Weather Events.

Refer to court ruling 3

Gore says that as oceans get warmer, storms get stronger.

Summer storms draw their energy from the sea, and require warm sea surface temperatures, above a minimum of about 28 ºC to form. High sea surface temperatures however are a necessary but not sufficient condition in order for a storm to develop into a major hurricane. Other necessary conditions are high humidity and low wind shear. Dry air dissipates the hurricane’s nucleus and vertical shear (or the change of winds with height) interacts dynamically in the upper atmosphere to break up the hurricanes core. Whether, or to what extent, global warming is actually increasing the strength and/or frequency of hurricanes is a difficult question for scientists to answer.

See Patrick Michaels on, “Donald Kennedy: Setting Science Back,” World Climate Report, January 20, 2006

See Robert Hart, "Hurricanes: A Primer on Formation, Structure, Intensity Change and Frequency", George C. Marshall Institute, 2006, p. 2.

Wintertime storms on the other hand draw their energy from the collision between cold and warm air fronts. If, as climate models predict, the higher northern latitudes warm more than the lower tropical latitudes, the temperature differential between colliding air masses should decrease, potentially reducing the intensity of some winter storms.

See Richard Lindzen, “Climate of Fear: Global warming alarmists intimidate dissenting scientists into silence”, Wall Street Journal, April 12, 2006.

Have the intensity and frequency of hurricanes increased over the last 30 years as global warming has progressed? The graph below suggests that there was indeed an increase in storm activity since about 1995 in the Atlantic region but the East North Pacific region shows a decrease in storm activity. So it is premature and simplistic to conclude that as oceans get warmer storms get stronger - the process is more complex than that.

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Loading East North Pacific Hurricane Charts ...

Gore says that 2004 was a record year for tornadoes in the U.S

In fact the U.S. National Climatic Data Centre show that the frequency of tornadoes has not increased and that it is only the detection of smaller ones that has increased. As for the bigger tornadoes that have always been detectable, data shows a slight downward trend since 1950.

See 2005 Annual Climate Review Summary. Severe Storms

Gore says that, “over the last three decades, insurance companies have seen a 15-fold increase in the amount of money paid to victims of extreme weather. Hurricanes, floods, drought, tornados, wildfires and other natural disasters have caused these losses.”

Well this is a bit disingenuous. What Gore does not say is whether these losses have been adjusted for increases in population density, wealth, inflation, housing prices and so on. Without these adjustments it is impossible and indeed not even rational to infer climate trends from weather-related financial losses.

This is illustrated by Kunkel et al. (1999) they examined whether increases in mortality and economic losses due to extreme weather events mirrored changes in the physical magnitude of such events. They concluded, “… increasing losses are primarily due to increasing vulnerability arising from a variety of societal changes, including a growing population in higher risk coastal areas and large cities, more property subject to damage, and lifestyle and demographic changes subjecting lives and property to greater exposure.”

See Kunkel, K.E., R.A. Pielke, Jr., and S.A. Shangnon. 1999. Temporal fluctuations in weather and climate extremes that cause economic and human health impacts: a review, Bulletin of the American Meteorological Society, 80: 1077-1098.

Gore says, “In many areas of the world, global warming also increases the percentage of annual precipitation that falls as rain instead of snow, which has led to more flooding in spring and early summer. In 2005 Europe had a year of unusual catastrophes similar to the one in the United States.”

This is disingenuous to say the least because there was, for example, also a record 668 inches of snowfall on Mammoth Mountain in California during 2005-06—the most in 38 years. Many other ski resorts in California, the Pacific Northwest, Canadian Rockies and Vancouver, U.S. Northern Rockies, Utah, and Colorado posted above-average snowfalls in 2005-2006, and many had “high” snowfalls in 2004-05, including three “record high” snowfalls. Again, was this in spite of global warming, or because of it?

See http://www.mammothmountain.com/site_common/lib/pastyears.cfm

See 2005-06 Ski Season Analysis as of July 8, 2006 http://members.aol.com/crockeraf/seas06.htm

Gore says, “Global warming also sucks more moisture out of the soil. Partly as a consequence, desertification has been increasing in the world decade by decade.”

Oh really? Then why do pan evaporation studies, as Roderick and Farquhar (2004), indicate that evaporation from soils has been decreasing since the 1950s in the former Soviet Union, Eurasia, Australia, and North America? Roderick and Farquhar say “it is now clear that many places in the Northern Hemisphere, and in Australia, have become less arid,” and that “in these places, the terrestrial surface is both warmer and effectively wetter.”

See Roderick, M.L. and G.D. Farquhar. 2004. Changes in Australian pan evaporation from 1970 to 2002. International Journal of Climatology 24 : 1077-1090, reviewed by the Center for the Study of Carbon Dioxide and Global Change, “Earth’s Terrestrial Environment is Becoming More Like a Gardener’s Greenhouse,” 14, June 2006,

There has been no U.S. drought in recent decades that was as severe as the drought of the 1930s nor was this drought outside the range of natural variability. Consider this excerpt from NOAA’s Paleoclimatology Program:

“Longer records show strong evidence for a drought; in the 16th century—the depths of the Little Ice Age; that appears to have been more severe in some areas of central North America than anything we have experienced in the 20th century, including the 1930s drought. Tree-ring records from around North America document episodes of severe drought during the last half of the 16th century. Drought is reconstructed as far east as Jamestown, Virginia, where tree rings reflect several extended periods of drought that coincided with the disappearance of the Roanoke Colonists, and difficult times for the Jamestown colony. These droughts were extremely severe and lasted for three to six years, a long time for such severe drought conditions to persist in this region of North America. Coincident droughts, or the same droughts, are apparent in tree-ring records from Mexico to British Columbia, and from California to the East Coast.”

See North American Drought: A Paleo Perspective.

The Centre for the Study of Carbon Dioxide and Global Change summarizes the literature on floods and climate variability:

Asia: “The results of these (five) studies from Asia provide no support for the climate-alarmist claim that global warming leads to more frequent and severe flooding. If anything, they hint at an opposite effect.”

See http://www.co2science.org/scripts/CO2ScienceB2C/subject/f/summaries/floodsasia.jsp

Europe: “In light of this body of evidence [17 studies], it is clear that for most of Europe, as well as many other parts of the world, there are simply no compelling real-world data to support the climate-alarmist claim that global warming leads to more frequent and severe flooding.”

See http://www.co2science.org/scripts/CO2ScienceB2C/subject/f/summaries/floodseuro.jsp

North America: “Taken together, the research described in this Summary [21 studies] suggests that, if anything, North American flooding tends to become both less frequent and less severe when the planet warms, although there have been some exceptions to this general rule.”

See http://www.co2science.org/scripts/CO2ScienceB2C/subject/f/summaries/floodsnortham.jsp