Small marine organisms can impact world's climate
Washington: Scientists including one of Indian origin have showed that warmer ocean temperatures could alter populations of phytoplankton and thus have an impact on climate change.
By the end of the 21st century, warmer oceans will cause populations of these marine microorganisms to thrive near the poles and may shrink in equatorial waters, researchers from Michigan State University said.
Since phytoplankton play a key role in the food chain and the world’s cycles of carbon, nitrogen, phosphorous and other elements, a drastic drop could have measurable consequences.
Phytoplankton also play a key role in regulating atmospheric carbon dioxide levels, and thus global climate, so the shift could cause significant change, the researchers said.
“In the tropical oceans, we are predicting a 40 percent drop in potential diversity,” said Mridul Thomas, MSU graduate student and one of the co-authors.
“If the oceans continue to warm as predicted, there will be a sharp decline in the diversity of phytoplankton in tropical waters and a poleward shift in species’ thermal niches, if they don’t adapt to climate change.”
Although phytoplankton are small, they flourish in every ocean, consuming as much carbon dioxide through photosynthesis as all the terrestrial plants combined.
Being able to forecast the impact of these changes will be a useful tool for scientists around the world, said David Garrison, program director in the National Science Foundation Division of Ocean Sciences.
“This is an important contribution to predicting plankton productivity and community structure in the oceans of the future,” he said. “The work addresses how phytoplankton species are affected by a changing environment, and the really difficult question of whether evolutionary adaptation to those changes is possible.”
The study has been published in the current issue of Science Express.