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Submesoscale processes significantly influence the air‐sea interaction, heat budget and the distribution of physical and biogeochemical tracers in the upper‐ocean. We study the spatiotemporal characteristics and generation mechanisms of submesoscale vertical heat transport (SVHT) at the Kuroshio Extension using a submesoscale‐permitting simulation. Compared with the commonly used Boxcar and Hanning filters, the clean‐cut feature of the Butterworth filter in the wavenumber domain makes it a proper filter to diagnose SVHT. SVHT is systematically upward, peaking in winter. Through causality analysis, we find that, among the basic factors (mixed layer depth, strain rate, surface wind stress, and horizontal buoyancy gradient) from the conventional submesoscale generation mechanism scalings, mixed layer depth plays the leading role in modulating the intraseasonal variation of SVHT. Using the budget of submesoscale temperature variance and causality analysis, we find that advection also plays an important role in regulating SVHT. This work suggests that the choice of appropriate spatial filter is important for SVHT diagnosis and including advection may help improve submesoscale parameterization schemes. Plain Language Summary: Ocean currents with horizontal spatial scales of O(0.1–10) km and temporal scales of hours‐days are defined as submesoscale processes. Submesoscale processes are characterized by large vertical velocity, driving significant vertical heat transport. In this study, we investigate the spatiotemporal features of submesoscale vertical heat transport (SVHT) and the corresponding mechanisms in the Kuroshio Extension region using a high‐resolution numerical simulation. We find that the diagnostics of SVHT is sensitive to the extraction method of submesoscale processes based on spatial scales. SVHT is systematically upward with pronounced seasonal variability, reaching its peak in winter. The intraseasonal variation of SVHT is controlled by multiple factors simultaneously, among which the mixed layer depth plays the most important role. Advection also has influence on SVHT variability. This study offers a better understanding of the dynamic mechanisms driving SVHT, while also highlights the importance of proper filter selection in SVHT diagnostics. Key Points: The estimation of submesoscale vertical heat transport is sensitive to the choice of spatial filterAmong the conventional factors, mixed layer depth is the top regulator of the submesoscale vertical heat transport intraseasonal variationThe advection process can also modulate the intraseasonal variability of submesoscale vertical heat transport [ABSTRACT FROM AUTHOR]

Bay scallops (Argopecten irradians; A. irradians) are shellfish with high nutritional and economic value. However, nutritional studies on A. irradians with different shell colors are limited. This study examines the hazardous, nutritional, and taste-contributing compounds during the growth of A. irradians with different shell colors. During the growth of A. irradians, the hazardous contents were below the standard limit. Changes in the nutritional and taste-contributing compounds between months were more significant than shell color. Bay scallops had more fats, total fatty acids, and taste-contributing compounds in August and more proteins, essential fatty acids, vitamin D, vitamin B12, Cu, and Zn in September and October. In October, the golden shell color strain had more proteins, essential fatty acids, vitamin D, vitamin B12, Cu, and Zn, while the purple shell color strain had more taste-contributing compounds. A. irradians had better taste in August and higher nutritional value in September and October. In October, the golden shell color strain has higher nutritional value, and the purple shell color strain has better commercial value and taste. The correlation analysis indicates that the nutritional quality of bay scallops is affected by age (months), shell color, and seawater environment. [ABSTRACT FROM AUTHOR]