Faulty forecasts: With more and more scientists questioning the real cause of recent global warming, rushing to ratify the Kyoto accord is ridiculous in the extreme.

By Dr. Madhav L. Khandekar National Post (Toronto) November 21, 2002

It is important to correct the perception fostered by Environment Minister David Anderson and his unofficial spokesman, Andrew Weaver from the University of Victoria, that only a few "skeptics" -- scientists "at the margins of the issue" practicing "outlier science," as the Minister said last week -- have problems with the scientific rationale for the Kyoto Accord. In reality, despite Dr. Weaver's contention in the National Post last week, hundreds of climate scientists in Canada and around the world are now beginning to question the validity of projections made with today's insufficiently verified climate models.

Even at Environment Canada, many experts in the fields of operational weather forecasting, cloud physics and climate variability are not confident about the accuracy of the models' projections. However, these experts are afraid to publicly criticize climate models cited by the government because of the dictatorial environment within the department, where senior managers have already accepted the notion that the global warming/human link is a fait accompli.

Dr. Weaver says confidently, "... humanity is the primary cause of late 20th-century climate change." This is unfounded. More and more atmospheric scientists are now questioning the real cause of recent warming. According to Dr. William Gray, professor of atmospheric science at Colorado State University, the warming may be entirely due to natural atmospheric variability and have nothing to do with increase in greenhouse gases at all. Dr. Gray further points out that the inadequate treatment of water vapour distribution in the atmosphere by most climate models can lead to unrealistically high forecasts of warming in the future. Dr. Patrick Michaels, professor of environmental sciences at the University of Virginia, puts the situation into perspective: "Temperatures measured by surface thermometers have risen about 0.7C in the last 100 years, but about half of that warming occurred before most changes in atmospheric carbon dioxide [i.e. since 1940]."

A large area of Eastern Canada and Northwest Atlantic Ocean has cooled in the last 50 years by as much as 1C to 3C in some places. Why? The 2001 report from United Nations' Intergovernmental Panel on Climate Change (IPCC) does not elaborate on this except to suggest a possible role of the entirely natural atmospheric phenomena, the North Atlantic Oscillation, which has been a subject of intense research in recent years. If the cooling in Eastern Canada can be explained by such slowly varying natural atmospheric oscillations, it is possible to explain the warming of the Canadian Prairies by other natural oscillations such as El Niño/Southern Oscillation. Dr. Gray, Dr. John M. Wallace, professor of atmospheric sciences at the University of Washington, and many other atmospheric scientists are now suggesting this kind of mechanism to explain recent warming of the Earth's surface.

As the leader of the climate modelling group at the University of Victoria, Dr. Weaver seems to have an unjustifiably strong faith in the projections of computer climate models and cites a 1.5 - 5C warming over the next 100 years. Yet, the climate model developed by scientists in Victoria cannot even produce accurate forecasts for the next three to six months! Climate modellers often respond that their models are not designed for making such short-range predictions. Surely it would be prudent to redesign their computer simulations to make accurate short-range forecasts before using them to help guide policymaking concerning climate a century from now.

At the U.S. Congressional hearing on the use of climate models in July, 2002, Dr. James O'Brien, director of Florida State University's Center for Ocean-Atmospheric Prediction Studies, commented that the Canadian model appears to be simulating climate for a planet other than Earth! Dr. O'Brien further revealed that the Canadian model does not simulate El Niño or tropical monsoon, both being important climate signals without which future climate projections are meaningless. Dr. Michaels sums up: "The Canadian Climate Center model performs worse than a table of random numbers when applied to 10-year averages of U.S. temperatures." Dr. Michaels contends that the warming over the next 50 years can be estimated to be around 0.75C, at the very bottom of the projections Dr. Weaver cites. Dr. Michaels' conclusion matches well with the predictions of NASA's prestigious climate modeller Dr. James Hansen, as well as that of Dr. Myles Allen, of the University of Oxford Atmospheric, Oceanic and Planetary Physics group, who runs Britain's Hadley Center climate model. All of these results appear in the refereed scientific literature, and all appeared after the United Nations report.

