cations of atmospheric science, including the benefits of improved knowledge of atmospheric processes for the health and welfare of the environment and society.
As BASC studied the progress and future of the atmospheric sciences, it became evident that a critical contemporary theme involves the increasing importance of integrated observation systems and new observations of critical variables; thus, these constitute the subject of the Board's two highest-priority recommendations, designated as ''Imperatives.''
The atmospheric science community and relevant federal agencies should develop a specific plan for optimizing global observations of the atmosphere, oceans, and land. This plan should take into account requirements for monitoring weather, climate, and air quality and for providing the information needed to improve predictive numerical models used for weather, climate, atmospheric chemistry, air quality, and near-Earth space physics activities. The process should involve a continuous interaction between the research and operational communities and should delineate critical scientific and engineering issues. Proposed configurations of the national and international observing systems should be examined with the aid of observing system simulation experiments.
In addition, new opportunities for advances in research and services lead to the second imperative:
The federal agencies involved in atmospheric science should commit to a strategy, priorities, and a program for developing new capabilities for observing critical variables, including water in all its phases, wind, aerosols, and chemical constituents and variables related to phenomena in near-Earth space, all on spatial and temporal scales relevant to forecasts and applications. The possibilities for obtaining such observations should be considered in studying the optimum observing systems of Imperative 1.