ARL News

Precipitation Chemistry – World-wide


November 21, 2005

The chemical composition of rainfall reflects the quality of the air from which it falls. Consequently, changes in precipitation chemistry are useful indicators of trends in air chemistry. Furthermore, the chemicals carried by the rain can affect ecosystems, sometimes positively but usually negatively. For these reasons, measurements of precipitation chemistry have been a standard feature of many national monitoring programs. To integrate data from the various sources has proved tricky, because until about ten years ago there was no consistent effort to apply quality control on data originating from a large variety of national measurement programs, many in third-world countries.

In view of the obvious utility of such data, and in recognition of the need to impose some global standards and universal quality control, the World Meteorological Organization’s Global Atmosphere Watch organized a Precipitation Chemistry Quality Control and Science Activities Center. The Center was set up at the State University of New York, in Albany. Because of the long-standing interest of the Air Resources Laboratory in issues related to the interaction of the atmosphere with the rest of the environment, the QA/SAC has been structured as an ARL program. Sponsorship of it is by NOAA.

In the coming year, the activities of the QA/SAC are to be consolidated with the National Atmospheric Deposition Program (NADP), a nationwide US precipitation chemistry research network led by the Illinois State Water Survey. A global data base is to be generated, and the quality control efforts are to be refined. ARL will remain the point of interaction with NOAA and the WMO.

Contact information: Bruce B. Hicks
Phone: (301) 713-0684