Date of Award

4-2016

Document Type

Thesis

Degree Name

Master of Science (MS)

Department

Environmental Science

First Advisor

Abdelgadir Abuelgasim

Second Advisor

Khalid Hussein

Third Advisor

Rami AI-Ruzoug

Abstract

The Arabian Gulf is a semi enclosed large water body that experiences seasonal

variations and reversal of it water currents flow circulation. The Gulf waters are characterized by having high primary productivity and strong phytoplankton blooms at particular seasons within the year. Phytoplankton is a base of the food chain for marine species, providing an essential food resource for aquatic life. Marine phytoplankton affects the diversity of any marine ecosystem and drives its functioning and is strongly correlated with fishery yields. The primary

objectives of this research study are to answer key research questions related to phytoplankton blooms in the Arabian Gulf. The research attempts to identify the seasonal and inter- annual variations of phytoplankton blooms, the factors that affects these blooms, and the spatial distribution of such blooms within the Gulf waters using the Moderate Resolution Imaging Spectroradiometer – AQUA (MODISA) and the Advanced Scatter meter (ASCAT) satellite data. MODIS

derived chlorophyll concentration (chlorophyll-a) product (as indicator of phytoplankton) and MODIS sea surface temperature product (SST) over the study area are utilized. ASCAT wind vectors are used to identify the prevailing wind direction over the study area. The major findings from this research are that observed phytoplankton concentrations in the Arabian Gulf experience wide

Variability from season to season each year. The onset of phytoplankton blooms in the Arabian Gulf starts in early autumn season reaching its peak at the end of the season and into the onset of the winter season. High levels of phytoplankton concentrations remain visible in the satellite data through the winter season where it starts to disappear towards the end of the season. The spring and summer seasons portray the lowest levels of phytoplankton with no apparent Bloom during the study period in these seasons. The percentile increase between the minimum and maximum concentrations is almost 140%. The phytoplankton blooms in the Arabian Gulf are strongly influenced by the sea surface temperature, the prevailing winds, and their directions. Phytoplankton blooms are associated with the northeasterly wind regime of autumn and winter

Coupled by lower SST. A strong positive inverse relation between chlorophyll concentrations and sea surface temperature within the study area are observed from the satellite data. During the study period 2003-2013 a decline in the overall chlorophyll concentrations of approximately 2% - 4% is observed. This is currently assessed from only 9 to 11 observations spanning the years of the study period. This is not a statistically valid

Sample to make a major conclusions vis-à-vis the trend of the phytoplankton concentrations in the Arabian Gulf. To have a statistically valid sample, a minimum of 30 observations are needed from MODIS observations. However, the results are in agreement with previous studies of declining phytoplankton concentrations globally. The summary of the results of this study provided key

Information in regards to the study’s major research questions

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