Toxicity assessment of atmospheric particulate-bound polycyclic aromatic hydrocarbons on marine phytoplankton.

Particulate-phase polycyclic aromatic hydrocarbons (PAHs), known for their stability and significant toxicity, can undergo long-range atmospheric transport and deposit into oceans. However, their impact on phytoplankton remains controversial. We extracted PAH-containing mixtures from aerosol particulate matter (AP-PAHs) and assessed their toxicity on coastal diatom Skeletonema costatum under environmentally relevant exposure levels (0.

Consecutive haze and dust pollution drives episodic atmospheric phosphorus enrichment and dry deposition over China's marginal seas.

Atmospheric pollution events can trigger pulsed phosphorus deposition into the ocean, rapidly altering nutrient dynamics. Haze and dust event differ markedly in sources, particle sizes, and ecological impacts. This study investigates atmospheric P concentrations and dry deposition during a consecutive haze-dust episode in November 2018 over China's marginal sea.

Contrasting Effects of Atmospheric Particulate Matter Deposition on Free-Living and Particle-Associated Bacteria in the South China Sea.

Atmospheric particulate matter (PM) deposition has become an important nutrient source in marine ecosystems, increasing particulate organic carbon and resource heterogeneity. However, their effects on marine bacterial communities remain unclear. In this study, by conducting on-board microcosm experiments with anthropogenic East Asian PM in the oligotrophic South China Sea, the response of particle-associated (PA) bacteria was investigated and compared with its free-living (FL) counterparts.

Habitat-Dependent DNA viral communities in atmospheric aerosols: Insights from terrestrial and marine ecosystems in East Asia.

The transmission of viruses through aerosols is of growing public health concern, yet research on aerosol-associated viral communities lags behind that of terrestrial and aquatic ecosystems. Here, DNA viral diversity in natural aerosols from both over land and ocean in the East Asia region was examined. The results showed that atmospheric environments harbor a distinct viral community that differs from those present in terrestrial and aquatic ecosystems.

Alkaline phosphatase-mediated hydrolysis of dissolved organic phosphorus enhances phosphorus cycling in the Yellow Sea.

The utilization of dissolved organic phosphorus (DOP) driven by alkaline phosphatase hydrolysis contributes significantly to mitigating coastal nitrogen pollution through alleviating phosphorus (P) limitation. However, the lack of a parameterization for this process limits the quantitative assessment of its impact on marine nutrient pollution and cycling. Our study addresses this issue using data from a series of on-board microcosm experiments conducted in the Yellow Sea, where P limitation prevails.

Intensification of future subsurface marine heatwaves in an eddy-resolving model.

A shift in depth range enables marine organisms to adapt to marine heatwaves (MHWs). Subsurface MHWs could limit this pathway, yet their response to climate warming remains unclear. Here, using an eddy-resolving Earth system model forced under a high emission scenario, we project a robust global increase in subsurface MHWs driven by rising subsurface mean temperatures and enhanced temperature variability.

Effect of ocean dynamic processes on the temporal-spatial pattern of persistent organic pollutants (PCB-153 and BDE-47) in the shelf seas.

Field observations of persistent organic pollutants (POPs) in shelf seas presented abnormal phenomena such as high-concentration patches in offshore areas and different vertical profiles of POPs at the same location. We assumed that these phenomena were associated with the presence of bottom cold water mass (BCWM) in shelf seas and used a hydrodynamic-ecosystem-POP coupled model to confirm this hypothesis. Based on model results, with the formation of BCWM during summer, POPs accumulated inside BCWM due to their transport across the thermocline by the sorption to sinking particles.

Marine sources of formaldehyde in the coastal atmosphere.

Elevated concentrations of formaldehyde and other carbonyl compounds are frequently observed in the marine atmosphere but are often significantly underestimated by atmospheric models. To evaluate the potential impact of marine sources on atmospheric formaldehyde, high-resolution measurements were conducted at a coastal site (∼15 m from the sea) during the summer in Qingdao, China. Observed formaldehyde levels averaged 2.

