Climate change has major impact on oceans

“Instead of facing the end of these critical missions and becoming blind to the changes occurring in our oceans,” Behrenfeld said, “we should be building even better ones to see more clearly than we have in the past, and to gauge the potential consequences of climate change on ocean productivity.”

The panelists also called for greater investment in ocean observing systems that would allow scientists to better measure changing in the ocean ecosystem, including large-scale circulation and coastal upwelling systems around the world. Klaus Keller of Penn State University reported on the economic costs and benefits of effective ocean observing systems to detect changes in the north Atlantic Meridional Overturning Circulation.

Jack Barth, an oceanographer at Oregon State University, reported on the hypoxia events that have plagued the Pacific Northwest coast since 2000. These low-oxygen zones in the near-shore are unprecedented over the last five decades of scientific observation and likely linked to stronger, more persistent winds that are expected to occur with global warming. The California Current System provides a case study for similar changes in coastal upwelling zones off South America, southern Africa and northern Africa, Barth said.

“One of the things we’ve observed is how wind patterns have changed and greatly affected upwelling,” Barth said. “Two decades ago, the winds would last for three or four days, and then subside. Now they persist for 20 to 40 days before settling down. This creates significant impacts on upwelling and biological productivity, but these impacts can swing wildly from one extreme to another and have been difficult to predict.”

The AAAS symposium was organized by the Partnership for Interdisciplinary Studies of Coastal Oceans, a multi-university research effort headquartered at Oregon State University and funded by the David and Lucile Packard Foundation, the Gordon and Betty Moore Foundation, the National Science Foundation and other sources.