Chlorophyll-a (chl-a) is an important parameter of water quality and its concentration can be directly retrieved from satellite observations. The Ocean Land Color Instrument (OLCI), a new-generation water-color sensor onboard Sentinel-3A Sentinel-3B, excellent tool for marine environmental monitoring. In this study, we introduce new machine learning model, Light Gradient Boosting Machine (LightGBM), estimating time-series chl-a in Fujian’s coastal waters using multitemporal OLCI data situ...

Retrieving multi-temporal and large-scale thermohaline structure information of the interior global ocean based on surface satellite observations is important for understanding complex multidimensional dynamic processes within ocean. This study proposes a new ensemble learning algorithm, extreme gradient boosting (XGBoost), retrieving subsurface anomalies, including temperature anomaly (STA) salinity (SSA), in upper 2000 m The model combines situ Argo data estimation, uses root-mean-square...

Primary production (PP) of the South China Sea (SCS) basin area (waters depth deeper than 200 m) is estimated using satellite products, with an overarching goal to reliably characterize spatial distribution and temporal variation PP this important marginal sea. Among models used, absorption-based model (AbPM) showed better performance ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$R^{2}=0.47$...

Abstract Marine heatwaves (MHWs) are extremely warm ocean temperature events that significantly affect marine environments, but their effects on the coastal carbonate system still uncertain. In this study, we systematically quantify MHWs' impacts air‐sea carbon dioxide (CO 2 ) flux anomalies (FCO ′) in Mid‐Atlantic Bight (MAB) and South Atlantic (SAB) from 1992 to 2020. During longest MHW both regions, oceanic CO uptake capabilities substantially decreased, primarily due significant...

Coastlines are fundamental to humans for habitation, commerce, and natural resources. Many coastal ecosystem disasters, caused by extreme sea surface temperature (SST), were reported when the global climate shifted from warming hiatus after 1998. The task of understanding SST variations within context is an urgent matter. Our study on 1982 2013 revealed a significant cooling trend in low mid latitudes (31.4% coastlines) 1998, while 17.9% coastlines changed concurrently. reversals Northern...

Abstract For this paper, a coupled physical‐biological model was developed in order to study the mechanisms of winter bloom Luzon Strait (referred as LZB). Based on simulation for January 2010, results showed that capable reproducing key features LZB, such location, inverted‐V shape, twin‐core structure and intensity. The LZB occurred during relaxation period intensified northeasterly winds, when deepened mixed layer started shoal. Nutrient diagnostics vertical mixing responsible nutrient...

Retrieving information concerning the interior of ocean using satellite remote sensing data has a major impact on studies dynamic and climate changes; however, lack within limits such about global ocean. In this paper, an artificial neural network, combined with gridded Argo product, is used to estimate heat content (OHC) anomalies over four different depths down 2000 m covering near-global ocean, excluding polar regions. Our method allows for temporal hindcast OHC other periods beyond...

As the most relevant indicator of global warming, ocean heat content (OHC) change is tightly linked to Earth’s energy imbalance. Therefore, it vital study OHC and absorption redistribution. Here we analyzed characteristics variations based on a previously reconstructed dataset (named OPEN) with four other gridded datasets from 1993 2021. Different datasets, OPEN directly obtains through remote sensing, which reliable superior in reconstruction, further verified by Clouds Radiant Energy...

Abstract. Typhoons are very unpredictable natural disturbances to subtropical mangrove forests in Asian countries, but little information is available on how these affect ecosystem level carbon dioxide (CO2) exchange of wetlands. In this study, we examined short-term effect frequent strong typhoons defoliation and net CO2 (NEE) mangroves, also synthesized 19 during a 4-year period between 2009 2012 further investigate the regulation mechanisms water fluxes following typhoon disturbances....

Abstract. Insufficient spatiotemporal coverage of observations the surface partial pressure CO2 (pCO2) has hindered precise carbon cycle studies in coastal oceans and justifies development spatially temporally continuous pCO2 data products. Earlier products have difficulties capturing heterogeneity regional variations decadal trends North American Atlantic Coastal Ocean Margin (NAACOM). This study developed a reconstructed product for NAACOM (Reconstructed Acidification Database-pCO2, or...

Abstract. Biological productivity in the summer Vietnam boundary upwelling system western South China Sea, as many coastal systems, is strongly modulated by wind. However, role of ocean circulation and mesoscale eddies has not been elucidated. Here, we show a close spatiotemporal covariability between primary production kinetic energy. High associated with high energy, which accounts for ∼15 % variability. Results from physical–biological coupled model reveal that elevated energy linked to...

In the northern South China Sea of western Pacific Ocean during winter, clouds, sun glint, and other factors block optic sensors, leading to a high missing rate hence major concern in ocean color products such as chlorophyll-a (CHL) data. These constraints inhibit understanding CHL variabilities at short (< seasonal) scales. Here, we introduce new gap-filling method reconstruct data gaps daily remote sensing product. We applied discrete cosine transform with penalized least square (DCT-PLS)...

Remote sensing study of the carbon cycle in coastal marine systems using machine learning methods has received significant attention recently. The partial pressure dioxide (CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ) seawater ( <italic xmlns:xlink="http://www.w3.org/1999/xlink">p</i> CO xmlns:xlink="http://www.w3.org/1999/xlink">2w</sub> is a crucial parameter for quantifying air-sea exchange. However, previous studies did not...

Global ocean heat content (OHC) is generally estimated using gridded, model and reanalysis data; its change crucial to understanding climate anomalies warming phenomena. However, Argo gridded data have short temporal coverage (from 2005 the present), inhibiting of long-term OHC variabilities at decadal multidecadal scales. In this study, we utilized multisource remote sensing based on long short-term memory (LSTM) neural network method, which considers dependence reconstruct a new...