspect data than the organization loses credibility.

Science is on the side of global warming but that science can also hurt it if organizations publish sloppy work.

The IPCC needs some kind of top to bottom internal review and start publishing some "bullet proof" findings.

Weak, easily refuted report is better than no report at all. The Denialists sense blood in the water and will be looking for something to sink their teeth into. The best defense is to not give them any targets.

[Viking12]

11. The IPCC is not contributing to that confusion...

Obfuscating bullshit artists like the one referenced in the OP along with the denier friendly media like the Registerare. Read the IPCC section on tropical storms, then read this asshat's analysis. The 2 papers are covering 2 completely different time periods. Of course the results are going to 'differ' -- classic strawman.