To investigate potential contributions of savanna ecosystems to the Earth's carbon balance, an eddy covariance system was used to measure the seasonal variation in carbon dioxide, water vapor, and energy flux at the Maun micrometerological tower site in a broadleaf semi-arid savanna in Southern Africa, approximately 20 km east of Maun in northeastern Botswana. The open woodland studied consists of an overstory dominated by Colophospermum mopane with a sparse understory of grasses and herbs. Measurements presented in this data set cover the wet and dry season periods that coincided with field activities of the SAFARI 2000 project in February-April and August-September, 2000, respectively.
The data files contain numeric values that represent 30-minute averages from instrumentation mounted on the Maun tower. The parameters measured, or derived from measurements, include: air pressure, air temperature, albedo, carbon dioxide flux, dewpoint temperature, friction velocity, latent heat flux, longwave radiation, net radiation, precipitation, relative humidity, sensible heat flux, shortwave radiation, soil moisture, soil temperature, specific humidity, vapor pressure, and wind speed. The data files are stored as ASCII table files, one file per month, in comma-separated-value (.csv) format, with column headers.
Long term climatic data of the Maun area (monthly rainfall, maximum recorded monthly rainfall, mean maximum daily temperature, mean minimum daily temperature, and potential evapotranspiration) are provided, along with data set documentation, in the companion file: http://daac.ornl.gov/daacdata/safari2k/climate_meteorology/maun_met_flux/comp/maun_met_flux_readme.pdf.
Cite this data set as follows:
Lloyd, J., O. Kolle, E. Veenendaal, A. Arneth, and P. Wolski. 2004. SAFARI 2000 Meteorological and Flux Tower Measurements in Maun, Botswana, 2000. Data set. Available on-line [http://daac.ornl.gov/] from Oak Ridge National Laboratory Distributed Active Archive Center, Oak Ridge, Tennessee, U.S.A. doi:10.3334/ORNLDAAC/760.
Bird, M. I., E. M. Veenendaal, and J. Lloyd. 2004. Soil carbon inventories and delta C-13 along a moisture gradient in Botswana. Global Change Biology, 10(3): 342-349.
Greenberg, J. P., A. Guenther, P. Harley, L. Otter, E. M. Veenendaal, C. N. Hewitt, A. E. James, and S. M. Owen. 2003. Eddy flux and leaf-level measurements of biogenic VOC emissions from mopane woodland of Botswana. J. Geophys. Res., 108(D13), 8466, doi:10.1029/2002JD002317.
Veenendaal, E. M., O. Kolle, and J. Lloyd. 2004. Seasonal variation in energy fluxes and carbon dioxide exchange for a broad-leaved semi-arid savanna (Mopane woodland) in Southern Africa. Global Change Biology 10(3): 309-317.
The data files contain numeric values that represent 30 minute averages from instrumentation mounted on the Maun tower for February-April and August-September, 2000. The data files are stored as ASCII table files, one file per month, in comma-separated-value (.csv) format, with column headers. The files are:
maun_met_flux_2000-02.csv
maun_met_flux_2000-03.csv
maun_met_flux_2000-04.csv
maun_met_flux_2000-08.csv
maun_met_flux_2000-09.csv
Missing data values are represented by a value of -9999. The content of the data files are described below.
