Recent letters to the editor reflect an increasing concern about climate change. That’s good. Nevertheless, many misconceptions persist, among which are the following:
1. The contribution of human activity is too small to matter. Response: There are massive natural sources of greenhouse gasses and equally massive natural mechanisms for absorbing the gasses. It takes only a relatively small amount of additional carbon dioxide to upset the balance.
2. The current rise in global temperature is just part of a longstanding cyclic pattern. Response: Indeed, temperatures and carbon dioxide levels have waxed and waned (together) over the geological timescale, due primarily to orbital shifts and continental movement. During the past 12,000 years, there have been warm and cold periods but no overall trend. This changed dramatically after 1850, when temperatures and carbon dioxide levels began to rise at an unprecedented rate.
3. We cannot trust climate scientists. Response: What would motivate thousands of scientists around the world to fabricate data and invent a scenario so injurious and potentially catastrophic to everyone? The facts are accessible in peer-reviewed scientific articles and in books written by knowledgeable science writers. There is no good excuse for remaining ignorant of this literature.