Emmanuel Obuobie

• BSc MSc PhD (Natural Science)
• Senior Researcher at CSIR-Water Research Institute

Reference evapotranspiration (ETo) defines the maximum evapotranspiration that can occur in a basin. Its accurate estimation is therefore very important in accurately estimating how much water is available in any Basin for use since the actual Evapotranspiration (AET) that occurs depends on the ETo estimated. AET is a parameter that is difficult to...

Knowledge of recharge is essential for efficient and sustainable management of groundwater resources. The application of different groundwater recharge estimation methods, especially those that are based on independent parameters and/or datasets enhances confidence in the process. In this study, the Chloride Mass Balance (CMB), Water Table Fluctuat...

Understanding the evolving patterns of climate extremes is crucial for planning climate change adaptation and safeguarding vulnerable communities in the Lower Volta Basin, Ghana. This study utilised precipitation, temperature and relative humidity data from CHIRPS and ERA5, as well as 13 CORDEX-Africa model projections for RCP4.5 and RCP8.5, to eva...

Thirteen satellite precipitation products (SPPs), re-gridded to 1 km resolution, were evaluated in terms of the structural similarity index (SSI) over the Pra catchment in Ghana. Three SPP scenarios were considered: Scenario one (S1) was the original SPPs; Scenario two (S2) was bias-corrected SPPs; and Scenario three (S3) was the better of S1 and S...

Although Ghana is a leading global cocoa producer, its production and yield have experienced declines in recent years due to various factors, including long-term climate change such as increasing temperatures and changing rainfall patterns, as well as drought events. With the increasing exposure of cocoa-producing regions to extreme weather events,...

The increasing impacts of climate change instigate the need for adaptation. However, most adaptation initiatives focus on actions by government or businesses, despite growing calls for communities on the frontline of climate risks to be involved in planning and selecting strategies. Here we appraise a pilot process using participatory systems mappi...

The study employed pairwise statistics (BIAS, R and NSE) to assess the potential of five different satellite rainfall products (CHIRPS, PERSIANN, TRMM, RFE, and ARC) in reproducing the hydrology of the Black Volta Basin. This was achieved by using the HEC-HMS model calibrated with observed streamflow data from three gauged stations (Lawra, Chache a...

Renewable energy system development and improved operation can mitigate climate change. In many regions, hydropower is called to counterbalance the temporal variability of intermittent renewables like solar and wind. However, using hydropower to integrate these renewables can affect aquatic ecosystems and increase cross-sectoral water conflicts. We...

Comparative study of approaches debugs the uncertainty associated with recharge estimates and improves confidence in decision making toward groundwater allocation. In this study, Soil and Water Assessment Tool (SWAT) was used to develop water balance to estimate groundwater recharge of the Vea catchment with 36-year (1983–2018) climate data from 11...

Hydropower is a renewable source of electricity generation that is a common feature of Nationally Determined Contributions (NDC), especially in developing countries. However, far from benign, research shows that significant greenhouse gas (GHG) emissions emanate from shallow reservoirs when they are sited in the tropics. Ghana provides a case study...

Study region Volta River Basin, West Africa Study focus Hydrological droughts have a wide range of impacts on societies and economic sectors such as agriculture and energy production. Analysis of hydrological droughts helps better plan and manage water resources under global change. This study analyses the spatial and temporal variability of hydro...

Jointly managing water and energy systems, rather than treating each system independently, is recognised as an approach that can lead to a more cost-effective and reliable supply, which is particularly critical in water-rich and developing countries. This has motivated the development of various integrated water-energy simulators, each one catering...

Large energy infrastructure can imply special financing arrangements between governments in developing economies and investors or lenders. These arrangements can lead to economy-wide and sector-specific impacts which need to be considered in the project economic evaluation. By considering the case of the Bui Dam in Ghana, we use a macroeconomic app...

