Browsing by Author "Nyadjro, E.S."
Now showing 1 - 3 of 3
Results Per Page
Sort Options
Item Enhancing Satellite Oceanography-Driven Research in West Africa: a Case Study of Capacity Development in an Underserved Region(Remote Sensing in Earth Systems Sciences, 2021) Nyadjro, E.S.; Mahu, E.; Addo, K.A.; et al.Marine business and resources play a major role in the economics and way of life in coastal West African countries. Such countries see great profitability from their marine resources while also facing challenges that come with a bordering sea. Despite Due to this fact, there has been limited research into the optimal way for West African Coastal States to coexist with and sustainably use their marine resources, a research deficit that is mainly due to a lack of infrastructure for in-situ work, lack of capacity development, and comprehensive datasets to undertake oceanographic research. The Coastal Ocean Environment Summer School in Ghana (COESSING; www.coessing.org) was developed to help meet some of these challenges. Each summer since 2015, ocean scientists (e.g., biologists, chemists, physicists, hydrologists) from the USA and Europe have collaborated with West African colleagues to lead a week-long intensive summer school in Accra, Ghana, alternating in location between the Regional Maritime University and the University of Ghana. The school receives in excess of 100 participants drawn from universities, government agencies, and private sector organizations, mainly from Ghana and neighboring Liberia, Nigeria, Togo, and Benin, among others. The format of the school includes morning lectures, afternoon field trips, hands-on laboratory exercises and one-on-one coaching of students. Important to the COESSING program is the satellite oceanography component, which introduces participants to the extensive and often free, remotely sensed oceanographic datasets. Participants develop skills that allow them to access, process, and analyze these datasets in order to better understand regional oceanographic phenomena, such as upwelling, pollution, habitat characterization, sea level rise, and coastal erosion. Following school, facilitators keep in touch with program participants, helping them acquire and analyze data for their studies, dissertations, and often graduate school applications, etc. In summary, schools such as COESSING are critical not only for science in the region but for the global ocean community as such training develops eager, bright minds while leading to improved regional observation and modeling strategies in severely under-sampled seas. Here, we describe a unique case in which satellite oceanography has led to such outcomes for countries bordering the Gulf of Guinea, West AfricaItem Satellite observations of upwelling in the gulf of Guinea(IEEE Geoscience and Remote Sensing Letters, 2015-05) Wiafe, G.; Nyadjro, E.S.The classical case of favorable winds driving coastal upwelling does not adequately account for the upwelling observed along the northwestern Gulf of Guinea (GoG) coast, which is the area of focus in this letter. Herein, we used mainly satellite-derived data to examine the dynamics of upwelling in the study area. Upwelling indexes are derived from sea surface temperature (SST) and wind influences. Low SST, which is a characteristic of upwelling, is observed mainly along the entire coastal region from July to September. The relative contributions of local wind forcing are quantified; the wind-stress-driven Ekman transport was more important than the wind-stress-curl-driven Ekman pumping in affecting changes in SST. They both however do not entirely explain the upwelling that is observed along the entire coast. It is shown that winds in the western equatorial Atlantic force eastward propagating upwelling Kelvin waves that lead to lowering of sea level and SST along the northwestern GoG coast. � 2014 IEEE.Item Seasonal Variability of Sea Surface Salinity in the NW Gulf of Guinea from SMAP Satellite(Remote Sensing in Earth Systems Sciences, 2022) Nyadjro, E.S.; Foli, B.A.K.; Agyekum, K.A.; et al.The advent of satellite-derived sea surface salinity (SSS) measurements has boosted scientific study in less-sampled ocean regions such as the northwestern Gulf of Guinea (NWGoG). In this study, we examine the seasonal variability of SSS in the NWGoG from the Soil Moisture Active Passive (SMAP) satellite and show that it is well-suited for such regional studies as it is able to reproduce the observed SSS features in the study region. SMAP SSS bias, relative to in-situ data comparisons reflects the differences between skin layer measurements and bulk-surface measurements that have been reported by previous studies. The study results reveal three broad anomalous SSS features: a basin-wide salinification during boreal summer, a basin-wide freshening during winter and a meridionally-oriented frontal system during other seasons. A salt budget estimation suggests that seasonal SSS variability is dominated by changes in freshwater flux, zonal circulation and upwelling. Freshwater flux, primarily driven by the seasonally varying Intertropical Convergence Zone is a dominant contributor to salt budget in all seasons except during fall. Regionally, SSS is most variable off southwestern Nigeria and controlled primarily by westward extensions of the Niger River. Anomalous salty SSS off the coasts of Cote d’Ivoire and Ghana, especially during the summer, is driven mainly by coastal upwelling and horizontal advection.