Upwelling on the Southeast Madagascan shelf: frequency, extent, and driving mechanisms
- Authors: Collins, Matthew
- Date: 2020
- Subjects: Upwelling (Oceanography) -- Madagascar , Oceanography -- Research -- Madagascar Marine biology -- Indian Ocean
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/49060 , vital:41597
- Description: The southeast coast of Madagascar, namely the region surrounding the town of Fort Dauphin, is an area that regularly experiences upwelling events. Two unique high frequency data sets, UTR data, and wind data retrieved from a nearby airport, are the primary data sets used to investigate the nature of the upwelling, i.e. the area that experiences upwelling, how often it occurs, and its mechanisms. To complement the in-situ data, several different satellite data sources are used alongside the in-situ data to study this relatively remote region, i.e. SST, chlorophyll-a concentration, current, and wind data. The results refine upon previous literature on the topic. The upwelling covers an area of 1o latitude by 1.3o longitude, and occurs on average 14 times per annum. The mechanism driving the upwelling can be attributed to both wind and current, with wind the more dominant driver along the south coast, and current more dominant along the east coast. Separate to the main objective of the thesis is the importance of in-situ data when analysing small scale events such as upwelling events. While the in-situ wind data were found to be unreliable due to its location within a valley, the UTR data were of vital importance in identifying and studying the finer details of the upwelling events. The satellite SST data, by comparison, were lacking in their ability to investigate the upwelling events. The satellite derived wind data, however, did prove useful when analysing the wind as a driver of the upwelling.
- Full Text:
- Date Issued: 2020
- Authors: Collins, Matthew
- Date: 2020
- Subjects: Upwelling (Oceanography) -- Madagascar , Oceanography -- Research -- Madagascar Marine biology -- Indian Ocean
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/49060 , vital:41597
- Description: The southeast coast of Madagascar, namely the region surrounding the town of Fort Dauphin, is an area that regularly experiences upwelling events. Two unique high frequency data sets, UTR data, and wind data retrieved from a nearby airport, are the primary data sets used to investigate the nature of the upwelling, i.e. the area that experiences upwelling, how often it occurs, and its mechanisms. To complement the in-situ data, several different satellite data sources are used alongside the in-situ data to study this relatively remote region, i.e. SST, chlorophyll-a concentration, current, and wind data. The results refine upon previous literature on the topic. The upwelling covers an area of 1o latitude by 1.3o longitude, and occurs on average 14 times per annum. The mechanism driving the upwelling can be attributed to both wind and current, with wind the more dominant driver along the south coast, and current more dominant along the east coast. Separate to the main objective of the thesis is the importance of in-situ data when analysing small scale events such as upwelling events. While the in-situ wind data were found to be unreliable due to its location within a valley, the UTR data were of vital importance in identifying and studying the finer details of the upwelling events. The satellite SST data, by comparison, were lacking in their ability to investigate the upwelling events. The satellite derived wind data, however, did prove useful when analysing the wind as a driver of the upwelling.
- Full Text:
- Date Issued: 2020