H. Leighton Steward

Earth Day this year is marked with dueling reports about what climate change means for the future of our planet. The United Nations Intergovernmental Panel of Climate Change (IPCC) has declared that human activity is the cause of most of the temperature increases of recent decades, and warns that sea levels could conceivably rise by more than three feet by the end of the century if emissions continue at a runaway pace.

On the other side and backed by thousands of peer-reviewed papers, a study released by the Nongovernmental International Panel on Climate Change (NIPCC) contrasts starkly with the recently released UN report that finds probable severe impacts from global warming. The NIPCC report finds that warming from greenhouse gases will be so small as to be indiscernible from natural variability. The impact of modestly rising CO2 levels on plants, animals, and humans has been quite positive while the costs of trying to limit emissions are huge and counterproductive.

So what is the real truth? Mother Nature has been in control of Earth’s climate for all of Earth’s history but the United Nations IPCC now proposes that she has relinquished that job to a weak greenhouse gas named carbon dioxide (CO2). This group hypothesizes that since the Industrial Revolution, about 150 years ago, humans have begun to put enough emissions of this weak gas into the atmosphere to wrest control from Mother Nature’s grasp.

CO2 flunks the empirical test of being a dominant cause of climate change. For the past 16 years, Mother Nature has ceased Earth’s warming even as man-made CO2 levels have risen. While this brief pause is not absolute proof that CO2 is a weak greenhouse gas, it should make us want to examine more of its historical influence on the climate and environment.

The climate has continually changed, even for long periods when CO2 levels stood still; for decades, hundreds and even thousands of years. The Earth-greening impact of man’s additional CO2 is well documented by a NASA satellite that shows that Earth has been greening for three successive decades despite all the bad things we have done to Earth. You can thank the combustion of fossil fuels for fertilizing the greening Earth with additional CO2.

For those of you that profess to being true environmentalists, there is very good news as to what we humans are doing to the planet that is quite beneficial. Here is what the non-political NIPCC has concluded its multi-year study:

• Neither the rate nor magnitude of twentieth century warming lie outside the range of normal variability.

• Sea Level rise is not accelerating, no global increases in rainfall or evaporation or of the number or intensity of extreme weather events are occurring.

H. Leighton Steward

H. Leighton Steward is a geologist, environmentalist and chairman of plantsneedco2.org.