Moderation in Pursuit
How many network
"news" programs presented this fall's perfectly average hurricane season as
a sign of dreaded global warming? How many times has President Clinton remarked that the
"increase" in extreme weather events seems pretty obvious, after he was seen
toting Ross Gelbspan's dopey reverie The Heat
is On? We can't even count them alland we don't even want
toknowing as we do that these and a lot of other statements about wacky weather are
just plain wrong.
That is, if we are to
believe the recent compendium Weather and Climate
Extremes, edited by Thomas Karl, head of the National Climatic Data Center, and two
others. This tour-de-force volume, hot off the presses, should be required reading for any
climate cassandra, including Clinton or his sidekick.
A comprehensive paper
by aptly named hurricanologist Chris Landsea puts it pretty bluntly. Landsea, who played
on the 1984 Olympic water polo team, isn't shy about throwing cold water on the folks
from "Working Group III" of the United Nations Intergovernmental Panel on
Climate Change (IPCC).
Figure 1. No trend exists in the number of Atlantic
hurricanes per year since 1944, the year good records began.
III's Economic and Social Dimensions of Climate
Change, whose chief author is IPCC head Robert T. Watson, stated that we could save
8,000 lives per year and $630 million in hurricane damages if only we reduced our
greenhouse gas emissions. As Landsea puts it: "There is an obvious inconsistency
between the projections by IPCC Working Group III....and the conclusions of Working Group
I [the science guys], which stated that 'the state of the science does not allow
assessment of future changes.'" Landsea goes on to say:
...the logic of the
IPCC Working Group III is fundamentally flawed...the climatological record gives no
indication that society can modulate hurricane impacts through energy policies. That is,
as atmospheric CO2 levels have
increased, "there is currently no evidence that there has been systematic change in
the observed tropical cyclones in the observed tropical cyclones around the globe"
(Landsea, 1998)...There is no evidence to suggest that society can intentionally modulate
tropical cyclone frequencies and magnitudes through energy policies. Therefore, policy
responses to hurricanes ought to focus on the reduction of society's vulnerabilities
to hurricanes, rather than on the prevention of storms themselves (Pielke and Pielke,
The next paper, by
British researcher Phil Jones, reiterates what WCR
readers have known for yearsthat the longest high-quality temperature record in the
world, the 225-year daily (!) Central England Temperature, "shows no significant
increase in very warm days in recent years, but there is a marked decrease in the
frequency of very cold days." How too, too bad. Using more recent global records,
Jones demonstrates that the area of the planet exceeding its 90th percentile in
temperature has increased threefold, while there has been an equal and opposite drop in
the area of very cold temperaturesthose below the 10th percentile. Jones neglects to
remind us of the well-known fact that this is primarily because of a warming in the
coldest winter temperatures in Siberia and northwestern North America, according to the
Figure 2. There is no evidence for increasing wind speeds in
Atlantic hurricanes since 1944.
Following this entry
is a compilation of climate extremes in Northern and Central Europe, by R. Heino and 10
Below, we quote some
notable results listed in their "Concluding Remarks":
a decrease in
the diurnal [daily] temperature range
a decrease in
the number of frost days
no major change
in daily precipitation extremes
no major change
in the number of precipitation days [greater than] 10 mm
intensification of strong winds
a decrease in
the occurrences of thunderstorms and hails.
In the next paper,
Neil Plummer, from the Australian Bureau of Meteorology, shows the problems with
"outlier" data. He reports an increase in the percentage of Australia
experiencing precipitation in the 90th percentile or above; but, as the accompanying
figure shows, an awful lot of this "trend" occurred because of one very wet year
around 1975. There is also a decrease in the frequency of Australian rain below the 10th
percentile. Not a bad outcome from global warming for the driest continent in
Figure 3. Percentage of Australia experiencing extreme wet
conditions on an annual basis.
WCR readers may recall
our recent article pointing out that an AP story relating increased flooding in China to
global warming had no basis in fact. The truth is, there's no change in the amount of
land area there receiving heavy rain, as Panmao Zhai shows, even though there is an
increase in flood frequency. Can anyone here say "deforestation"?
As for temperature
The mean minimum
temperature has increased significantly in China in the past 40 years, especially in the
winter in northern China. Meanwhile, nationwide cold wave activity has weakened and the
frequency of cold days in northern China has been reduced significantly. Mean maximum
temperatures display no statistically significant trend for China as a whole. However,
decreasing summer mean maximum temperatures are obvious in eastern China, where the number
of hot days has been reduced.
Will someone please
send copies of Weather and Climate Extremes to
President Clinton, Al Gore, and Ross Gelbspan? C'mon, Tom Karl, go to the mail
roomwe know you're reading this!
T.R., et al., Eds., Weather and Climate
Extremes: Changes, Variations and a Perspective from the Insurance Industry, Boston:
Kluwer Academic Publishers, 1999.