Chemist, Developers Test Tool for Assessing Marine Damage

Scripps Institution of Oceanography at UC San Diego marine chemist Andrew Dickson plans to purchase and deploy an autonomous buoy-mounted sensor to study the effect increasingly acidic ocean water could be having on ecosystems in the California Current.

Andrew Dickson, a marine chemist at the University of California-San Diego's Scripps Institution of Oceanography, is collaborating with Montana-based developers of a sensor that may help uncover the effect of acidic ocean water on ecosystems in the California Current.

The Missoula, Mont., firm Sunburst Sensors and University of Montana researcher Mike DeGrandpre developed the instrument, with input from other researchers including Dickson, who helped them run tests on the instrument. In June, they received a $980,000 federal grant to further develop the sensor.

Recent findings have indicate a disturbing upwelling of acidic waters into coastal regions that support sea urchins, abalone, and other marine invertebrates whose ability to form shells could be impaired by the corrosive water.

"If the instrument works as we hope, it will be a valuable tool that will enable us to characterize the extent and intensity of incursions of these high-CO2 [carbon dioxide] waters onto the California shelf and better understand the stresses ecosystems are under," said Dickson.

The device, known as a Submersible Autonomous Moored Instrument, is mounted onto buoys and suspended at a depth of up to several hundred meters, where it measures pH for long periods of time. "By observing pH over long time periods, ocean scientists will be able to determine the processes that control seawater pH, its natural range of variability, and how pH is changing as CO2 is absorbed by the oceans," DeGrandpre said.