Myths - 'Extreme Weather Events are Expected to be More Common if the World Warms. This Has Already Started - Drought, Floods, Forest Fires, etc. are on the Rise as a Result of Our Greenhouse Gas Emissions.'
MYTH #5 - 'Extreme Weather Events are Expected to be More Common if the World Warms. This Has Already Started - Drought, Floods, Forest Fires, etc. are on the Rise as a Result of Our Greenhouse Gas Emissions.'
THE ENVIROTRUTH: Dr. Madhav Khandekar, a meteorologist with 25 years experience at Environment Canada, showed in a study about to be published that extreme weather events (heat waves, floods, winter blizzards, thunderstorms, hail, tornadoes) are not currently increasing anywhere in Canada. "Extreme weather events are definitely on the decline over the last 40 years," concludes Dr. Khandekar.
He shows that the hottest summers of the 20th century in Canada were during the dust bowl years of the 1920s and the 1930s, not the 1990s. Dr. Khandekar summarizes, "The observed climate change of the last 50 years is beneficial to most regions of Canada in terms of lower heating costs and an enjoyable climate."
According to Dr. John Christy, Professor and Director, Earth System Science Center at the University of Alabama, the frequency of hurricanes, thunderstorms, hail and tornadoes have not increased in recent years either. Weather just seems unusual and dangerous these days because of media focus. If the planet warms, the temperature differential between the Earth's poles and equatorial regions will drop, resulting in weather that is even more tranquil. The geologic record clearly shows that today's climate is in no way extraordinary or identifiably different from what one would expect due to entirely natural processes.
Source: Oregon Institute of Science and Medicine
The same is true of droughts. Dr. Christy explains, "When looking back over the past 2,000 years we see that the most significant droughts in the Southwestern U.S., for example, occurred prior to 1600." Dr Tim Patterson, professor of earth sciences (Paleoclimatology) at Carleton University, maintains that the present drought on the Canadian prairies is part of a natural cycle that has gone on for thousands of years. "There are many droughts that are documented to have been much worse than the present one, and long before the initiation of human produced greenhouse gases," Dr. Patterson explains. "The worst drought (in Canada) in the last 1,000 years lasted from 1680-1720 during an episode of cold from which we only began to recover in the 1890s." Not surprisingly, in previous centuries, North America's great plains were referred to as the 'Great American Desert,' an area that should not be extensively farmed, specialists recommended.
But what about the frightening predictions of computer models we keep hearing about? Dr. Tom Wigley of the U.S. National Center for Atmospheric Science explains, "There is no consensus between (computer) models on changes in... temperature and precipitation. Even the best models perform poorly in simulating such variability."
Sir John Houghton, chief scientist of the United Nations-sponsored Intergovernmental Panel on Climate Change (IPCC), agrees and adds, "...there is little agreement between models on... changes in storminess...Conclusions regarding extreme events are obviously even more uncertain."
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