ed - dm
These are unique times
I agree with my neighbor and friend John Alford about much of what he wrote in a March 8 letter (Inconvenient truth), However, his claim that we "should keep in mind that these are not unique times and events, we have been there before" is not what I see in the world today.
While it is true that there are natural cycles at work during all times, it is also true that many current cycles are happening more rapidly than we have seen before. Rapid ice cap loss at the poles, glacier loss at a rate not observed before, and some other like occurrences. What this means is it is unique.
Carbon dioxide levels in the atmosphere were near 280 parts per million in 1880. Today we are at or near 400 ppm and climbing more rapidly each decade. Four hundred ppm is the highest in the last 800,000 years and the rise starts near the time of the European Invasion of North America and the Industrial Revolution (1750-1800).
These are, indeed, unique times. Never before have seven billion people stressed this planet near unknown limits and had such an effect, in a short time, as now.