A few years ago I wrote a "Letter to the Editor" in response to a letter by a skeptic. That letter inspired a series of essays which this year became a blog. My website is called lessonsonscience.com but a better way to access it is simply to Google Essays on Science for the Common Good.

I encourage you to read all of the first 11 essays plus the preface and outline but a few of them do go into some detail on some of the topics which now are aimed primarily at high school or college biology students.

I would ask any doubter, ”Do you believe that temperatures on a world-wide basis are increasing and if so what are the factors (causes) if not from anthropogenic (human) effects of increased greenhouse gases?” To this I suggest reading essay XIV, especially paragraphs 1 and 4. A basic premise is that photosynthesis removes CO2 from the atmosphere and any process that returns CO2 to the air such as cellular respiration, decay, and burning fossil fuels at a faster rate than what photosynthesis removes is a bad thing since it offsets the normal ecological balance of the two processes. See essays VII and VIII.

I have converted my major points to bold print. I realize that I am asking readers to have newspaper in hand as you sit at your laptop, PC, or other device but time and space is of the essence. Concerning the human imprint on the environment, let us turn to essay XIII.

It is essential that we understand some terms before proceeding further.

• Greenhouse effect: light and heat from the sun enters the atmosphere striking the earth’s surface where some is absorbed by surface features and converted into other forms of energy such as chemical energy of food. Some is radiated back into space, and some is trapped in the atmosphere by clouds and various pollutants thereby raising the temperature similar to a hothouse or greenhouse, thus the term “greenhouse effect”.

• Global warming: the cumulative result of the greenhouse effect on a worldwide basis.

• “The transfer rate of carbon from the atmosphere by photosynthesis just about equals the rate at which respiration and decay return carbon to the atmosphere. However, when fossil fuel burning is added to the equation, the rate of CO2 returned to the atmosphere is greatly favored.”

In 1991 the National Association of Biology Teachers (NABT) adopted the following position.

Causes of climate change

1. Increased use of fossil fuels

2. Increased rate of deforestation, resulting in less carbon “locked up” in the forest

3. Increased amount of “greenhouse gases” (CO2,CH4 (methane), N2O (nitrous oxide), CFCs (chlorofluorocarbons)) causing the atmosphere to absorb radiant heat

4. Growth of the human population as it affects all of the above

Consequences of global warming

1. Shifting of agriculture zones

2. Desertification and local mass extinction

3. Changes in animal migration patterns

4. Sea levels rise as a result of melting polar ice and thermal expansion in the oceans, which can cause destruction of human structures and natural habitats along sea coasts

The Oct. 19, 2008, issue of the Rockford Register Star article “On thin ice” says “the Arctic Ocean is recording record temperatures as the ocean is getting warmer and less salty as ice melts”. Also from essay XIV: The graph below shows ice core data charting average temperature from the past thousand years in the northern Hemisphere. The line at 0.0 represents average temperature from 1961 to 1990. Any year with an average temperature below the 0.0 line was colder than average and is shown in blue; any year with an average temperature above the 0.0 line was warmer than average and is shown in red.” I’ll let readers draw their own conclusions.

Remember, more people on the planet means more greenhouse gases and more tipping of the photosynthesis/carbon dioxide returned balance.

Larry Baumer writes the blog Essays on Science for the Common. He taught high school and community college and was a citizen scientist for the Illinois Department of Natural Resources in its RiverWatch program (monitoring water quality) for 14 years.