Remote sensing of chlorophyll-a concentrations in coastal oceans of the Greater Bay Area in China: Algorithm development and long-term changes

Tong，Yan; Feng，Lian; Zhao，Dan; Xu，Wang; Zheng，Chunmiao

2022-08-01

10.1016/j.jag.2022.102922

International Journal of Applied Earth Observation and Geoinformation   Impact Factor & Quartile

1569-8432

1872-826X

Extensive human activities and climate change in recent decades have triggered severe eutrophication problems in the coastal oceans in the Greater Bay Area (GBA) of China. However, a comprehensive characterization of the spatial and temporal patterns of chlorophyll-a (Chl-a, a major indicator of phytoplankton biomass) in this region is not available. Our study attempts to fill this gap by using long-term satellite observations. With massive in situ datasets from underway sampling systems, we developed a novel hybrid Chl-a retrieval algorithm combining the recalibrated OC3 and line-height-based (BL443) algorithms for waters with different turbidity levels. Satellite-retrieved Chl-a values with the hybrid algorithm agreed well with in situ measurements, with an uncertainty level of 33.8 %. Long-term analysis revealed significant decreasing trends over the inner Pearl River Estuary (averaged at 0.054 μg/L yr), while significant increasing trends were found in eastern Daya Bay (averaged at 0.035 μg/L yr). The developed algorithm is expected to aid routine Chl-a monitoring in the adjacent oceans of the GBA, and the long-term datasets here can serve as critical information for further coastal conservation and management efforts.

Chlorophyll-a Coastal Ocean Greater Bay Area Hybrid Algorithm OC3

SCI

English

First ; Corresponding

National Natural Science Foundation of China["41890851","41890852","41971304"] ; Shenzhen Science and Technology Innovation Committee[JCYJ20190809155205559]

Remote Sensing

Remote Sensing

WOS:000844311400003

ELSEVIER

2-s2.0-85135390942

Scopus

School of Environmental Science and Engineering,Southern University of Science and Technology,Shenzhen,China

Tong，Yan,Feng，Lian,Zhao，Dan,et al. Remote sensing of chlorophyll-a concentrations in coastal oceans of the Greater Bay Area in China: Algorithm development and long-term changes[J]. International Journal of Applied Earth Observation and Geoinformation,2022,112.

Tong，Yan,Feng，Lian,Zhao，Dan,Xu，Wang,&Zheng，Chunmiao.(2022).Remote sensing of chlorophyll-a concentrations in coastal oceans of the Greater Bay Area in China: Algorithm development and long-term changes.International Journal of Applied Earth Observation and Geoinformation,112.

Tong，Yan,et al."Remote sensing of chlorophyll-a concentrations in coastal oceans of the Greater Bay Area in China: Algorithm development and long-term changes".International Journal of Applied Earth Observation and Geoinformation 112(2022).