The article goes on to explain that different species of plants have different optimum levels of CO2 that they can effectively use. Most green plants are in the 1,000 parts per million range, but unicellular algae can use CO2 concentrated in the 10,000 to 50,000 ppm range. There is no debate in the scientific community that the Earth's atmospheric concentration of CO2 has been increasing. According to Dr. Wittwer, if global warming was to occur due to increased levels of CO2, the winners would be the plant kingdom because of better photosynthesis and longer growing seasons. In any algorithmic solution to a problem, you must enter all of the known variables accurately at the beginning to get correct results at the end.
Computer models can only be a best guess as to what the future holds.
However, using these same models with past known levels of CO2, predicts a larger increase in temperature than the actual recorded temperature increase. The article states that these sulfate particles act differently than greenhouse gases because they tend to block sunlight rather than transmit it. These particles cool the earth, somewhat counteracting the warming effect of greenhouse gases. For a powerful example of the cooling caused by airborne pollutants it only takes a look back to 1991 and the eruption of Philippine Mount Pinatubo. Overall global temperatures dropped by 1 degree in that year, supposedly from the eruption s ash and dust cloud.