Global Atmosphere Watch

Project Description
The purpose and long-term goal of the Global Atmosphere Watch (GAW), a program of the World Meteorological Organization (WMO) is to provide data, scientific assessments, and other information on the atmospheric composition and related physical characteristics of the background atmosphere from all parts of the globe. These are required to improve understanding of the behaviour of the atmosphere and its interactions with the oceans and the biosphere and will enable prediction of the future states of the earth-atmosphere system. GAW was established in 1989 as a coordinated system of networks of observing stations some of which began data-gathering in the 1950s and includes associated facilities and infrastructure encompassing measurement and related scientific assessment activities. The overall role of GAW is to supply basic information of known quality indicative of the atmospheric environment that transcends specific issues. The measurement programme includes: greenhouse gases, ozone (surface, total, and profile), radiation (including UV-B) and optical depth, precipitation chemistry, chemical and physical properties of aerosols, reactive gases, radionuclides, and related meteorological parameters. National and international policy decisions affecting the environment in the 21st century will thus rely heavily on the scientific data gathered through GAW. GAW is an integral part of the Global Climate Observing System (GCOS) consisting of global stations located at remote pristine locations and regional stations for characterizing the regional environmental quality away from direct pollution sources. Also established are WMO World Data Centres for ozone and UV-B, radiation, aerosol optical depth, precipitation chemistry, greenhouse gases and all atmospheric gases except ozone, and aerosols. A concept of Quality Assurance/Science Activity Centres serves as a crucial link between the individual sampling sites - where the parameters are measured - and the ultimate data depositories (Data Centres) where the quality-assured data are archived and distributed.

For more information see:
http://www.wmo.ch/web/arep/gaw/gaw_home.html