Diverse changes in shipping emissions around the Western Pacific ports under the coeffect of the epidemic and fuel oil policy.

The Western Pacific Ocean (the WPO), as one of the busiest shipping areas in the world, holds a complex water traffic network. In 2020, the International Maritime Organization (IMO) low-sulfur fuel regulations were implemented globally, while the COVID-19 outbreak influenced shipping activities together. This study aimed to assess the combined impact of epidemics and low-sulfur fuel policies on ship emissions, as well as their environmental effects on the WPO.

Impact of air emissions from shipping on marine phytoplankton growth.

With the rapid expansion of maritime traffic, increases in air emissions from shipping have exacerbated numerous environmental issues, including air pollution and climate change. However, the effects of such emissions on marine biogeochemistry remain poorly understood. Here, we collected ship-emitted particles (SEPs) from the stack of a heavy-oil-powered vessel using an onboard emission test system and investigated the impact of SEPs on phytoplankton growth over the northwest Pacific Ocean (NWPO).

Projection of ship emissions and their impact on air quality in 2030 in Yangtze River delta, China.

China has been in the implementation phase of Domestic Ship Emission Control Areas (DECAs) regulation to reduce emissions of air pollutants from ships near populated areas since 2016. The Yangtze River Delta (YRD) is one of the busiest port clusters in the world, accounting for 11% of global seaborne cargo throughput, so future improvements in shipping emission controls may still be important in this region. To assess the impact of future ship emissions on air quality of coastal areas, this study evaluates emissions reductions and air quality in 2030 for three scenarios (business as usual, stricter regulations, and aspirational policies) representing increasing levels of control compared with a base year of 2015.

Modeling the impact of marine DMS emissions on summertime air quality over the coastal East China Seas.

[1] Biogenic emission of dimethyl sulfide (DMS) from seawater is the major natural source of sulfur into the atmosphere. In this study, we use an advanced air quality model (CMAQv5.2) with DMS chemistry to examine the impact of DMS emissions from seawater on summertime air quality over China.

Impact of dimethylsulfide chemistry on air quality over the Northern Hemisphere.

We implement oceanic dimethylsulfide (DMS) emissions and its atmospheric chemical reactions into the Community Multiscale Air Quality (CMAQv53) model and perform annual simulations without and with DMS chemistry to quantify its impact on tropospheric composition and air quality over the Northern Hemisphere. DMS chemistry enhances both sulfur dioxide (SO) and sulfate ( ) over seawater and coastal areas. It enhances annual mean surface SO concentration by +46 pptv and by +0.

Regional and Urban-Scale Environmental Influences of Oceanic DMS Emissions over Coastal China Seas.

Marine biogenic dimethyl sulfide (DMS) is an important natural source of sulfur in the atmosphere, which may play an important role in air quality. In this study, the WRF-CMAQ model is employed to assess the impact of DMS on the atmospheric environment at the regional scale of eastern coastal China and urban scale of Shanghai in 2017. A national scale database of DMS concentration in seawater is established based on the historical DMS measurements in the Yellow Sea, the Bohai Sea and the East China Sea in different seasons during 2009~2017.

Cool Roof and Green Roof Adoption in a Metropolitan Area: Climate Impacts during Summer and Winter.

This study, for the first time, estimates the climate impacts of adopting green roofs and cool roofs on the seasonal urban climate of 16 cities that comprise the Yangtze River Delta metropolitan. We use a suite of regional climate simulation to compare the local climate impacts of the implementation of different roof strategies in summer and winter. The results indicate that in summer, the 2 m surface temperature reduced significantly when these two roof strategies are adopted, with peak reductions of 0.

Increasing surface ozone and enhanced secondary organic carbon formation at a city junction site: An epitome of the Yangtze River Delta, China (2014-2017).

This study aims to understand the characteristics of surface ozone (O), search for factors affecting the variations in its concentration, and estimate its impacts on the secondary organic carbon (SOC) levels and atmospheric oxidation capacities in the Yangtze River Delta (YRD). Four years of continuous observations (2014-2017) of the surface O, organic carbon, elemental carbon, nitrogen oxides, PM and meteorological factors along with three years of measurements (2015-2017) of the concentrations of 56 volatile organic compounds were conducted at a rural site. Our measurements showed that the total number of O pollution days more than doubled over the four-year period, from 28 days in 2014 to 76 days in 2017.

Changes in the SO Level and PM Components in Shanghai Driven by Implementing the Ship Emission Control Policy.

This study aims to understand the effect of the Domestic Emission Control Area (DECA) policy on ambient SO and particle components in Shanghai. Online single particle analysis and SO measurements from 2015 to 2017 were compared to analyze the long-term variations before and after the DECA policy. Our study showed that there was a significant decrease in SO by 27-55% after the implementation of the DECA policy.