LETTER TO THE EDITOR — Efforts to reduce emissions deemed necessary

While your science lesson on the history of the Earth’s climate is an interesting one (see editorial “Exercise in folly,” T.N.M., March 22/99), it completely misses the key arguments raised by the international science community about the risks of human interference with the climate system.

At midnight on your 12-hour clock, humans have managed to alter the natural processes that have governed climate change over the eons. This interference, if unchallenged, appears about to alter both the rate and magnitude of climate change beyond anything that humans have experienced since civilization began. Realistically, this change could bring about temperatures that exceed the highest experienced during at least the last 200,000 years.

During the glacial-interglacial changes experienced by the Earth over longer time scales, the past 10,000 years (the time period over which human civilization emerged) have actually been a remarkably stable and benign period of climate that was in many ways ideal for human development. Climate variations such as the Medieval Warm Period a thousand years ago and the Little Ice Age several centuries ago have indeed occurred every few thousand years. However, these changes have remained within a narrow range of about 1 degree centigrade. Recent studies by experts now indicate that this stable interglacial period, assuming only natural causes for change, is likely to continue for another 10,000 years.

During the past year, several research studies have indicated that current temperatures are already warmer than at any time in the past 1,000 years (including the Medieval Warm Period), and are increasingly difficult to attribute to natural causes alone. While warmer temperatures may sound great in the middle of winter in Canada, climate change is about much more than warmer temperatures. The last El Nino event, modest by comparison, demonstrates how a small variation in climate can have major impacts on weather, people and ecosystems around the world.

Efforts to reduce emissions will limit human interference with the climate system. Furthermore, if planned carefully, such efforts will not devastate our standards of living. Population and wealth are only two factors in determining our emissions. The other two, currently the focus of international negotiations, are energy efficiency (doing more with less) and energy type. While the first of these will provide the most immediate benefits to all involved, the latter is more important in the long term. For example, when we replace combustion of fossil fuels with renewable energies such as wind, solar, hydro-electric or biofuels, the emissions go to near zero, regardless of population or wealth. Studies confirm that we can meet our Kyoto commitment and move beyond this target without compromising our quality of life, or that of poor nations of the world.

The Kyoto agreement by itself will have modest effects on future climate trends. However, studies confirm that concerted efforts to reduce emissions beyond that of Kyoto (including the participation of developing countries) can have a marked effect on the dangerous effects of risks of climate change in subsequent decades.

The National Roundtable on the Environment and the Economy, after consulting extensively with experts from industry, government and environmental groups, did conclude that emissions trading will be one important approach, among many, that will have to be put into place if emissions of greenhouse gases are to be reduced.

Other countries around the world are already moving to put in place domestic trading systems, and international trading is a cornerstone of the Kyoto Protocol. Canada cannot afford to sit on the sideline, ignoring these developments. On the contrary, it is one approach among many that are currently under intensive study.

Hence, the discussions about methods of reducing the risks of climate change are neither hot air nor a “tax grab cloaked in uncertain science.” It is simply a prudent response to a complex but serious problem.

Dr. Gordon McBean

Assistant Deputy Minister,

Atmospheric Environment Service

Environment Canada, Ottawa.