Page Quinton
verified evidence suggesting carbon dioxide decreased
significantly at
the end of the Ordovician Period, 450 million years ago,
preceding an ice
age and eventual mass extinction. These results will
help
climatologists better predict future environmental changes.
Carbon cycling research can help scientists predict global
warming and cooling trends
(October 10, 2015) Making
predictions about climate variability often means looking to the past to find
trends. Now paleoclimate researchers from the University of Missouri have found
clues in exposed bedrock alongside an Alabama highway that could help forecast
climate variability. In their study, the researchers verified evidence
suggesting carbon dioxide decreased significantly at the end of the Ordovician
Period, 450 million years ago, preceding an ice age and eventual mass
extinction. These results will help climatologists better predict future
environmental changes.
The Ordovician geologic period included a climate
characterized by high atmospheric carbon dioxide (CO2) levels, warm average
temperatures and flourishing life. Near the end of the period, CO2 levels
dropped significantly but precisely when and how fast is poorly known. Kenneth
MacLeod, a professor in the Department of Geological Sciences in the MU College
of Arts and Science, directed a research team studying the climate changes 450
million years ago to better understand the interactions among the biosphere,
the oceans, atmospheric CO2 levels, and temperature.
“Climate is not a simple science; many small factors
determine what exactly leads to global warming and cooling trends,” MacLeod
said. “By understanding the deep past, we have better information about
historic trends that lead to better predictions. Understanding carbon cycles
adds value to our knowledge base of climate change.”
During the Late Ordovician period, most of North America was
covered in a shallow tropical sea. What is now Alabama was on the margin of
that sea where local environmental effects likely did significantly impact
carbon cycling. Page Quinton, a doctoral student in MU’s geological sciences
program, led a field research team in northeastern Alabama that collected rock
samples from rock formations exposed when workers cut highways through hills in
the region. Using the samples, Quinton analyzed them for chemical clues that
can be related to CO2 levels at specific time periods.