Conference Proceedings and Papers

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Conference proceeding is a collection of academic papers published in the context of an academic conference or workshop. Conference proceedings typically contain the contributions made by researchers at the conference. They are the written record of the work that is presented to fellow researchers.

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Browsing Conference Proceedings and Papers by Author "Agyekum, K.A."

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    Observations of thermal variations in the mixed layer depth of the equatorial Atlantic
    (International Geoscience and Remote Sensing Symposium (IGARSS), 2009-01) Agyekum, K.A.; Wiafe, G.; Houghton, B.; Dolk, S.; Drake, T.; Vogel, A.
    A set of Argo temperature data collected in the equatorial Atlantic [0° -5° N, 55° W-10° E] was used to estimate the mixed layer depth (MLD) and associated thermal variability for the period between January 2002 to April 2009. MLD climatology were estimated from 0.3° *0.3° median binned temperature profile using temperature difference criterion with a reference layer at 10m depth. At the 30m depth, 22° C cold water flows from the south onto the continental shelfs of Ghana-Cote D'Ivoire indicating the potential source of nutrient rich bottom water that nourishes the MLD and drives biological production. The MLD was shallow at the east and relatively deeper at the western end of the equatorial Atlantic. Variability within the MLD can be associated with variations in the westward flow of the warm and saline Equatorial Undercurrent. Further warming of the equatorial Atlantic has a potential of increasing the mixed layer depth and affecting upper surface ocean processes. ©2009 IEEE.
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    Use of Sentinel-l and Sentinel-2 for Monitoring Illegal Fishing Off Ghana
    (International Geoscience and Remote Sensing Symposium (IGARSS), 2018-07) Kurekin, A.; Loveday, B.; Clements, O.; Quartly, G.; Miller, P.; Wiafe, G.; Agyekum, K.A.
    An efficient and inexpensive service has been developed for the monitoring of fishing vessels in West Africa using Earth Observation (EO) data. The service makes use of fast- delivery data from the Synthetic Aperture Radar (SAR) instrument on Sentinel-1 and the Multi Spectral Imager (MSI) on Sentinel-2, detecting objects that differ markedly from their immediate background using a constant false alarm rate (CFAR) test. The selected objects are then discounted from further analysis if they fall within the bespoke land mask or can be shown from time series analysis to be static (signals associated with jetties, oil platforms and "ghost objects" arising from very bright land targets). Detections are matched to, and verified by, AIS data, which provides location and dimensions of ships that are legally in the region. Both matched and un-matched data are then displayed on a web portal for use by the Gulf of Guinea (GoG) state authorities.