Statistical analysis and environmental impact of pre-existing particle growth events in a Northern Chinese coastal megacity: A 725-day study in 2010-2018.

Pre-existing particles usually constitute the major fraction of atmospheric particles, except during some episodes in the presence of strong emissions and/or secondary generation of fresh particles. Previous case studies have investigated the growth of pre-existing particles and their potential environmental and climate impacts. However, there is limited knowledge about the statistical characteristics of these growth events and related effects.

Settling velocity of atmospheric particles in seawater: Based on hydrostatic sedimentation method using video imaging techniques.

When atmospheric particles deposit to the ocean, their settling velocities and residence times associated are critical for their effects on oceanic ecosystems. We developed a hydrostatic sedimentation method using video imaging techniques to track particles of 5-20 μm in diameter falling into seawater and determine the particle settling velocities in relation to their diameter, shape, organic matter contained, and seawater salinity. The measured settling velocities varied from 0.

Atmospheric deposition and river runoff stimulate the utilization of dissolved organic phosphorus in coastal seas.

In coastal seas, the role of atmospheric deposition and river runoff in dissolved organic phosphorus (DOP) utilization is not well understood. Here, we address this knowledge gap by combining microcosm experiments with a global approach considering the relationship between the activity of alkaline phosphatases and changes in phytoplankton biomass in relation to the concentration of dissolved inorganic phosphorus (DIP). Our results suggest that the addition of aerosols and riverine water stimulate the biological utilization of DOP in coastal seas primarily by depleting DIP due to increasing nitrogen concentrations, which enhances phytoplankton growth.

Isotopic comparison of ammonium between two summertime field campaigns in 2013 and 2021 at a background site of North China.

Ammonia (NH) is the primary atmospheric alkaline gas, playing a crucial role in the atmospheric chemistry. Recently, non-agricultural emissions have been identified as the dominant sources of NH in urban areas. However, few studies have quantified the contributions of different sources to regional NH.

Important Roles and Formation of Atmospheric Organosulfates in Marine Organic Aerosols: Influence of Phytoplankton Emissions and Anthropogenic Pollutants.

Organosulfates (OSs) could be potentially important compounds in marine organic aerosols, while their formation in marine atmospheres is far from clear due to a lack of cruise observations. In this work, shipboard atmospheric observations were conducted over the Yellow Sea and Bohai Sea to investigate the abundance and formation of biogenic isoprene/monoterpene-OSs in marine aerosols. The quantified OSs and NOSs accounted for 0.

Impacts of model resolution and ocean coupling on mean and eddy momentum transfer during the rapid intensification of super-typhoon (2011).

This study uses a coupled atmosphere-ocean model with different numerical settings to investigate the mean and eddy momentum transfer processes responsible for Typhoon 's (2011) early rapid intensification (RI). Three experiments are conducted. Two use the coupled model with a horizontal resolution of either 1 km (HRL) or 3 km (LRL).

Phosphorus and its solubility in aerosols from continental and marine sources in the sea areas near China: Results from a 40-day cruise mission in late spring.

Accurate assessments of soluble phosphorus (P) in aerosol particles are essential to understand the atmospheric nutrients supply to the marine ecosystem. We quantified total P (TP) and dissolved P (DP) in the aerosol particles collected in the sea areas near China in a cruise mission from May 1 to June 11, 2016. The overall concentrations of TP and DP were 3.

Atmospheric dry deposition fluxes of trace metals over the Eastern China Marginal Seas: Impact of emission controls.

Atmospheric deposition is an important exogenous input of trace metals to Eastern China Marginal Seas (ECMS), which is strongly affected by human activities. With emission control practices implemented in China, it still remains unknown what changes have taken place in the atmospheric dry depositions of the trace metals over ECMS. This study aimed to estimate the atmospheric dry depositions of Zn, Pb, Cu, and Cd over ECMS via Weather Research and Forecasting Model-Community Multiscale Air Quality Modeling System (WRF-CMAQ) in the two winter periods of January 2012 and January 2019 as well as to explore the impacts of emission control on the depositions.

