New Oceanographic Buoy for Monitoring Sea Surface CO2

Mutsu Institute for Oceanography, a branch laboratory of Japan Agency for Marine-Earth Science and Technology, announced on June 28, 2007, that it had developed a new automatic monitoring oceanographic buoy system and began testing its performance in the equatorial zone of the tropical Pacific. The new drifting buoy system measures carbon dioxide (CO2) pressure in surface ocean water to obtain more precise data on the global distribution of CO2 fluxes between atmosphere and ocean.

Oceans cover about 70 percent of the earth's surface and store about 60 times the amount of CO2 in the atmosphere. To obtain detailed data on oceanic CO2, a monitoring network needs improvements including development of research satellites and automatic oceanographic buoys in addition to the conventional observation by research vessels.

The new buoy is small and light-weight, at 50 centimeters in height and about 15 kilograms in weight. The buoy uses a spectroscopic method to observe change in pH values in water samples, using a liquid-liquid equilibrium system, to provide equal CO2 concentrations in the seawater and the solution. This method will make it possible to run long-term unmanned observations. To reduce environmental impacts, light-emitting diodes (LEDs) were used as the sensor light source in order to reduce power consumption, and copper and silicon resin were used in anti-foulant coatings.

A trial on June 20, 2007 resulted in a successful automatic measurement of CO2 pressure in surface seawater and data transmission via satellite. The institute will continue test observations until July 2008 to monitor deterioration and durability of the buoy system as well as to keep track of the buoy's condition over time. The institute intends to analyze the collected data in detail later.

http://www.jamstec.go.jp/e/index.html

Posted: 2007/10/27 04:02:59 PM
Japanese version