I commend you regarding your recent articles on global warming. I have some comments regarding the letter by Brett Malin in the Wednesday, Jan. 10, Chinook Observer.
Mr. Malin is correct in that the earth over its history has undergone many periods of warming and cooling. Indeed, the carbon dioxide level in the atmosphere has been much higher millions of years ago than the values we measure today. However, the surface of the earth today is a scant replica of what it was millions of years ago.
Carbon dioxide levels in the atmosphere today are over 377 parts per million. That is higher than it has been over the last 400,000 years. ("Climate Change Impacts on the United States," Cambridge University Press.) The rapid increase during the 20th century from less than 300 ppm to today's value (the "hockey stick" effect) has been labeled "not just unusual, but completely out of character for the past 600 years." ("Global Climate Change," Rowman & Littlefield, Publishers.)
Mr. Malin's solution of more carbon dioxide thus more plants to absorb it might be a partial solution if humans were not desecrating forests far faster than they are being replenished. Yes, before humans, I suspect that nature was self-balancing. However, the human factor has thrown that self-balancing theory into disarray.
The debate as to whether our climate is warming is over. The scientific data supporting it is overwhelming and still increasing. What remains is to what extent humans are altering that self-balancing act. Today the majority of scientists believe the human factor is the primary cause of the increase in carbon dioxide and subsequent warming. And as for humans thriving during warmer periods, I guess that depends on where you are located. The Long Beach Peninsula is very close to sea level.
(The writer was meteorologist in charge of the National Weather Service in Portland, retiring after more than 35 years.)