Assessment of variability in chlorophyll-a and covariates in East/Japan sea: New insights from the ARIMAX model and wavelet coherence

IF 1.8 4区地球科学 Q3 GEOCHEMISTRY & GEOPHYSICS

Journal of Atmospheric and Solar-Terrestrial Physics Pub Date : 2025-02-05 DOI:10.1016/j.jastp.2025.106450

Salman Tariq , Ayesha Mariam , Muhammad Khan

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引用次数: 0

Abstract

The atmospheric aerosols and the concentration of Chlorophyll-a (Chl-a) in coastal and clear water is an important research field that involves the multiple aspects of environmental degradation and analyzing the health of the marine environment. Therefore, ocean color satellite remote sensing is an efficient way to observe and monitor the aquatic system and the ocean at various spatial, temporal, and spectral scales. Therefore, this study analyzes the spatiotemporal dynamic variability in various ocean color variables, i.e., Sea surface temperature (SST), Aerosol optical depth (AOD), Black carbon dry deposition (BCD), Calcite concentration (CC), Ocean Rain (O-Rain), and Sensible heat flux (SHF) over the East/Japan Sea (EJS) from 2002 to 2023. Furthermore, we used the ARIMAX model and Wavelet coherence (WTC) analysis for analyzing the variability of these oceanic parameters with Chl-a. The spatial concentration of Chl-a is observed high over the northern EJS, particularly around 141ᵒ E, 50ᵒ N, southwestern EJS, and around 141ᵒ E, 43ᵒ N (along the Japanese coast). Furthermore, the western EJS also showed the highest concentration of Chl-a than the eastern EJS. Generally, the mean concentration of Chl-a in EJS increasing at the rate of 0.4 mg m⁻³/yr showed the maximum value of 0.8 mg m⁻³ during the study period. Moreover, the ARIMAX models elucidated a direct coupling of the Chl-a with O-Rain and BCD while it showed an inverse and statistically significant association with AOD, SST, CC, and SHF. The WTC analysis indicated a strong association of above 0.8 of Chl-a with all selected variables between a scale period of 8–16. Among all selected variables, CC, SHF, and BCD show a stronger association with Chl-a over the EJS. Therefore, this study will help the policymakers in identifying the major hotspots of Chl-a in EJS to analyze the water quality and health of the marine environment.

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来源期刊

Journal of Atmospheric and Solar-Terrestrial Physics 地学-地球化学与地球物理

CiteScore

4.10

自引率

5.30%

发文量

审稿时长

6 months

期刊介绍： The Journal of Atmospheric and Solar-Terrestrial Physics (JASTP) is an international journal concerned with the inter-disciplinary science of the Earth''s atmospheric and space environment, especially the highly varied and highly variable physical phenomena that occur in this natural laboratory and the processes that couple them. The journal covers the physical processes operating in the troposphere, stratosphere, mesosphere, thermosphere, ionosphere, magnetosphere, the Sun, interplanetary medium, and heliosphere. Phenomena occurring in other "spheres", solar influences on climate, and supporting laboratory measurements are also considered. The journal deals especially with the coupling between the different regions. Solar flares, coronal mass ejections, and other energetic events on the Sun create interesting and important perturbations in the near-Earth space environment. The physics of such "space weather" is central to the Journal of Atmospheric and Solar-Terrestrial Physics and the journal welcomes papers that lead in the direction of a predictive understanding of the coupled system. Regarding the upper atmosphere, the subjects of aeronomy, geomagnetism and geoelectricity, auroral phenomena, radio wave propagation, and plasma instabilities, are examples within the broad field of solar-terrestrial physics which emphasise the energy exchange between the solar wind, the magnetospheric and ionospheric plasmas, and the neutral gas. In the lower atmosphere, topics covered range from mesoscale to global scale dynamics, to atmospheric electricity, lightning and its effects, and to anthropogenic changes.