"CO2 is not a pollutant as Gore infers. It is, in fact essential to life on the planet. Without it there are no plants, therefore no oxygen and no life. At 385 ppm current [2008] levels the plants are undernourished. The geologic evidence shows an average level of 1000 ppm over 600 million years. Research shows plants function most efficiently at 1000-2000 ppm. Commercial greenhouses use the information and are pumping CO2 to these levels and achieve four times the yield with [r]educed water use. At 200 ppm, the plants suffer seriously and at 150 ppm, they begin to die. So if Gore achieves his goal of reducing CO2 he will destroy the planet." – Tim F. Ball, Ph.D. Climatology. 2008.