Sen. Chester Crandell (R-Heber) at a recent senate committee hearing said reducing the carbon dioxide in the atmosphere would inhibit plant growth so that “we’re going to starve to death because we cannot produce enough food for the amount of people being produced on the Earth.”
Testimony on a bill intended to prevent the federal Environmental Protection Agency from limiting the pollutants produced by coal-fired power plants featured an exchange between Crandell, who represents Rim Country, and witnesses testifying against the bill.
Among other things, Crandell insisted that because some scientists disagree about the strength of links between rising carbon dioxide levels, rising average temperatures and human pollutants, “the science must be wrong.”
But Crandell’s most persistent challenge to the scientific consensus on the impact of carbon dioxide on rising temperatures centered on the impact of the pollutant on plant growth.
“If we continue to push down the amount of CO2 in the air, what’s that going to do to crop production we need to feed the people of the world?” he said in support of Senate Concurrent Resolution 1022, which would assert the state’s primary role in regulating air pollution from power plants. The bill would also bar the federal government from requiring pollution-reducing equipment that “is not commercially available or technologically feasible and that do not recognize the state’s primary role in establishing and implementing plans to achieve emissions reductions for existing units.”
The bill comes in the wake of the Environmental Protection Agency’s effort to require a group of utility companies to put smokestack scrubbers on the Navajo Generating Plant or shut down at least a portion of the plant near Page, which provides most of the power to run the pumps of the Central Arizona Project.
Crandell insisted the Legislature should not regulate carbon dioxide because the research linking rising CO2 levels to rising temperatures is “not really conclusive if the two science groups can’t come together.”
The witness from Environmental Arizona responded, “I believe that it’s something like 98 percent of the scientists working on these issues agree that CO2 and greenhouse gases contribute. When you weigh 98 percent against the small amount of disagreement — it’s pretty clear,” he said.
A summary of climate research published by the National Aeronautics and Space Administration (NASA) concluded that 97 percent of climate scientists “agree that climate-warming trends over the past century are very likely due to human activities and most of the leading scientific organizations worldwide have issued public statements endorsing this position.”
Those organizations include the American Association for the Advancement of Science, the American Chemical Society, the American Geophysical Union, the American Medical Association, the American Meteorological Society, the American Physical Society and the Geological Society of America, the U.S. National Academy of Sciences, the U.S. Global Change Research Program, the International Panel on Climate Change and others.
NASA studies show that carbon dioxide levels have increased 38 percent since the start of the Industrial Revolution in 1750 and methane levels have increased by 148 percent, with the increase accelerating sharply in recent decades. Between 1906 and 2005, the average global surface temperature has risen between 1.1 and 1.6 degrees F.
A report posted on NASA’s Earth Observatory website projects an additional rise in temperatures of perhaps 4 to 12 degrees F by the end of this century according to projections based on climate models.
Crandell replied, “I’m not sure 98 percent of scientists actually agree,” but then shifted the topic to the impact of rising CO2 levels on plant growth.
Plants take in carbon dioxide, which helps drive photosynthesis through which the plants produce energy from sunlight. Studies in greenhouses have shown that plants grow faster and actually use less water when given extra CO2.
Some studies have suggested rising atmospheric CO2 levels could have an impact on plant and crop growth. For instance a study by researchers from Kansas State University linked the rise in carbon dioxide levels between 1958 and 1911 from 316 parts per million (ppm) to 390 ppm had partially compensated for a decline in winter wheat yields due to drought, according to a summary of the research on the Science Daily website.
Another Australian study published in Geophysical Research letters reported on the development of a mathematical model that estimated rising CO2 levels have boosted plant growth by 11 percent since 1982.
However, a variety of other studies suggest predicted higher average temperatures, shifts in the growing season and an increase in both droughts and soil-eroding flooding could all overwhelm any growth-enhancing effects of the CO2.
For instance, a decade-long analysis by NASA concluded that the rise in CO2 in the past decade enhanced plant growth in the Northern Hemisphere — but rising temperatures and drought in the Southern Hemisphere canceled out any gain.
Moreover, a study published in Nature showed that the carbon releases from the topics had become twice as sensitive to temperature changes over the past 50 years, probably in response to changes in the soil and heat stress on the plants.
A 1 degree rise in average temperatures in the tropics resulted in the release of an extra 2 billion tons of carbon dioxide into the atmosphere compared to 50 years ago, concluded the University of Exeter researchers.
Even in North America, forests have a limited capacity to absorb extra carbon dioxide in the atmosphere, according to an 11-year study by Northern Arizona University researchers published in the journal New Phytologist. The researchers fed an enriched CO2 diet to a stand of trees and other plants. They measured both the uptake of CO2 by leaves and the release of CO2 by decomposition. They observed that changes in the soil released more CO2 than the leaves absorbed. Therefore, the researchers concluded existing climate models have under-estimated the impact of rising CO2 levels.
A report published in New Scientist concluded many factors could overwhelm growth-inducing impact of rising CO2 levels, including drought, a shortage of nitrogen, acidification of the oceans, changes in rainfall patterns and other shifts.
A 20-year study in experimental plots in Panama and Malaysia recently determined that a 1 degree centigrade rise in temperature actually resulted in a 50 percent decrease in tree growth. The report cited estimates that the shift in average temperatures will result in plants and soils becoming net contributors to the rise in carbon dioxide, rather than a way to remove carbon dioxide through increased plant growth. That shift could contribute to the extinction of 20 to 30 percent of plant and animal species by the end of the century.
Finally, a rise in carbon dioxide levels could well lead to other surprising impacts — like a jump in the number of leaf-eating insects, according to a study by Penn State researchers, reported on the Science Daily website. Those researchers studied leaf fossils dating back 55 million years when atmospheric carbon dioxide levels tripled — apparently driven by the smoke from a massive surge in volcanic eruptions.
The percentage of leaves with serious insect damage rose from between 15 and 38 percent before the CO2 surge, jumped to 57 percent as CO2 levels rose, then dropped back down to 33 percent as CO2 levels again declined.
At the recent Senate hearing, Crandell said he believes we would benefit from increasing CO2 levels in the atmosphere.
“I think there’s evidence that people who use greenhouses, they pump carbon dioxide into the greenhouse. I’m not sure that the 98 percent of scientists you’re quoting have seen the research. Simple biology tells you about the carbon cycle. We’re going to starve to death ....”
“We’ve only recently decided to put lots of carbon dioxide into the atmosphere,” responded the witness cautiously.
“I’m not sure that’s necessarily true,” said Crandell. “I don’t think we can go back all the times that this Earth was being created and determine how much carbon dioxide was actually in the earth. There are a lot of things we just don’t know. To say we’re creating a whole lot more carbon dioxide, I’m not sure you can make that connection. I think we’re going to be here for a whole lot longer and the use of carbon dioxide to produce more food is more important than trying to limit the most important product in the formation of plant fiber — and that’s carbon dioxide.”