Short-term measurements of carbon dioxide, water, and energy fluxes were collected at four locations along a mean annual precipitation gradient in southern Africa during the SAFARI 2000 wet (growing) season campaign of 2000. The purpose of this research was to determine how observed vegetation-atmosphere exchange properties are functionally related to long-term climatic conditions. This research was conducted along the Kalahari Transect (KT), one in the global set of International Geosphere-Biosphere Programme (IGBP) transects, which covers a north-south aridity gradient, all on a homogenous sand formation. Eddy covariance instruments were deployed on a permanent tower in Mongu, Zambia (879 mm of rainfall per year), as well as on a portable tower in Maun (460 mm/yr), Okwa River Crossing (407 mm/yr), and Tshane (365 mm/yr), Botswana for several days at each site.The data files are stored as ASCII text files, one file per site, in comma-separated-value (csv) format, with column headers. Each file contains measurements of the following parameters: air temperature; CO2 concentration; CO2 flux; friction velocity; heat flux; infrared surface skin temperature; longwave radiation; net radiation; photosynthetic photon flux density; photosynthesis energy; relative humidity; shortwave radiation; soil moisture; soil temperature; vapor pressure deficit; wind speed and angle; water use efficiency; and water vapor. Additional information can be found in the companion file: ftp://daac.ornl.gov/data/safari2k/climate_meteorology/kalahari_co2_heat… kt_co2_heat_flux_readme.pdf. Detailed photographs (.jpg) that complement the experimental descriptions for this data set are available on the S2K Photo Gallery pages.