Doctors recognize that apparently harmless events can have catastrophic consequences. This recognition has led them to advocate measures to improve public health, such as the ban against cigarette smoking. Canadian Physicians for the Environment recently persuaded the Ontario government to ban many dangerous pesticides. On the issue of climate change, however, Canadian physicians have been quiet.
In the United Kingdom and Europe doctors have made this issue a public concern. A recent report published in The Lancet (a British Medical Journal) identifies climate change as the most important health issue in the 21st century. Direct effects of climate change include an increase in the range and seriousness of vector-borne diseases. Yet the indirect effects of climate change – on water, habitat and food security- are likely to be the most devastating.
The earth’s temperature has increased 0.8 degrees since the mid-20th Century. This increase has contributed to more frequent natural disasters such as floods, droughts, heat waves and wild fires. Many of these events have caused heavy loss of life.
Climate change has had a large impact on rainfall patterns. Many areas experience droughts that reduce water levels in rivers. Higher temperatures assist contamination of the reduced water flow. Inevitably, there will be an increase in waterborne diseases. Other areas suffer sudden torrential floods that lead to displacement of persons and disruption of food supplies.
One sixth of the world’s population lives in glacial-fed regions. As the glaciers continue to melt there will be a short-term and potentially catastrophic increase in flooding, followed by the elimination of dry weather water flow.
Temperature increase will also affect food production. For every 1 degree increase in temperature, there is an estimated seventeen percent decrease in soy and corn yields. The net effect of these changes is to put extreme pressure on populations, resulting in mass migrations of peoples and civil strike. For example, the civil war in Darfur is in part a consequence of the spreading of the Sahel dessert.
Where are the doctors who recognize the need to stop climate change? The issue is now of such importance that it needs advocacy by the profession. Doctors interested in preserving health must add their voices to this struggle.
Georgina Wilcock, M.D.
(Supporting References provided on request)