| Column Name | Column Description | Units |
|---|---|---|
| Date | Date of measurement | dd-mon-yyyy |
| Time | Time at end of 30-min measurement period | hh:mm UTC |
| p | Air pressure | mbar |
| T | Air temperature (tower top) | degrees Celsius |
| Tpot | Potential temperature | K |
| Tdew | Dew point temperature | degrees Celsius |
| rh | Relative humidity | % |
| VPmax | Vapor pressure maximum | mbar |
| VPact | Vapor pressure actual | mbar |
| VPdef | Vapor pressure deficit | mbar |
| sh | Specific humidity | g kg-1 |
| H2O C | Water vapor concentration | mmol mol-1 |
| rho | Density | g m-3 |
| vhor_cup | Horizontal windspeed, measured by cup anemometer | m s-1 |
| vhor_sonic | Horizontal windspeed, measured by sonic | m s-1 |
| H | Sensible heat | W m-2 |
| LE | Latent heat | W m-2 |
| E | Water vapor flux | mmol |
| C | CO2 Flux | µmol m-2 s-1 |
| U* | Friction velocity | m s-1 |
| corr. LE | corrected Latent exchange | W m-2 |
| corr. E | corrected Latent exchange | mmol |
| corr. C | corrected Latent exchange | µmol m-2 s-1 |
| rain | Precipitation | mm |
| Srain | Sum precipitation | mm |
| Tpyr | Temperature, pyranometer | degrees Celsius |
| TDR | Total downward radiation | W m-2 |
| TUR | Total downward radiation | W m-2 |
| SWDR | Shortwave downward radiation | W m-2 |
| SWUR | Shortwave upward radiation | W m-2 |
| Albedo | Albedo | % |
| LWDR | Longwave downward radiation | W m-2 |
| LWUR | Longwave upward radiation | W m-2 |
| TRAD | Temperature radiometer | degrees Celsius |
| PAR | Photosynthetically active radiation | µmol m-2 s-1 |
| Rn | Net radiation | W m-2 |
| SHF1 | Sensible heat flux, probe 1 | W m-2 |
| SHF2 | Sensible heat flux, probe2 | W m-2 |
| SHF3 | Sensible heat flux, probe 3 | W m-2 |
| SHF4 | Sensible heat flux, probe 4 | W m-2 |
| SHF5 | Sensible heat flux, probe 5 | W m-2 |
| SHFM | Sensible heat flux mean | W m-2 |
| ST002a | Soil temperature, 0.02 m depth, probe a | degrees Celsius |
| ST005a | Soil temperature, 0.05 m depth, probe a | degrees Celsius |
| ST010a | Soil temperature, 0.1 m depth, probe a | degrees Celsius |
| ST050a | Soil temperature, 0.5 m depth, probe a | degrees Celsius |
| ST100a | Soil temperature, 1 m depth, probe a | degrees Celsius |
| ST002b | Soil temperature, 0.02 m depth, probe b | degrees Celsius |
| ST005b | Soil temperature, 0.05 m depth, probe b | degrees Celsius |
| ST010b | Soil temperature, 0.1 m depth, probe b | degrees Celsius |
| ST050b | Soil temperature, 0.5 m depth, probe b | degrees Celsius |
| ST100b | Soil temperature, 1 m depth, probe b | degrees Celsius |
| ST002M | Soil temperature, 0.02 m depth, probe M | degrees Celsius |
| ST005M | Soil temperature, 0.05 m depth, probe M | degrees Celsius |
| ST010M | Soil temperature, 0.1 m depth, probe M | degrees Celsius |
| ST050M | Soil temperature, 0.5 m depth, probe M | degrees Celsius |
| ST100M | Soil temperature, 1 m depth, probe M | degrees Celsius |
| Tlog | Temperature, datalogger | degrees Celsius |
| Vref1 | Reference voltage1 | mV |
| Vref2 | Reference voltage2 | mV |
| SM010a | Soil moisture, 0.10 m, probe a | % |
| SM050a | Soil moisture, 0.50 m, probe a | % |
| SM100a | Soil moisture, 1 m, probe a | % |
| SM150a | Soil moisture, 1.5 m, probe a | % |
| SM010b | Soil moisture, 0.10 m, probe b | % |
| SM050b | Soil moisture, 0.50 m, probe b | % |
| SM100b | Soil moisture, 1 m, probe b | % |
| SM150b | Soil moisture, 1.5 m, probe b | % |
| SM010c | Soil moisture, 0.10 m, probe c | % |
| SM050c | Soil moisture, 0.50 m, probe c | % |
| SM100c | Soil moisture, 1 m, probe c | % |
| SM150c | Soil moisture, 1.5 m, probe c | % |
Additional information about the parameters measured, instrumentation, and data format is found in the companion file: http://daac.ornl.gov/daacdata/safari2k/climate_meteorology/maun_met_flux/comp/maun_met_flux_readme.pdf.
2004/9/22
2004/9/22
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