<abstract xmlns="http://www.w3.org/1999/xhtml">

Chlorophyll-<italic>a</italic> (Chl-<italic>a</italic>) concentration is an important issue in ocean ecosystem management and research. This study investigates seasonal and annual variability in Chl-<italic>a</italic> and its relationship with sea surface temperature (SST) and river discharge in the shelf region of the Northern Bay of Bengal (BoB), as well as validates satellite data against in-situ data. Moderate Resolution Imaging Spectroradiometer (MODIS) Aqua satellite data on Chl-<italic>a</italic> concentration and SST from 2002–2018 were used in this study. River discharge data were obtained from the Bangladesh Water Development Board (BWDB). The annual Chl-<italic>a</italic> concentration ranged from 2.08 to 2.94 mg m−3, with an average of 2.43 ± 0.24 mg m−3. The Chl-<italic>a</italic> concentration was found higher (2.21 ± 0.56 mg m−3) during the northeast monsoon (October–February) and lower (1.81 ± 1.14 mg m−3) during the pre-monsoon season (March–May). The study revealed a declining trend in Chl-<italic>a</italic> concentration from 2002 to 2018, and the rate of change was −0.0183 mg m−3 year−1. Chl-<italic>a</italic> concentration showed a weak inverse relationship with SST, both annually and seasonally, especially in the pre-monsoon season. River discharge masked the effect of SST on Chl-<italic>a</italic> variability during the southwest and northeast monsoon. A reasonable correlation (<italic>r</italic> = 0.78) was found between the MODIS-Aqua data and in-situ Chl-<italic>a</italic> observations.</abstract>

Chlorophyll-a (Chl-a) concentration is an important issue in ocean ecosystem management and research. This study investigates seasonal and annual variability in Chl-a and its relationship with sea surface temperature (SST) and river discharge in the shelf region of the Northern Bay of Bengal (BoB), as well as validates satellite data against in-situ data. Moderate Resolution Imaging Spectroradiometer (MODIS) Aqua satellite data on Chl-a concentration and SST from 2002–2018 were used in this study. River discharge data were obtained from the Bangladesh Water Development Board (BWDB). The annual Chl-a concentration ranged from 2.08 to 2.94 mg m−3, with an average of 2.43 ± 0.24 mg m−3. The Chl-a concentration was found higher (2.21 ± 0.56 mg m−3) during the northeast monsoon (October–February) and lower (1.81 ± 1.14 mg m−3) during the pre-monsoon season (March–May). The study revealed a declining trend in Chl-a concentration from 2002 to 2018, and the rate of change was −0.0183 mg m−3 year−1. Chl-a concentration showed a weak inverse relationship with SST, both annually and seasonally, especially in the pre-monsoon season. River discharge masked the effect of SST on Chl-a variability during the southwest and northeast monsoon. A reasonable correlation (r = 0.78) was found between the MODIS-Aqua data and in-situ Chl-a observations.

Seasonal and annual variability in chlorophyll-<italic>a</italic> in the shelf region of the Northern Bay of Bengal using MODIS-Aqua data

Oceanological and Hydrobiological Studies

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Seasonal and annual variability in chlorophyll- in the shelf region of the Northern Bay of Bengal using MODIS-Aqua data

Chlorophyll-a (Chl-a) concentration is an important issue in ocean ecosystem management and research. This study investigates seasonal and annual variability...

Time Series	a	b	r	R²	n
Southwest (June–September)	−5.505	0.254	0.224	0.050	61
Northeast (October–February)	0.345	0.070	0.283	0.080	80
Pre-monsoon (March–May)	6.604	−0.168	−0.186	0.035	47
Annual data (2002–2018)	8.951	−0.237	−0.326	0.160	17

Seasonal and annual variability in chlorophyll-a in the shelf region of the Northern Bay of Bengal using MODIS-Aqua data

Article Category: Research Article

Data publikacji: 26 lis 2020

Zakres stron: 398 - 407

Otrzymano: 07 sty 2020

Przyjęty: 24 kwi 2020

DOI: https://doi.org/10.1515/ohs-2020-0035

© 2020 Faculty of Oceanography and Geography, University of Gdańsk, Poland

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

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Statistical analysis of Chl-a concentration and SST