UH scientists
Star-Bulletin staff
co-author new theory
on global warmingUniversity of Hawaii scientists collaborated with other researchers on new information concerning global warming, which was published in the March 3 issue of the weekly journal Science.
The scientists developed a theoretical model describing the concentrations of carbon dioxide and oxygen in the atmosphere over the past 560 million years, which may provide the clues in predicting how the atmosphere will respond to human activities such as burning fossil fuels and deforestation.
"There is great concern over the possible effects on Earth's climate by the accumulation of carbon dioxide in the atmosphere due to fossil fuel burning," said UH professor Edward Laws, one of the paper's co-authors.
The paper focused on the biological interaction between oxygen and carbon dioxide, which arises because oxygen affects the metabolism of carbon dioxide by plants, resulting from a process called photorespiration.
The UH scientists studied marine algae in a laboratory, regulating the concentrations of carbon dioxide and oxygen in the algae's culture system, then explored the impact of oxygen on its carbon dioxide metabolism.
Using information from UH and other results, Robert Berner of Yale University developed a model of oxygen concentrations in the atmosphere over the past 560 million years.
The model complements earlier work that described carbon-dioxide concentrations rising dramatically in oxygen concentrations to about twice present-day amounts about 300 million years ago.
"Interestingly, this period of elevated oxygen concentrations is associated with the rise of insect gigantism developed in the fossil record," Laws says.
"For example, during that time there evolved dragonflies with wingspans of . . . more than two feet. This is probably due to the well-known enhancement of flight metabolism in arthropods by elevated oxygen concentrations.
University of Hawaii