Browsing by Author "Appeaning, A.K."
Now showing 1 - 5 of 5
Results Per Page
Sort Options
Item Coastal Erosion Management in Ghana: Combining Local Knowledge with Empirical Research.(2016) Appeaning, A.I; Appeaning, A.K.Coastal erosion along the Accra coast has become a chronic phenomenon that threatens both life and property. The issue has assumed a center stage of national debate in recent times due to its impact on the coastal communities. Lack of reliable geospatial data hinders effective scientific investigations into the changing trends in the shoreline position. However, perception about coastal erosion by the local people and how far the shoreline has migrated inland over time is high in the coastal communities in Accra. This opens a new chapter in coastal erosion research approach to include local knowledge of the local settlers in developing sustainable coastal management. This paper adopted a scientific approach to estimate rate of erosion and tested the results against perceived erosion trend by the local settlers. The study used 1974 digital topographic map and 1996 aerial photograph. The end point rate statistical method in DSAS was used to compute the rates of change. The short term rate of change for the 22 years period under study was estimated as -0.91 ± 0.49 meters per annum. It was revealed that about 79 % of the shoreline is eroding while the remaining 21 % is either stabilized or accreting. It emerged from semi-structured interviews with inhabitants in the Accra coastal communities that an average of about 30 meters of coastal lands are perceived to have been lost to erosion for a period of about 20 years. This translates to historic rate of change of about 1.5 meters per year, which corroborate the results of the scientific study. Again this study has established that the local knowledge of the inhabitants about coastal erosion can serve as reliable information under scarcity of scientific data for coastal management analyses in developing countries.Item Coastal vulnerability and migration in Ghana(University of Ghana, 2015-04-17) Atiglo, D.Y.; Quashigah, J.; Neri, P.; Appeaning, A.K.; Codjoe, S.N.A.Coastal vulnerability to sea level rise and other hazards is expected to push migration due to loss of land, habitat and livelihood security. The migration literature on Ghana rarely links coastal environmental systems with migration. This study aimed (i) to assess the vulnerability of Ghana's coasts to inundation and erosion (ii) to explore the relation between coastal vulnerability and population change through migration. We used data from Ghana's 2000 and 2010 Population and Housing Censuses and remotely sensed data to develop a coastal vulnerability index (CVI) comprising physical and socioeconomic vulnerability. The physical vulnerability index (PVI) was based on coastal elevation, geomorphology, geology, local subsidence,. shoreline change, tidal range and wave height. The socioeconomic vulnerability index (SVI) was based on economic activity, socio-demographic characteristics and housing conditions. Due to unavailability of explicit out-migration data at the district level, we estimated net migration using the Census Survival Ratio method. The results of the PVI revealed that districts in the farthest western and eastern coasts are highly vulnerable. The SVI showed the eastern coastal districts as the most vulnerable. Consequently, three districts in the eastern coast of Ghana with the highest combined CVI also tend to have very high deficit migration. Simple linear regression models show a negative correlation between coastal vulnerability and net migration. The technique employed in this study provides an improved assessment of coastal vulnerability and contributes to evaluating the environment-migration nexusItem Modeling future flows of the Volta River system: Impacts of climate change and socio-economic changes(Elsevier B.V., 2018) Jin, L.; Whitehead, P.G.; Appeaning, A.K.; Amisigo, B.; Macadam, I.; Janes, T.; Crossman, J.; Nicholls, R.J.; McCartney, M.; Rodda, H.J.E.As the scientific consensus concerning global climate change has increased in recent decades, research on potential impacts of climate change on water resources has been given high importance. However in Sub-Saharan Africa, few studies have fully evaluated the potential implications of climate change to their water resource systems. The Volta River is one of the major rivers in Africa covering six riparian countries (mainly Ghana and Burkina Faso). It is a principal water source for approximately 24 million people in the region. The catchment is primarily agricultural providing food supplies to rural areas, demonstrating the classic water, food, energy nexus. In this study an Integrated Catchment Model (INCA) was applied to the whole Volta River system to simulate