Aerosol Workshop — June 2-3, 1997
Panel D: Agency Plans
R. Curran, J. Levy, J. Moyers, R. Petty, R. Ferek
Curran summarized the NASA Strategy to Address the Effects of Aerosols on the Global Environment, which is an appendix to the NASA Science Research Plan. NASA already has substantial aerosol research which includes consideration of both climatic and chemical aerosol effects, and including both stratospheric and tropospheric aerosols. NASA's aerosol research is supported primarily by the Office of Mission To Planet Earth (MTPE), specifically by: 1) science division research and analysis programs and EOS interdisciplinary investigations, 2) flight mission project science support [presently UARS, SAGE, TOMS and EOS], and 3) focused research to understand the impact of aircraft on the environment, jointly sponsored with the Office of Aeronautics.
The present workshop is intended to help define a focused initiative that would improve understanding of radiative forcing caused by aerosols. This initiative would be coordinated with and draw upon the aerosol research already sponsored by NASA. It would be expected to make effective use of the relevant global satellite measurements and interdisciplinary investigations supported by NASA. Because of the complex and subtle ways that aerosols can influence climate, a successful research program will undoubtedly require cooperation among federal agencies and also international cooperation.
Levy summarized the Aerosol Program within the Climate and Global Change Program of the National Oceanic and Atmospheric Administration (NOAA). The objective of this program is predictive understanding of the influence of tropospheric aerosols on the Earth's chemical and radiative balance, with a view towards the following near-term information needs: 1) attribution of climate change (Have you seen anything yet? - unmasking the greenhouse gas signal), 2) prediction of future climate scenarios ("What are our best options?"). The expected deliverable is improved detection/attribution/prediction for IPCC (2000).
The goals are 1) reduced uncertainty in the (calculated) magnitude and geographical distribution of radiative forcing due to aerosols, obtained via long-term monitoring of chemical, physical, and optical properties at selected sites, closure studies as part of intensive field campaigns, monitoring, and laboratory studies, and modeling, 2) improved understanding of the processes that link emissions of aerosols precursors to the spatial distributions, abundances, and properties of aerosols obtained via field measurements (ground, air, ship, satellite) and modeling. Among these activities monitoring at selected sites field measurements from ships are NOAA specialties.
The objectives of the NOAA Aerosols Program are central to the objectives of the current workshop. But possible NOAA contributions are constrained by the level of support for this program, which is $1M per year and is not expected to increase.
Petty summarized the Department of Energy's aerosol research program, which is sponsored by its Atmospheric Chemistry Program (ACP), Atmospheric Radiation Measurement (ARM) program, and the National Institute on Global Environmental Change (NIGEC). DOE specifically supports research to understand the fundamental scientific phenomena associated with aerosol radiative forcing and climate change.
These studies are expected to include research on aerosol forcing of climate that advances knowledge in the representation of aerosols in global climate models, particularly with respect to indirect climate effects; laboratory and theoretical research on aerosol optical properties; identification of aerosol molecular composition particularly the organic fraction; development of an understanding of aerosol formation and growth in the atmosphere; studies elucidating the aerosol-CCN-cloud droplet-albedo relationship; execution of atmosphere closure experiments to test theoretical understanding; application of instrumentation technology for measuring aerosol properties in situ; and system integration and assessment utilizing sensitivity/uncertainty analyses.
The DOE research agenda is central to objectives of the current workshop. But new contributions by DOE are constrained by research budgets that are expected to at best hold steady.
Ferek summarized the aerosol research of the Office on Naval Research which is funded within three programs: Marine Meteorology and Atmospheric Effects (322MM), Environmental Optics (322OP), and Biological and Chemical Oceanography (322BC). The Navy's interests lie primarily in the effects of aerosols on propagation of electro-optical radiation (visible and infrared). While not specifically driven by the issue of aerosol radiative forcing, much of the same physics is involved, particularly with fine particles and visible radiation. Specific interests, somewhat special to the Navy but overlapping with the other agencies' interests in the direct forcing issue, involve marine and coastal aerosols, near-surface natural and anthropogenic aerosols, desert dust in coastal regions, retrieval of boundary layer aerosol properties by remote sensing, and effects of coarse mode, short-lived aerosols on infrared wavelengths. ONR seeks to develop a predictive capability which will require at least four components to achieve success: model initialization (perhaps through remote sensing techniques), aerosol transport modeling (currently an active area of research using operational Navy meteorological models), aerosol process modeling (incorporating physical and chemical transformations), and extinction calculations across the range of wavelengths from the visible to infrared.
The funding available for basic aerosol research is currently about $1.4M per year, but the program is constrained by decreasing Department of Defense funding of basic R&D, and it has declined about 10% per year for the last two years. Funding appears likely to remain level or decrease slightly for the next several years.