To the editor:

I read with sadness an Oct. 26 Letter to the Editor concerning the science behind global warming. The letter writer is a nonbeliever of the majority of scientific fact that proves human activities do increase the amount of heat-trapping greenhouse gases (like carbon dioxide) in the atmosphere.

Global warming refers to the observed increase in the Earth’s “averaged” air temperature measured near the surface. The data to support this observation is collected from thousands of weather stations located around the world. Data collected since 1880 clearly shows the Earth has warmed and the greatest amount of warming has occurred over the past 40 years. Not surprisingly, the largest amount of warming is in our oceans (which cover 80% of the Earth).

The mechanism of global warming is similar to a garden greenhouse used to extend the growing season. The greenhouse panels allow the sun’s heat energy to enter, but then prevent some of the reflected energy from traveling outdoors. Thus the greenhouse stays warmer than the outside. The same occurs when humans emit greenhouse gases that behave similar to the greenhouse panels.

Humans have released 500 billion metric tons of carbon dioxide into the atmosphere in the past 200 years (primarily from burning fossil fuels). During that time measured levels of carbon dioxide increased 40%. And during that period scientists measured increases in sea surface and air temperatures, increased global sea levels and a rapid decline in summertime Artic Sea ice.

Scientists are not motivated by research dollars, they use the tools of observations and experiment to seek the truth. The letter to the editor quotes a Dr. Spencer as a sole authority on the topic. If I invited 100 respected climate scientists in a room, the other 99 would mostly disagree with Spencer’s conclusions. He supports mostly controversial opinions and receives his support from the Heartland Institute, an organization that not only denies the established science of global warming but also supports tax credits for big business and deregulating the safety of our air, water, and food.

It is not a bad thing to realize humans impact the environment. What should concern us all is if that impact leads to less economic and social opportunity for our children and grandchildren. A good place to educate yourself about the science of global warming and climate change is available by Googling “NOAA Frequently Asked Questions on Global Warming.”