Spatiotemporal variability of global ocean Chlorophyll-a concentration and its correlation with climate change factors
WENG Qingpeng
QIN Quan
LI Feng
FENG Donghan
HAN Dongfeng
WANG Han
LU Chen
LIU Juncheng
Abstract：Chlorophyll-a(Chl-a)concentration serves as a crucial indicator of marine phytoplankton biomass,reflecting the richness and diversity of marine ecosystems.Satellite remote sensing technology offers significant advantages in monitoring the spatiotemporal distribution of large-scale Chl-a concentrations across global ocean waters.Using MODIS(Moderate Resolution Imaging Spectroradiometer)Chl-a concentration data from 2003 to 2022,this study analyzes the spatiotemporal variability and trends of the Chl-a concentrations in global oceans,and their relationships with the global sea surface temperature(SST),El Niño-Southern Oscillation(ENSO)and the Indian Ocean Dipole(IOD)are examined.The results are outlined below.(1)Spatially,the Chl-a concentrations in coastal waters are generally higher than those in offshore waters,with the lowest concentrations observed in pelagic waters(less than 0.03 mg·m-3).Seasonally,Chl-a concentrations exhibit significant variations,with nearshore waters showing more pronounced seasonal changes than pelagic waters.(2)In the open waters of the Pacific,Indian and Atlantic oceans,the trend of the Chl-a concentrations remains mildly changes.However,Chl-a concentrations show an increasing trend in the majority of nearshore waters.(3)The months with the highest Chl-a concentrations across global ocean waters vary in a band-like pattern with latitude.(4)Generally,the Chl-a concentrations exhibit significant negative correlations with SST(p＜0.05)between 40 °S and 40° N,while positive correlations are observed in other latitudes.The correlations between Chl-a concentrations and ENSO/IOD also display significant seasonal variations,indicating that ENSO and IOD have different impacts on the variations of Chl-a concentrations in different sea regions.
Keywords：global oceanChl-a concentrationMODISENSOspatiotemporal variability
Publication Date：2025-04-30
Online Publishing Date：2026-05-22(First online date of this platform, not the publication date of the document)
Pages：9( 118-126 )