Dear Editor:
A recent letter to the editor offered up another round of climate denial, this time suggesting that we are in danger of losing plant life on earth due to dangerously low carbon dioxide levels. Record-breaking floods in Louisiana have demonstrated the real danger is too much carbon dioxide. So let's get the relevant facts right!
I found four potential sources for the myth of too little CO2 and none are scientists. They include a speaker, a former oil company CEO, an accountant and a businessman. The red herring with this discussion is that CO2 levels have varied from 7000 to 180 parts per million parts per million (ppm). That may have been true in the very distant past, but the fact is that CO2 levels have increased from 280 ppm before the industrial revolution to just over 400 ppm now. At no time during the last 800,000 years, until just recently, have they been above 400 ppm. If low CO2 levels were a problem, how could plants have survived for the last 800,000 years?
Since John Tyndall in 1850, actual scientists have known CO2 in our atmosphere retains heat, which increases land and water temperatures, causing global warming. In fact, 97 percent of scientists and 195 countries around the world agree CO2 emissions are the primary cause of climate change. Temperature and rainfall extremes resulting from global warming are the real problems. Serious scientists warn that we need to limit CO2 emissions or drought and floods will get much worse. Two feet of rain in Louisiana is a dramatic example.
The letter also said a new study stated CFCs, not CO2, have caused temperature increases. The most recent study I found was a May 2013 paper by Waterloo University's Qing-Bin Lu, published in International Journal of Modern Physics B. In February 2014 the same journal published a rebuttal by Dana Nuccitelli and other international scientists demonstrating Lu's research was flawed and finding CO2 was actually the main cause. Even if CFCs caused those temperature increases, regulations limited CFCs, so CO2 from fossil fuels is the issue now.
The fact is that too much CO2 causes rainfall and temperature extremes, and we need to act now to reduce CO2 emissions to avoid increasingly extreme and frequent floods and droughts.