The Southern African Regional Science Initiative - SAFARI 2000 - is an international science initiative aimed at developing a better understanding of the southern African earth-atmosphere-human system. Initial plans for SAFARI 2000 were developed in June and July 1998 at workshops involving scientists from southern Africa, the United States and Europe. These plans have been refined at subsequent workshops held in the United States and Southern Africa, in May and July 1999, respectively.

The goal of SAFARI 2000 is to identify and understand the relationships between the physical, chemical, biological and anthropogenic processes that underlie the biogeophysical and biogeochemical systems of southern Africa. Particular emphasis will be placed upon biogenic, pyrogenic and anthropogenic emissions, their characterization and quantification, their transport and transformations in the atmosphere, their influence on regional climate and meteorology, their eventual deposition, and the effects of this deposition on ecosystems. To accomplish this, participants will:

• integrate remote sensing, computational modeling, airborne sampling and ground-based studies;
• link the biological, physical and chemical components of the regional ecosystems by integrating them within the semi-closed atmospheric gyre persistent over the region;
• combine the expertise and knowledge base of regional and international scientists.

SAFARI 2000 builds upon the success of the Southern African Fire-Atmosphere Research Initiative in 1992 (SAFARI-92). SAFARI-92 showed that a) it is feasible to characterize, quantify and validate estimates of regional emissions, and b) critical gaps remain in our understanding of the fate and impacts of the emissions on the functioning of the regional land-atmosphere systems.

Programmatically, SAFARI 2000 is an organizational umbrella designed to maximize the overall efficiency and effectiveness of a group of various environmental studies occurring between 1999 to 2001. The studies range from those still in their foundational stage to those which are long-term monitoring efforts.

SAFARI 2000 encompasses the following science elements: terrestrial ecology and land processes; land cover and land use change; aerosols; trace gases; clouds and radiation; hydrology; and modeling. These elements will be studied using ground and airborne measurements complemented by remote sensing observations from a new generation of earth observation satellites, including NASA’s Terra, Aqua (formerly PM), Earth Observing-1 (EO-1), Vegetation Canopy LIDAR (VCL), Landsat 7 and TRMM platforms, as well as the European ENVISAT and POLDER II satellites. Data from existing sensors, e.g., NOAA polar orbiters (AVHRR) and METEOSAT, will likewise be employed. In turn, ground- and aircraft-based measurements from SAFARI 2000 will help validate the remotely sensed satellite observations.

The SAFARI initiative includes continuous efforts as well as intense, episodic field campaigns as identified in Table 1.

Table 1. Intensive Field Campaigns
Period	Season	Primary Goal
August-September 1999	dry	identify and quantify major dry-season sources of emissions including those from biomass burning, land use, and industry, prototype ground-based and airborne measurement techniques, characterize incoming radiation, boundary layer profiling, determine spectral characteristics of vegetation
February-March 2000	wet	identify and quantify major wet season sources of emissions (e.g. CH4 from wetlands and NMHC from plants), examine ecosystem structure, functioning and processes at peak biomass, collect data to calibrate and initialize ecosystem models at point, local and regional scales, determine spectral characteristics of vegetation
August-September 2000	dry	track the movement, transformations, and deposition of dry-season emissions from biomass burning and other sources, quantify burnt area

Each successive campaign is expected to both draw increased international participation and to increase in the scope of scientific questions addressed. The campaigns will allow scientists to leverage their modeling efforts upon existing ground-based and atmospheric monitoring networks, as well as new airborne and remote sensing measurements. Ground-based efforts will be co-ordinated to maximize sampling effectiveness and efficiency, as well as facilitate collaboration and data synthesis. Meteorological and remote sensing measurements will be collected throughout the initiative. The international science networks supporting efforts in the region (e.g., those of IGBP and START) will help broaden African scientific involvement.

Results from SAFARI 2000 are expected to contribute to the development of improved policies and practices affecting the environment. They should also help local officials gain insight into global change on a regional scale and understand potential impacts from global change international environmental treaties. Regional scientists will benefit through heightened recognition, enhanced capacity, and the transfer of technology. The relevance of the scientific results will be discussed through a series of workshops. One such workshop, the Policy Dialogue Workshop on Ecological Impacts of Trans-boundary Air Pollution in Southern Africa, organised by the Air Pollution Impacts Network for Africa (APINA), has already been held. SAFARI 2000 has an open internal and external data sharing policy. Information will be disseminated regionally and internationally via the internet as well as through the distribution of CD-ROMS and magnetic tapes. We anticipate that a long-term data archive will be developed such that data and models can serve the community well into the 21 st century.