Study region Densu River Basin in Ghana, West Africa. Study focus This paper reviews aquifers and groundwater resources in the Densu River Basin based on several past studies which adopted hydrochemical, numerical modelling, geostatistical techniques, and several other conventional methods with particular focus on the hydrogeological and hydrochem...

Accurate estimation of evapotranspiration (ET) is required for a good estimation of available water for use in any catchment as ET constitutes major means by which water is lost in any catchment. SWAT model uses climate data in estimating potential evapotranspiration (PET). The PET together with other parameters is then used in estimating actual ev...

Statistical imputation techniques for infilling missing records in daily rainfall data within the Pra and the Densu River basins in Ghana were evaluated. The imputation techniques considered were Mean, Regression, Multiple Imputation by Chain Equation, K Nearest Neighbor, Probabilistic Principal Component Analysis, missForest, Linear Interpolation,...

Conventional satellite sensors provide periodic data for monitoring Artisanal and Small-Scale Mining (ASM). Incorporating Unmanned Aerial Vehicle (UAV) sensors in monitoring ASM can increase data availability and also mitigate the challenge of cloud cover that causes data gaps in satellite data availability. However, most UAV sensors measure only i...

Access to water is a matter of daily survival for people around the world. Water is crucial for human survival and also central to the development of every nation. The recent literature on world water suggests that the water crisis being experienced is related to governance and not a real crisis of scarcity and stress. This paper aims at identifyin...

New dams impact downstream ecosystems and water infrastructure; without cooperative and adaptive management, negative impacts can manifest. In large complex transboundary river basins without well codified operating rules and extensive historical data, it can be difficult to assess the benefits of cooperating, in particular in relation to new dams....

This study evaluated the performance of five satellite rainfall products (CHIRPS, PERSIANN, TRMM, RFE, and ARC) in the Black Volta Basin (BVB) using four performance evaluation methods: pairwise statistics, categorical statistics, rainfall intensity distribution, and extreme rainfall indices. In all, 21 rainfall stations distributed across the BVB...

The need for a detailed investigation of the Vea catchment water balance components cannot be overemphasized due to its accelerated land cover dynamics and the associated impacts on the hydrological processes. This study assessed the possible consequences of land-use change scenarios (i.e. business as usual, BAU, and afforestation for the year 2025...

The design of water and energy systems has traditionally been done independently or considering simplified interdependencies between the two systems. This potentially misses valuable synergies between them and does not consider in detail the distribution of benefits between different sectors or regions. This paper presents a framework to couple int...

This study used the RClimDex software to examine trends in extreme air temperature and rainfall in the Black Volta River Basin (BVRB) for the present (1981–2010) and future 2051–2080 (late twenty-first century) horizons. The analysis of the future extreme events was conducted using data output of four ensemble models for two IPCC emission scenarios...

The extent to which statistical bias-adjusted outputs of two regional climate models alter the projected change signals for the mean (and extreme) rainfall and temperature over the Volta Basin is evaluated. The outputs from two regional climate models in the Coordinated Regional Climate Downscaling Experiment for Africa (CORDEX-Africa) are bias adj...

IWMI Working Paper – 179 Citation: Mul, M.; Pettinotti, L.; Amonoo, N. A.; Bekoe-Obeng, E.; Obuobie, E. 2017. Dependence of riparian communities on ecosystem services in northern Ghana. Colombo, Sri Lanka: International Water Management Institute (IWMI). 43p. (IWMI Working Paper 179). [doi: 10.5337/2018.201] Download PDF 1.44 MB Abstract This...

The impacts of dam releases from re-operation scenarios of the Akosombo and Kpong hydropower facilities on downstream communities along the Lower Volta River were examined through hydrodynamic modelling using the HEC-RAS hydraulic model. The model was used to simulate surface water elevation along the river reach for specified discharge hydrographs...

This paper provides the climatic and biophysical context of three watersheds in northern Ghana - Anyari and Zanlerigu in the Upper East region and Bihinaayili in the Northern region. The objective of the study is to describe the agro-climatic and hydrological features of the watersheds from a landscape perspective, which can be used as baseline inf...

