Abstract:

This dataset contains bathymetry soundings of Lagos Lagoon, Nigeria, collected in 2008 and 2014 for the purpose of examining short-term morphological changes in an area experiencing intense urbanization and industrial expansion. Also included are the along-track depth measurements along ten different tracks in the western half of the lagoon and estimations of the mean depth difference between re-occupations of the same track and spatial contrast within the same survey. This dataset supports the publication: Alfred Sunday Alademomi, Andrew J. Manning, Victor J. Abbott and Richard J.S. Whitehouse. (2020). Morphodynamics in a Tropical Shallow Lagoon: Observation and Inferences of Change. Lagoon Environments Around the World - A Scientific Perspective. IntechOpen. doi:10.5772/intechopen.90189.

Suggested Citation:

Manning, Andrew. 2021. Dataset for: Morphodynamics in a tropical shallow lagoon: observation and inferences of change. Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/n7-0sht-6s68

Publications:

Sunday Alademomi, A., J. Manning, A., J. Abbott, V., & J.S. Whitehouse, R. (2020). Morphodynamics in a Tropical Shallow Lagoon: Observation and Inferences of Change. Lagoon Environments Around the World - A Scientific Perspective [Working Title]. doi:10.5772/intechopen.90189

Purpose:

To understand the field sediment and bed data.

Data Parameters and Units:

Along-track distance [m], depth [m], depth difference between surveys [m], spatial and temporal contrast between track lines, significance [* = yes], depth difference [m], +/- limits [m].

Methods:

The data were collected aboard a 5.84 m survey vessel equipped with a 200 kHz SDE-285 single beam echo sounder (manufactured by SOUTH); the transducer was installed on a heave-compensated mount to de-couple the instrument from vessel heave. The data were processed using HYPACK software, referencing them to local chart datum for Nigeria (Lagos 1955 height). Because tidal height measurements were not made, predicted heights were used to de-tide the depth readings. Ten cross-lagoon profiles (A-J) were created at 100 m horizontal resolution within the western half of the lagoon. Please see figure 3 in the associated publication Alademomi et al. (2020). Coordinate System: The bathymetric sounding locations were recorded using geographical coordinates (latitude and Longitude) obtained from a hand-held GPS unit. geographical coordinates were then converted into the UTM (Universal Transverse Mercator) coordinate system: Eastings and Northings (i.e. X and Y, both in metres) grid using ArcGIS software. Z were the corresponding depths (also in metres). Bathymetry Data Reference Datum: The depth data (Z, in metres) acquired was referenced to Lagos 1955, the local chart datum used in Nigeria. Lagos 1955 is a vertical datum first defined in 1955 and is based on mean sea level at Lagos, 1912-1928 [https://epsg.org/datum_5194/Lagos-1955.html]. Please note that the file ‘Data - For Figure 12, 18 & 19.xls’ contains the 2008 survey measurements, while the file 'Data - For Figures 12, 18 & 19.xls’ contains the 2014 survey.

Instruments:

Single beam echo sounder (frequency—200 kHz, model—SDE-285 Single Frequency Digital Echo sounder, type—South.

Individual Files: