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Watersheds with rich hydrometeorological equipment are still very limited in West Africa but are essential for an improved analysis of environmental changes and their impacts in this region. This study gives an overview of a novel hydrometeorological observatory that was established for two mesoscale watersheds in the Sudan Savanna of Southern Burkina Faso and Northern Ghana as part of the West African Science Service Centre on Climate Change and Adapted Land Use (WASCAL) program. The study area is characterized by severe land cover changes due to a strongly increasing demand of agricultural land. The observatory is designed for long-term measurements of >30 hydrometeorological variables in subhourly resolution and further variables such as CO2. This information is complemented by long-term daily measurements from national meteorological and hydrological networks, among several other datasets recently established for this region. A unique component of the observatory is a micrometeorological field experiment using eddy covariance stations implemented at three contrasting sites (near-natural, cropland, and degraded grassland) to assess the impact of land cover changes on water, energy, and CO2 fluxes. The datasets of the observatory are needed by many modeling and field studies conducted in this region and are made available via the WASCAL database. Moreover, the observatory forms an excellent platform for future investigations and can be used as observational foundation for environmental observatories for an improved assessment of environmental changes and their socioeconomic impacts for the savanna regions of West Africa.

Aims Direct and indirect costs of ischaemic heart disease were assessed in Switzerland, for the period 1988-1993, in order to evaluate the economic consequences of more intensive treatment of the disease and of the decreasing mortality from ischaemic heart disease in the working population. Methods and Results A societal perspective was taken for a prevalence-based assessment of the direct (total resources consumed by outpatients and inpatients) and indirect (due to morbidity, invalidity, and premature death, using the human capital approach) costs. The results showed the total costs were 21 million US dollars per 100 000 population in the year 1993 (47% direct, 53% indirect costs). The largest components were the direct costs of inpatient care and indirect costs due to premature death (each approximately 25% of the total). Trends showed a large increase in direct costs (+9% per year, constant dollars). Indirect costs stabilized or decreased slightly due to the reduction of work losses. Conclusions Today's medicine and preventive measures have proven effective for ischaemic heart disease, although such remedies have required increasingly large financial resources. However, society benefits because indirect costs decrease, although this gain does not compensate for all direct costs

The characterization and evaluation of the recent status of biodiversity in Southern Africa’s Savannas is a major prerequisite for suitable and sustainable land management and conservation purposes. This paper presents an integrated concept for vegetation type mapping in a dry savanna ecosystem based on local scale in-situ botanical survey data with high resolution (Landsat) and coarse resolution (MODIS) satellite time series. In this context, a semi-automated training database generation procedure using object-oriented image segmentation techniques is introduced. A tree-based Random Forest classifier was used for mapping vegetation type associations in the Kalahari of NE Namibia based on inter-annual intensity- and phenology-related time series metrics. The utilization of long-term inter-annual temporal metrics delivered the best classification accuracies (Kappa = 0.93) compared with classifications based on seasonal feature sets. The relationship between annual classification accuracies and bi-annual precipitation sums was conducted using data from the Tropical Rainfall Measuring Mission (TRMM). Increased error rates occurred in years with high rainfall rates compared to dry rainy seasons. The variable importance was analyzed and showed high-rank positions for features of the Enhanced Vegetation Index (EVI) and the blue and middle infrared bands, indicating that soil reflectance was crucial information for an accurate spectral discrimination of Kalahari vegetation types. Time series features related to reflectance intensity obtained increased rank-positions compared to phenology-related metrics.

Through its excellent radiometric and geometric calibration and the direct broadcast capability, the Moderate Resolution Imaging Spectroradiometer (MODIS) on-board the Terra and Aqua platforms is an ideal data source for near-real time applications. DLI (Department of Land Information WA) - Satellite Remote Sensing Services is processing MODIS data received in Alice Springs, Hobart and Perth covering Australia, New Zealand and parts of south-east Asia. It has developed an automatic near-real time processing system for applications such as fire monitoring, flood mapping and vegetation monitoring. The system is built in a modular design. It consists of modules for active fire detection, top-of-atmosphere vegetation index generation, atmospheric parameter retrieval and atmospheric correction. The atmospherically corrected data gets fed into additional modules for flood mapping, BRDF retrieval, high resolution fire detection and burnt area mapping. Satellite Remote Sensing Services is disseminating the products generated to users via a range of web and internet services as well as a fax service. This paper provides an overview over the processing system as well as explains some modules in more detail. It discusses the implications of availability of auxiliary data necessary for the processing. The time delays between data acquisition and product availability are shown together with some application examples. Another focus is put on the temporal coverage for different regions.