The WASCAL Hydrometeorological Observatory in the Sudan Savanna of Burkina Faso and Ghana

Abstract

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 CO 2 . 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 CO 2 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. drologically enhanced version of the Weather and Research Forecasting Model.West Africa is a region for which high-quality hydrometeorological measurements are very scarce (Jones et al., 2015). However, such information is needed for a better scientific understanding of hydrological processes and their interactions with the atmosphere and the biosphere. Observational data form the basis for the development of reliable modeling approaches for climate change analyses, as well as for determining the impact of land cover changes in hydrology and other disciplines. Many regions in West Africa are characterized by significant land cover changes due to a widespread conversion of savanna and other ecosystems into agricultural land (Ouedraogo et al., 2009;Knauer et al., 2017), which is expected to continue in the future. Land cover change analysis is the basis for the development of sustainable land management practices that strengthen the resilience of socioecological systems against climate extremes and enhance food security. Moreover, substantial biosphere-precipitation feedbacks have been detected for the West African Core Ideas • A new hydrometeorological observatory was established for the Sudan Savanna. • More than 30 hydrometeorological variables in subhourly resolution are provided. • Water, energy, and CO 2 fluxes are monitored along a land use change gradient. • The data form the basis for...

Evapotranspiration in the Tono Reservoir Catchment in Upper East Region of Ghana Estimated by a Novel TSEB Approach from ASTER Imagery

“…In response to the drought conditions, a series of small earth dams and dugouts were constructed. It is within this scheme of dams and dugouts construction that the Tono irrigation dam with 93 million cubic meters storage capacity and a surface area of about 19.6 square kilometers was constructed [48][49][50][51][52]. We used field measured flux data from an eddy covariance system established at Kayoro Dakorenia (10.918100 N, −1.320900 W, 292 m a.s.l.)…”

“…Details of instrumentation and measurement campaigns implemented at the EC station are available at [48,52,53].…”

“…There is no ground-based thermal radiometer device to measure ground-based surface radiometric temperature to compare with the satellite-derived. However, the EC station of the study area is equipped with an open-path infrared gas analyzer (7500A, Li-COR) and a three-dimensional ultrasonic anemometer (CSAT3, Campbell) [48]. These devices measure atmospheric water vapor content, which is a major component in correcting for sonic temperature measured to actual temperature using [86] algorithms and implemented in the TK3 software.…”

Designing Transnational Hydroclimatological Observation Networks and Data Sharing Policies in West Africa

“…The pilot sites are used for real-life testing of newly developed climate services and as case studies. Other unique tools of micrometeorology research in this region are the three eddy-covariance stations (EC-stations) installed at locations with different land use practices allowing detailed analyses between land use and climate parameters Further technical specifications, data collection sensors, data type and use of these EC stations are provided by Bliefernicht et al (2013), Bliefernicht et al (2018) and Berger et al (2019). Each of the hydrological (e.g.…”

“…The infilling approach uses information from the neighboring sites and the nearby time steps (spatio-temporal infilling) for sub-daily measurements. More than twenty essential variables can be generated which are useful for land surface modelling (Bliefernicht et al 2018). Table 1 shows the current metadata of these AWOSs in each country.…”