flow in the rivers and at the outlet of the artificial Lake Volta. High-resolution climate scenarios downscaled from three different Global Climate Models (CNRM-CM5, HadGEM2-ES and CanESM2), have been used to drive the INCA model and to assess changes in flow by 2050s and 2090s under the high climate forcing scenario RCP8.5. Results show that peak flows during the monsoon months could increase into the future. The duration of high flow could become longer compared to the recent condition. In addition, we considered three different socio-economic scenarios. As an example, under the combined impact from climate change from downscaling CNRM-CM5 and medium+ (high economic growth) socio-economic changes, the extreme high flows (Q5) of the Black Volta River are projected to increase 11% and 36% at 2050s and 2090s, respectively. Lake Volta outflow would increase +1% and +5% at 2050s and 2090s, respectively, under the same scenario. The effects of changing socio-economic conditions on flow are minor compared to the climate change impact. These results will provide valuable information assisting future water resource development and adaptive strategies in the Volta Basin. © 2018 Elsevier B.V.Item Monitoring sea level rise-induced hazards along the coast of Accra in Ghana(Natural Hazards, 2015-09) Appeaning, A.K.Sea level rise, increased erosion and flooding threaten vulnerable coastal communities globally. Monitoring the changes in the coastal zone enables the risk levels to be detected and quantified. Such information facilitates developing sustainable policies to effectively manage hazards in the coastal zone. This study used available geospatial data to assess the physical state of the Accra coast and established ground control points that will facilitate effective monitoring of change. The data used included a bathymetric map (hard copy) with last revision in 1992, digital topographic map (2002) of the coast, 2005 orthophoto map and the geology map of Accra. The reliability of the data was determined, and the data were analysed using GIS tool. Ten concrete ground control points were established, mapped using DGPS and connected to the Ghana national coordinate system to form a network for effective monitoring in the coastal zone. The results revealed that the western region of the Accra coast has lower elevations onshore which will facilitate inundation from sea level rise. Comparing nearshore bathymetric profiles indicates that the eastern coast is deeper relative to the central and western. This will enable waves to break closer to the coast under increasing sea level rise thereby dissipating energy to facilitate sediment transport. Computed potential sediment transport rate revealed that the rate ranges between 4.1 9 105 and 7.2 9 105 m3/year. Using the control points established as reference points to monitor the coastal system will enable changes that can result in hazard to be detected and quantified. Monitoring sea level rise-induced hazards along the coast of Accra in Ghana | Request PDF. Available from: https://www.researchgate.net/publication/275713921_Monitoring_sea_level_rise-induced_hazards_along_the_coast_of_Accra_in_Ghana [accessed Sep 11 2018].Item Quantitative Analysis of Shoreline Change Using Medium Resolution Satellite Imagery in Keta, Ghana(Marine Science, 2011) Appeaning, A.K.; Jayson-Quashigah, P.N.; Kufogbe, K.S.Shoreline change analysis provides important information upon which most coastal zone management and intervention policies rely. Such information is however mostly scarce for large and inaccessible shorelines largely due to expensive field work. This study investigated the reliability of medium resolution satellite imagery for mapping shoreline positions and for estimating historic rate of change. Both manual and semi-automatic shoreline extraction methods for multi-spectral satellite imageries were explored. Five shoreline positions were extracted for 1986, 1991, 2001, 2007 and 2011 covering a medium term of 25 years period. Rates of change statistics were calculated using the End Point Rate and Weighted Linear Regression methods. Approximately 283 transects were cast at simple right angles along the entire coast at 200m interval. Uncertainties were quantified for the shorelines ranging from ±4.1m to ±5.5m. The results show that the Keta shoreline is a highly dynamic feature with average rate of erosion estimated to be about 2m/year ±0.44m. Individual rates along some transect reach as high as 16m/year near the estuary and on the east of the Keta Sea Defence site. The study con-firms earlier rates of erosion calculated for the area and also reveal the influence of the Keta Sea Defence Project on erosion along the eastern coast of Ghana. The research shows that shoreline change can be estimated using medium resolution satellite imagery