Strangely, Dr. Weaver appears to lean heavily on anecdotal evidence from native people in his beliefs about climate change in the North. This approach in no way addresses the causes of climate change. Professor Fred Michel, an Arctic regions specialist in the Department of Earth Sciences at Carleton University, explains that the problem being experienced by the natives is not due to any unnatural climate change. Instead they are having more difficulty now than in previous generations because they have evolved from a nomadic, hunting society -- one which moved as the climate changed -- into one that is now staying in one place with fixed buildings highly susceptible to structural problems due to the normal freeze/thaw cycle and natural climate variations. Dr. Michel also points out, "... glaciers have retreated but this is not unusual in a global historical perspective." He explains that the changes natives have observed in stream flow are generally the normal result of variations in daily temperatures -- what was a tranquil stream in the morning can transform, on a sunny day, into an impassable torrent raging down the valley by mid-afternoon. By mid-evening the flow begins to subside, and by midnight the stream is again passable. Dr. Michel concludes, "Things are changing, but man may not be the cause."

Next, Dr. Weaver tells us "We have seen warming in the last 100 years that compares to natural variability seen over thousands of years." However, he ignores the fact the IPCC 2001 document confirms that the recent warming is less than that which occurred between 1910 and 1940. What caused that sudden warming? Any human impact was either non-existent or very weak then.

Dr. Weaver also completely neglects to mention a number of very important contributors to gradual warming that will in no way be affected by implementing Kyoto. Take the urban "heat island" effect, for example. The IPCC contends that urbanization may have contributed to no more than 0.06C over the last century. However, recent research suggests that it may be at least 0.1C and perhaps higher. A study about to be published in the Journal of Climate by Dr. Arthur De Gaetano, a Cornell University climatologist, carefully analyzes the urban-rural temperature differences and concludes that the urbanization impact for some locations could be as much as three times higher than previously believed! Dr. De Gaetano's study seriously questions the actual magnitude of the recent warming due to greenhouse gases.

Dr. Weaver is also glaringly vulnerable in his belief that weather will be more extreme in a warmer world. Along with Henry Hengeveld and other Environment Canada spokespeople, pro-Kyoto forces have tried to associate everything from snowstorms to floods to droughts with planetary warming. As Dr. Michaels explains, "In general, a warmer world has a lower equator-to-pole temperature contrast, and it is this contrast that provides energy for the jet stream, which powers almost all surface cyclones. Reducing this contrast reduces their intensity." The global warming/extreme weather link is more perception than reality. A careful analysis of the 20th-century data reveals that extreme weather events such as thunderstorms, tornadoes, droughts, floods, heat waves etc. are not increasing anywhere in Canada. The dust bowl years (1910 - 1940) were in general hotter during summer months than the decade of the 1990s, which many Kyoto supporters claim was the warmest decade on record. The deadliest heat wave in Canada occurred in July, 1936, when the temperature in Toronto hit 41C three days in a row, killing more than 1,000 people in the Prairies and Southern Ontario. The worse flood in Canadian history was due to Hurricane Hazel (October, 1954) and killed more than 75 people in the western suburbs of Toronto. No meteorologist or climatologist has blamed this on global warming. Why do alarmists then blame the recent flooding (Saguenay, July, 1996; Red River, April, 1997) on global warming?

In my report on extreme weather events and trends, soon to be published by Alberta Environment, I reference a recent study by Dr. Xuebin Zhang and other Environment Canada scientists which demonstrates that the average number of "heavy" precipitation events per location south of 70*N have declined in the last 30 years. I also conclude in my report that the likelihood of increasing incidences of extreme weather events in the next 10 to 25 years is very small.

Climate change is the most complex issue humanity has ever handled. To pretend that the science is sufficiently mature to substantiate rushing forward with ratifying Kyoto is ridiculous in the extreme. On hearing about David Anderson's confident predictions of the dire effects of not ratifying Kyoto, Dr. Richard Lindzen, professor of meteorology at the Massachusetts Institute of Technology and one of the lead authors of the IPCC report, laughed: "There is a certain charm when politicians are so certain of the science when the scientists are not."

Dr. Madhav L Khandekar, a former research scientist with Environment Canada, holds a PhD in meteorology and has worked in the fields of climatology, meteorology and oceanography for over 45 years.