IGACtivities Article

Issue No. 15, December 1998

SAFARI-2000: A Southern African Regional Science Initiative

Contributed by:
Bob Swap, University of Virginai; Harold Annegarn, Univeristy of Witwaterstrand, South Africa; Mary Scholes, Univeristy of Witwaterstrand, South Africa; and Chris Justice, University of Virginia

Abstract

SAFARI 2000, currently in its planning phase, is an international, collaborative science initiative whose purpose is to understand the operation of the southern African biogeophysical system as an integrated, interconnected system. Key linkages between physical, chemical, biological, and anthropogenic processes essential to the functioning of the biogeophysical system will be examined. SAFARI 2000 includes the following science components: terrestrial ecosystems and biogeochemical modeling; land-cover and land-use change mapping, monitoring, and modeling; fire disturbance studies; quantification and modeling of pyrogenic, biogenic, and industrial emissions and their transport; aerosol and cloud characterization and their interactions; atmospheric chemistry and modeling and atmospheric deposition studies. Of particular interest to the IGAC community is the SAFARI 2000 focus on aerosols and trace gases, especially with respect to sources, transformations, patterns, responses and processes.


SAFARI 2000 follows on the success and builds upon the scientific legacy of SAFARI-92. SAFARI-92 focused on developing the fundamental understanding of biomass burning processes in a subtropical savanna, but stopped short of fully exploring the consequences of these processes. More importantly, perhaps, SAFARI 92 established a basis for international collaboration among scientists working across many different disciplines. It is on this foundation that SAFARI 2000 is being developed. SAFARI 2000 will take the next step and apply findings to determine many of the consequences of biomass burning and other processes associated with regional land cover and land use changes to the ecosystems of southern Africa.


The initial motivation for a post-SAFARI 92 research initiative originated with a number of regional planning meetings and documents that identified global change science priorities for the Southern African Region (e.g., IGBP Report 31, IGBP Report 41, IGBP Report 42 and the START Regional Workshop on Global Changes, Gaborone, 1994; IGBP Miombo Workshop, Lusaka, 1997). SAFARI 2000 emerged as a tractable regional science initiative during a series of stakeholder workshops held during June and July 1998. At a U.S. NSF-sponsored workshop on Southern African Land/Atmosphere/Biosphere Interactions, that was held on July 11­17, 1998, in Blydpoort, Mpumalanga, South Africa, some 70 participants from 12 countries came together to discuss and develop SAFARI 2000. Much like its predecessor, the IGAC/BIBEX-SAFARI 92 program, SAFARI-2000 is a confederation of affiliated national, regional, and global environmental change research efforts that have secured their own funding and are currently underway or will be undertaken soon in the southern African region. NASA, through its EOS, Land Cover and Land Use Change, and Terrestrial Ecology Programs is supporting a number of ongoing research efforts within the southern African region that will contribute to SAFARI 2000.


Additionally, a strong satellite data product validation component associated with the launch of NASA's Earth Observing System (EOS) AM-1 platform in 1999 and other new sensing systems will be undertaken in the context of these science activities. Validated remotely sensed data products will be provided as inputs to the above studies.


SAFARI 2000 will be conducted over a three-year period starting in the second half of 1999 with major field campaigns during 1999 and 2000. SAFARI 2000 will utilize field sites that are representative of major regional land cover variants, have a scientific heritage and that are subjected to long-term preservation. The two key sites are Mongu, Western Province, Zambia and Skukuza, Kruger National Park, South Africa. Based on lessons learned from previous regional field campaigns, post-field campaign data integration is actively being planned. A synthesis of results will be available in 2001. SAFARI 2000 will add scientific value by enabling the synthesis and coordination between these different activities within the region, providing a basis for budget closure experiments and a contribution to a regional science assessment of global change. The international regional science networks, developed over the years within the region through IGBP and START, will participate in the initiative, providing the mechanism for broad African scientific involvement. START is supporting this critical component of SAFARI 2000.

Introduction

In 1992 IGAC-BIBEX undertook the Southern Africa Fire-Atmosphere Research Initiative (SAFARI) 1992 (1). SAFARI-92 focused on the factors controlling the process and distribution of biomass burning as well as the chemistry, transport and source strength of the products of biomass burning (2). SAFARI-92 established much of the understanding of the fundamental biomass burning processes in a subtropical savanna, but was only minimally dedicated to the consequences of these processes. SAFARI-92 involved over 150 scientists from 14 countries and focused on observations related to African savanna fires and their atmospheric effects in the southern hemisphere. During SAFARI several partnerships were developed between international scientists studying land - atmosphere interactions. The continued development of these relationships has culminated in the proposed SAFARI 2000 experiment. SAFARI was chosen as a rallying acronym for the initiative, centered on the millennium and with a heritage of international collaboration within the region. The project initiated by a core group of collaborating scientists has received preliminary endorsement from the IGAC BIBEX group. The outline of the SAFARI 2000 Science Plan, developed at the planning meeting at Blydepoort, Mpumalanga, South Africa (July 10-20, 1998), has been presented for endorsement at the BIBEX Meeting held during the CACGP-IGAC Joint Symposium in Seattle, USA (August 22, 1998). The Science Plan will go before the IGAC steering committee in early 1999. SAFARI 2000 will follow the model of the SCAR-B (Smoke Cloud Aerosol and Radiation) experiment (3) also undertaken in the BIBEX framework, combining satellite, aircraft and in situ experiments but with stronger terrestrial ecosystems, land cover and land use change and satellite validation components.

