Abstract Phytoplankton blooms in coastal marine environments are regard as a double-edged sword, offering benefits to coastal ecosystems while also posing significant environmental challenges. The occurrence and severity of these blooms are influenced by environmental factors, with climate oscillations playing a crucial role. In this study, we employed two time-frequency analysis methods to investigate the teleconnection between phytoplankton blooms (denoted by bloom intensity, BI) and El Niño–Southern Oscillation (ENSO) from 2003 to 2020 in eight large marine ecosystems (LMEs) of Western Nort ..read more

Abstract Using eddy-resolving Community Earth System Model (CESM) simulations, this study investigates mesoscale eddy energetics and the role of air-sea interaction for both anticyclonic and cyclonic eddies (AEs and CEs) in the Kuroshio Extension (KE) region. Based on energy budget analysis and eddy tracking algorithm, it is found that eddy energy balance depicts similar characteristics for AEs and CEs. The eddy kinetic energy (EKE) is generated through barotropic instability, vertical buoyancy flux, as well as transported from the upper stream Kuroshio. In addition, the temperature variance ..read more

Abstract The Gulf of Maine (GOM) is one of the most productive and ecologically important marine environments on the planet. The Gulf of Maine Coastal Current (GMCC), which stretches along the western side of the GOM from the Bay of Fundy to Cape Cod, plays an important role in supporting this productivity by transporting nutrients, larvae and dinoflagellates southwestward along the Canadian and New England coastlines. Climate change has led to alterations in GOM ecosystems in recent years: GOM water temperatures have warmed and distributions of marine species have shifted. However, the impact ..read more

Abstract The eastern subpolar North Atlantic is a source of nutrients to the Northwest European Shelf and Arctic; however, biogeochemical transports in this important region are unknown. We examine variability in nutrients and carbon at the eastern boundary of the subpolar North Atlantic between 2017 and 2020, and calculate their transport by a branch of the North Atlantic Current and the European Slope Current. By combining observations from moorings and ship-based surveys, we derive novel biogeochemical property transports at high temporal resolution. Data from 63 m provide new evidence ..read more

Abstract The northern Indian Ocean, typically the Bay of Bengal (BoB), has experienced several stronger tropical cyclones during the pre-monsoon season in the last few years. Similarly, in 2021, cyclone Yaas reached the Very Severe Cyclonic Storm (VSCS) stage despite forming above 14°N. In comparison to the other three cyclones that formed in 2007 (Akash), 2009 (Aila), and 2017 (Mora) with a similar cyclogenesis location and track, the pre-cyclonic condition in 2021 is more favorable. It was found that from 2007 to 2021, the area associated with Sea Surface Temperature greater than 31°C increa ..read more

Abstract The access of heat to the Antarctic ice shelf cavities is regulated by the Antarctic Slope Front, separating relatively warm offshore water masses from cold water masses on the continental slope and inside the cavity. Previous observational studies along the East Antarctic continental slope have identified the drivers and variability of the front and the associated current, but a complete description of their seasonal cycle is currently lacking. In this study, we utilize two years (2019–2020) of observations from two oceanographic moorings east of the prime meridian to further detail ..read more

Abstract Interannual variations in upper ocean salinity in the North Pacific Ocean (NP) were examined comprehensively over a period of 18 years (2004–2021) with gridded data sets considering vertical profiles of salinity. The salinity in nearly half of the basin varied in phase with a slight lag, and the rest of the basin exhibited the opposite phase on a decadal scale. The average salinity above 400 dbar prominently increased in the eastern and western mid-latitude regions from approximately 2010 to the latter half of the 2010s, and decreased in the central subarctic and subtropics ..read more

Abstract Consecutive Argo float profiles are used to observe upper ocean changes resulting from the passage of tropical cyclones (TCs) in the South Pacific between 2001 and 2023. Cross-sectional composites of the ocean response are produced by normalizing the distance between the profile and cyclone track by the 34-knot wind radius (R34) of each TC to better resolve the average changes in water properties. Surface cooling in the initial mixed layer (ML) extends from the center to about twice R34 and is stronger to the left of the TC track. Subsurface warming at the base of the ML is observed b ..read more

Abstract The California Current Ecosystem (CCE) is a natural laboratory for studying the chemical and ecological impacts of ocean acidification. Biogeochemical variability in the region is due primarily to wind-driven near-shore upwelling of cold waters that are rich in re-mineralized carbon and poor in oxygen. The coastal regions are exposed to surface waters with increasing concentrations of anthropogenic CO2 (Canth) from exchanges with the atmosphere and the shoreward transport and mixing of upwelled water. The upwelling drives intense cycling of organic matter that is created through photo ..read more

Abstract In the northeastern tropical Atlantic, a region of high potential vorticity (PV) determines the size of the exchange window for the interior thermocline flow of the subtropical cell via its variations in strength and extent. Variability of this PV barrier has the potential to impact the ventilation of the tropical Atlantic on decadal timescales. Here, the impact of the North Atlantic Oscillation (NAO) on the PV barrier related to isopycnals within the thermocline of the subtropical-tropical Atlantic Ocean is assessed from Argo observations for the time period of 2006–2022. Relative to ..read more