The study analyzed the trends in observed (1981-2010) and future projected annual precipitation and mean temperature over the Black Volta River Basin using the Mann-Kendall test and the Sen’s slope estimator. Projected changes in precipitation and temperature by multi-model ensemble runs over the Black Volta basin for the late (2051-2075) and end o...

The Vea catchment, mainly underlain by crystalline basement rocks, is located in Northern Ghana. Hydrogeochemical studies were carried out in this area with the objective of identifying the geochemical processes influencing water quality and suitability of surface and groundwater for agricultural and domestic uses. Sixty-one groundwater and four su...

Development times of eggs, larvae and pupae of vectors of onchocerciasis (Simulium spp.) and of Onchocerca volvulus larvae within the adult females of the vectors decrease with increasing temperature. At and above 25°C, the parasite could reach its infective stage in less than 7 days when vectors could transmit after only two gonotrophic cycles. Af...

The Volta Basin is a transboundary basin shared by six riparian countries. In 2007, the Volta Basin Authority (VBA) was established and it was mandated to provide legal and institutional arrangements among the riparian countries for managing the water resources of the Volta Basin. The transboundary diagnostic analysis commissioned by the VBA has hi...

This paper assesses the groundwater resource potential for dry-season vegetable irrigation in two areas of north-eastern Ghana. It uses multiple methods, including geophysical surveying, recharge estimation, and water quality analysis. Results indicate that groundwater abstractions for all purposes are small compared to recharge. The quality of gro...

This study uses the Soil and Water Assessment Tool (SWAT) and downscaled climate projections from the ensemble of two global climate models (ECHAM4 and CSIRO) forced by the A1FI greenhouse-gas scenario to estimate the impact of climate change on streamflow in the White Volta and Pra river basins, Ghana. The SWAT model was calibrated for the two bas...

Groundwater development potential in northern Ghana (108 671 km2) has been assessed by combining spatial layers for five critical factors—recharge rate, regolith thickness, transmissivity, borehole success rate and static water level—through a multi-criteria analysis approach to rank development potential from the viewpoint of groundwater availabil...

The Falkenmark indicator was used to assess vulnerability of the White Volta (106,000 km2) and Pra (20,023 km2) river basins in Ghana to water stress under climate change for the periods 2006-2035 (representing the 2020s) and 2036-2065 (2050s). The indicator is a commonly used measure of water stress and defines thresholds of 1,700, 1,000 and 500 m...

Coping strategies including smoke screens are used against nuisance bites of Simulium damnosum Theobald (Diptera:Simuliidae) in onchocerciasis endemic communities. To find more effective alternatives, the efficacy of commercially available N,N-diethyl-3-methylbenzamide (DEET) products with active concentrations of 9.5, 13, 25, 50 and 98.1-100% and...

Recharge quantification is an important pre-requisite for effectively managing groundwater resources as recharge estimates are needed to determine sustainable yields of groundwater aquifers for rational and sustainable exploitation of the resource. In this study, the water table fluctuation method has been applied in the White Volta River basin of...

This study uses the chloride mass balance (CMB) method to estimate the recharge to the groundwater aquifers in the upper east region (UER) in northeastern Ghana. In addition, the recharge is compared with water demand to understand the potential of groundwater for improving water supply. The UER is one of the most densely populated areas in Ghana a...

International Water Management Institute West Africa sub-regional Office, Accra Ghana This paper describes the roles and values of male and female with respect to production, and marketing of vegetable crops within Accra, Ghana. An attempt has been made to (1) explore and compare labor divisions and responsibility among members in farming and non-f...

The Soil and Water Assessment Tool (SWAT) model was applied in the White Volta river basin, West Africa, to simulate the streamflow and to estimate the impact of future climate change on the streamflow. The White Volta river basin is one of the three major sub-basins of the Volta river basin, and drains an area of about 106,000 km2 mainly shared by...