Central and southern Africa have undergone and continue to undergo large changes in social, economic, and political environments that contribute to large-scale changes in land use and land cover within their respective ecosystems. The opening up of southern Africa due to the absence of war and political strife has led to economic development, especially in the sector of heavy industry. Energy generation to drive mining and metallurgical industries, as well as the industrial processes themselves, contribute to high levels of aerosol and trace gas emissions (4, 5). Additionally, this region of Africa is subjected to some of the most extensive biomass burning in the world, most of which is associated with human population pressures on regional ecosystems (6, 7, 8, 9). These anthropogenic perturbations, along with a strong source of biogenic emissions (10, 11, 12, 13) and a large natural variability in both regional climate and ecosystem processes combine, primarily through manipulation of surface aerosol and trace gas emissions, to effect changes in the biogeochemical cycling of the region.
Much progress has been made recently through international scientific research concerning changes in land cover and land usage, atmospheric circulation and transport, biogeochemistry, and ecosystem functioning, in southern and central Africa. The implementation of the IGBP Terrestrial Transects program (14), the creation of the IGBP Miombo network (15) and the IGBP LUCC/DIS/START Miombo CD-ROM, the IGBP Kalahari Transect (16), the IGBP BIBEX (Biomass Burning Experiment) SAFARI/TRACE-A field campaigns (1, 2, 17), the formation of the Southern African Atmospheric Research Initiative (SAARI) alliance as well as the involvement of IGAC's Biosphere-Atmosphere Trace Gas Exchange in the Tropics (BATGE; 18, 13) and Deposition of Biogeochemically Important Trace Species (DEBITS) programs within the region, are all examples of such progress within the IGBP.

Although these projects have all contributed to the understanding of discipline- specific objectives, exploration of linkages between and the integration of information from each of the programs to form a more complete and interdisciplinary understanding of the functioning of southern and central African ecosystems and the regional atmosphere has been given less attention. It is envisaged that by international collaboration through SAFARI 2000, new in situ data collection combined with advances in the modeling of the bio-geophysical systems and improvements in satellite monitoring, will lead to an improved understanding of regional and global environmental change in southern Africa.

Research Objectives

The goal of SAFARI 2000 is to understand the key linkages between the physical, chemical and biological processes, including human impacts, essential to the functioning of the southern African biogeophysical system. Broadly, SAFARI-2000 aims to: characterize and quantify the biogenic, pyrogenic and anthropogenic aerosol and trace gas sources and sinks in southern Africa; validate these observations using atmospheric transport and chemistry models, ground-based, air-borne, and satellite-based observations; and determine the climatic, hydrological, and ecosystem consequences of these biogeochemical processes. Specific questions about aerosols and trace gases were developed at the Blydepoort workshop with the following scientific progression in mind: sources; transformations; patterns; responses; and interactive processes.

To this end, SAFARI 2000 will exploit current and planned regional remote sensing, modeling, airborne and ground-based environmental studies, as well as combine the expertise and knowledge base of regional and international scientists. This will involve the use of models that integrate in situ observations of ecosystem processes such as biophysical energy and water exchanges with the atmosphere, biogeochemical cycling, and plant demographics. The observations and modeling will extend across spatial scales from plot to landscape and region scales and across time scales from hours to weeks to years. An important component of the SAFARI 2000 objectives is model and satellite product evaluation by local experts, as well as the promotion of informed use of these models and data by regional scientists. Special attention is being given to data access and timeliness of data availability. Information from SAFARI 2000 activities will be disseminated regionally and internationally via the internet as well as through the distribution of CD-ROMs. IGBP-DIS will assist in facilitating the access to and management of the data associated with this regional research initiative.

Science Rationale for the Initiative

Southern Africa, targeted as an Inter-governmental Panel for Climate Change (IPCC) science assessment focus region, is an area where global change, in the form of increasing population and population migration, industrial development, vulnerability of rain-fed subsistence agriculture, poor economic resilience, water and food availability, and trans-boundary developmental issues, is very likely to have a large impact on the biogeophysical functioning of the region. Results of the SAFARI-92 and SA'ARI-94 (19, 20) field campaigns have led to the formulation of questions, many of which are unanswered, that require a more synthetic, integrated and interdisciplinary research.

With respect to the tractability of the proposed research, the atmospheric environment, with clearly defined inflow and outflow regions, and the geography of Africa south of the Equator permit a reasonably discrete study region, which in turn permits mass-balance calculations to be performed. The semi-closed atmospheric circulation provides both a context and integrating mechanism for between the living and physical systems. This is especially the case during austral winter when anticyclonic circulation and associated clear sky conditions favorable for satellite and airborne remote sensing, dominate the region on as many as four out of every five days (21, 22). It will be possible to conduct a closed experiment within southern African that is focused on the characterization of biogeochemical and biogeophysical in-flow and outflows to the region. The existing regional scientific database, when combined with the regional scientific and logistic base, provides the framework necessary for conducting SAFARI 2000.

Way Forward and Next Steps

Numerous government and scientific agencies from the U.S., Europe and Southern Africa have been briefed on the development of SAFARI 2000. The science plan is currently being developed and should be ready for wide distribution early 1999. SAFARI 2000 will be conducted over a three-year period starting in 1999 with both intensive ground and flying field campaigns during 1999 and 2000. Three intensive flying campaigns, with each successive campaign increasing in the level of international collaboration, are scheduled: August­September 1999: dry season, biomass burning campaign; February­March, 2000: wet season campaign; August­September 2000: dry season biomass burning campaign. Intensive ground-based efforts will also be coordinated to maximize overlap in the observations. The whole campaign will be supported by intensive meteorological measurements.

The SAFARI 2000 initiative is open to international participation to help achieve its regional research objectives.

References and Notes
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