I maintain that current levels of tropical storminess are unprecedented in the historical record and that a global-warming signal is now emerging in records of hurricane activity.

* the all-event PDI chart that Emanuel e-mailed to Willis is noticeably different from 1995 on, when compared to his original Figure 1. Any idea if that is due to Emanuel changing his smoothing technique, or due to a change in his database?

Probable a change in the smoothing, as he had been notified by Landsea of the problem.

w.

-reluctance to get involved
-ego’s drive to show someone up
-fanatic hate of error & lies
-love of camaraderie

Dynamic forces jostling with & against each other (tension, compression) leading to cyclic patterns of progress. Sometimes lecturing trolls. Sometimes doing real work. It’s all good.

In a former life I was part of a group that on occasion would take apart technical papers looking for findings that could be applied to an electronics manufacturing process. Others in the group were often much more technically orientated and knowledgeable than I and that made the process a more enjoyable learning experience for me.

An aspect that seemed constant with this process was that the science and technical parts were much more readily understood than the motivations of the authors of the papers. We often would contact authors and put questions to them directly when they were not employed by a competing organization or meet them at conferences and discover that we had the science right but the personal motivations and, therefore, sometimes the stated conclusions or limitations, wrong. I always thought a few beers and an engineer’s/scientist’s ego were a deadly combination for extracting background information.

Because the start and end points are low and high respectively for both the PDI and the SST, this converts a “U” shaped curve into more of a hockeystick shape, by pinning the start low and the end high

Very sharp observation. I was just going to investigate that possibility. This is exactly where my U-shaped smoothing was deviating from his HS.

* the all-event PDI chart that Emanuel e-mailed to Willis is noticeably different from 1995 on, when compared to his original Figure 1. Any idea if that is due to Emanuel changing his smoothing technique, or due to a change in his database?

* the inclusion of 6N to 9N in the SST box helps convert an oscillating SST pattern (1930-2003)into more of a hockey stick.

1) While there is a significant trend in the HadISST in the area from 1949-2003, there is no significant trend 1931-2003.

2) While there is a small relationship between the September HadISST sea temperature and the original PDI (r^2 = 0.21, p = 0.01), the relationship drops to r^2 = 0.08, p=0.12 when we use the August to October HadISST sea temperature … looks like my original suspicions of cherry picking were correct.

More to come … tomorrow.

w.

Emanuel used the HadISST data, smoothed three times (not four, as with the PDI data). Here’s the match:

At this point, we can do some actual analysis of the results … the three unsmoothed datasets, appended at the end of this post, have the following characteristics.

1) NONE of the three has a significant trend. The figures are as follows:

ITEM , Orig PDI , HadISST , Adj PDI
Trend z , -0.87 , 1.37 , -0.10
Kendall z , -1.26 , 1.58 , -0.62

The “Trend z” is the significance of the trend, using Nychka’s adjustment for autocorrelation:

The “Kendall z” is the significance of the trend, using Kendall’s non-parametric trend test.

2) The SST is related to both the adjusted and unadjusted PDI, as follows:

ITEM , Orig PDI vs HadISST , Adj PDI vs HadISST
r^2 , 0.21 , 0.25
p value , 0.01 , 0.002

The p value has been calculated using Bartletts formula for the effective N,

While these relationships are statistically significant, they are quite small.

3) The method of smoothing (pinning the end points and repeatedly using a 1-2-1 smoothing filter) distorts the results. By pinning the endpoints, the start and finish of the curve are held in place, and the smoothed curve is adjusted to meet them. Because the start and end points are low and high respectively for both the PDI and the SST, this converts a “U” shaped curve into more of a hockeystick shape, by pinning the start low and the end high …

It’s 1:15 AM … I’m going to bed.

w.

THE DATA

Year , Orig PDI , HadISST , Adj PDI
1949 , 10.82 , 27.81 , 9.25
1950 , 30.64 , 27.92 , 26.2
1951 , 16.66 , 28.11 , 14.25
1952 , 10.41 , 28.37 , 8.9
1953 , 11.46 , 28.08 , 9.8
1954 , 13.45 , 27.81 , 11.5
1955 , 24.73 , 28.06 , 21.35
1956 , 7.08 , 27.69 , 5.3
1957 , 10.26 , 28.16 , 8.7
1958 , 14.62 , 28.20 , 12.5
1959 , 8.77 , 27.68 , 7.5
1960 , 12.96 , 27.86 , 10.2
1961 , 26.78 , 27.88 , 22.9
1962 , 3.74 , 27.97 , 3.2
1963 , 14.11 , 27.94 , 11.95
1964 , 20.77 , 27.58 , 18.05
1965 , 10.06 , 27.80 , 8.6
1966 , 17.42 , 28.05 , 14.9
1967 , 14.09 , 27.78 , 12.05
1968 , 3.18 , 27.74 , 3.65
1969 , 18.30 , 28.25 , 15.65
1970 , 3.75 , 27.88 , 3.75
1971 , 9.25 , 27.61 , 9.25
1972 , 2.9 , 27.52 , 2.9
1973 , 4.15 , 27.79 , 4.15
1974 , 7.5 , 27.46 , 7.5
1975 , 7.8 , 27.63 , 7.8
1976 , 8.6 , 27.94 , 8.6
1977 , 2.95 , 27.72 , 2.95
1978 , 6.6 , 27.59 , 6.6
1979 , 11.85 , 28.09 , 11.85
1980 , 19.3 , 28.20 , 19.3
1981 , 9.95 , 27.96 , 9.95
1982 , 3.35 , 27.67 , 3.35
1983 , 1.5 , 27.73 , 1.5
1984 , 7.45 , 27.68 , 7.45
1985 , 9.3 , 27.76 , 9.3
1986 , 3.5 , 27.94 , 3.5
1987 , 2.65 , 28.23 , 2.65
1988 , 13.1 , 28.03 , 13.1
1989 , 16.45 , 27.95 , 16.45
1990 , 8.5 , 28.34 , 8.5
1991 , 3.45 , 27.60 , 3.45
1992 , 8.85 , 27.78 , 8.85
1993 , 3.5 , 27.82 , 3.5
1994 , 2.65 , 27.79 , 2.65
1995 , 24.8 , 28.32 , 24.8
1996 , 19.55 , 28.12 , 19.55
1997 , 4.15 , 28.16 , 4.15
1998 , 21.75 , 28.48 , 21.75
1999 , 21.85 , 28.36 , 21.85
2000 , 12.2 , 27.99 , 12.2
2001 , 11.25 , 28.38 , 11.25
2002 , 6.35 , 28.01 , 6.35
2003 , 22.6 , 28.62 , 22.6