Environmental factors driving the formation of water-soluble organic aerosols: A comparative study under contrasting atmospheric conditions.

Water-soluble organic carbon (WSOC), as major fractions of atmospheric aerosols, have gained attention due to their light-absorption properties. To illustrate the sources and key environmental factors driving WSOC formation under different atmospheric conditions, a comparative study was conducted by summarizing the results obtained from five field campaigns at inland (urban, suburban or regional) sites and a coastal site during different seasons. Organic carbon concentrations varied from 8.

Interannual variations in the nutrient cycle in the central Bohai Sea in response to anthropogenic inputs.

In recent decades, there has been growing concern regarding the effects of human activities on the coastal nutrient cycle. However, interannual variations in the coastal nutrient cycle in response to anthropogenic nutrient input have rarely been quantified. In this study, a hydrodynamic-ecological model capable of describing the nitrogen and phosphorus cycles was used to analyze interannual variations in the nutrient cycle in the central Bohai Sea, a typical semi-enclosed sea in the Northwest Pacific.

Striking impacts of biomass burning on PM concentrations in Northeast China through the emission inventory improvement.

Biomass burning exerts substantial influences on air quality and climate, which in turn to further aggravate air quality. The biomass burning emissions in particular of the agricultural burning may suffer large uncertainties which limits the understanding of their impact on air quality. Based on an improved emission inventory of the Visible Infrared Imaging Radiometer Suite (VIIRS) relative to commonly used Global Fire Emissions Database (GFED), we thoroughly evaluate the impact of biomass burning on air quality and climate during the episodes of November 2017 in Northeast China which is rich in agriculture burning.

The occurrence of lower-than-expected bulk N values over the marginal seas of China - Implications for competitive activation of marine aerosols.

In this study, we combined the measured bulk particle number concentration (N), particle number size distribution (PNSD) and bulk cloud condensation nuclei concentration (N) at various supersaturation (SS) levels to investigate competitive activation of aerosols in the marine atmospheres over the marginal seas of China during two winter campaigns Campaign A (December 9-19, 2019) and Campaign B (December 28, 2019-January 16, 2020). During the two campaigns, we observed various categories of aerosols, i.e.

Aerosol Iron Solubility Specification in the Global Marine Atmosphere with Machine Learning.

Aerosol iron (Fe) solubility is a key factor for the assessment of atmospheric nutrients input to the ocean but poorly specified in models because the mechanism of determining the solubility is unclear. We develop a deep learning model to project the solubility based on the data that we observed in a coastal city of China. The model has five variables: the size range of particles, relative humidity, and the ratios of sulfate, nitrate and oxalate to total Fe (TFe) contents in aerosol particles.

Effect of Anthropogenic Aerosol Addition on Phytoplankton Growth in Coastal Waters: Role of Enhanced Phosphorus Bioavailability.

Atmospheric deposition can supply nutrients to induce varying responses of phytoplankton of different sizes in the upper ocean. Here, we collected surface and subsurface chlorophyll maximum (SCM) seawaters from the Yellow Sea and East China Sea to conduct a series of onboard incubation experiments, aiming to explore the impact of anthropogenic aerosol (AR, sampled in Qingdao, a coastal city in Northern China) addition on phytoplankton growth using schemes with (unfiltered seawater, UFS) and without (filtered seawater, FS) microsized (20-200 μm) cells. We found that AR addition stimulated phytoplankton growth obviously, as indicated by chlorophyll (Chl ) in surface incubations, and had stimulatory or no effects in SCM incubations, which was related to nutrient statuses in seawater.

Threat by marine heatwaves to adaptive large marine ecosystems in an eddy-resolving model.

Marine heatwaves (MHWs), episodic periods of abnormally high sea surface temperature (SST), severely affect marine ecosystems. Large Marine Ecosystems (LMEs) cover ~22% of the global ocean but account for 95% of global fisheries catches. Yet how climate change affects MHWs over LMEs remains unknown, because such LMEs are confined to the coast where low-resolution climate models are known to have biases.