According to a Phys.org article, ship emissions caused more than 1,200 ozone-related and 2,500 particulate-related premature deaths in the Pearl River Delta region in 2015, says a new research in the AGU journal GeoHealth.
Coastal Emission Controls?
The new study also predicts that implementing new coastal emission controls could reduce mortality due to fine particulates by 30 percent and ozone by 10 percent by 2030.
How the Delta is effected?
During the past few decades, the fertile, low-lying delta in southeastern China where the Pearl River flows into the South China Sea has become the world’s largest and most densely populated urban region. This megalopolis now encompasses nine major cities, including Hong Kong, Shenzhen and Guangzhou, with a combined population of about 65 million and a GDP equivalent to South Korea’s.
A boom in shipping has contributed to the region’s explosive growth. In 2015, the delta’s 11 major ports, which include three of the 10 largest in the world, handled about 39 percent of China’s total exports.
Ship Emission Studies
Ship emissions are major sources of fine particulate matter, inhalable soot particles with a diameter less than or equal to 2.5 microns, as well as volatile organic carbons (VOCs), and nitrogen oxides. In the presence of sunlight in Earth’s atmosphere, some nitrogen oxides and VOCs can react together to form ozone. Both ozone and fine particulate matter are pollutants known to adversely affect human health and whose impacts are typically measured in terms of premature deaths.
The study’s authors used the 3-D Weather Research and Forecasting Model coupled with Chemistry to assess the delta’s air quality both with and without ship emissions and then compared the results to determine the concentrations of pollutants that ships contribute to the region.
How were the studies done?
Next, the researchers used previous studies that analyzed the health outcomes associated with increased exposure to ozone and fine particulates to estimate the impact that ship emissions had on human health in 2015, the last year for which ship and land emission inventories were available. They found ship emissions caused more than 1,200 ozone-related and 2,500 particulate-related premature deaths in the Pearl River Delta region in 2015.
The team then used the same approach to predict the impacts of shipping emissions in the delta in 2030. Taking estimates of future ship fuel consumption and fuel quality into account, the team conducted simulations for several scenarios, including both with and without the implementation of an Emission Control Area (ECA), an internationally designated zone where ships must use low-sulfur fuels and take other actions to minimize their harmful emissions.
In 2015, ship emissions increased summer PM2.5 concentrations and O3 mixing ratios by 1.4 μg/m3 and 1.9 ppb, respectively, within the Pearl River Delta (PRD), China, according to a new study by a team from Emory University and the International Council on Clean Transportation (ICCT), says a report published in the Green Car Congress.
Premature Deaths
This resulted in an estimated 466 and 346 excess premature acute deaths from PM2.5 and O3, respectively, according to the study. Premature mortality from chronic exposures was even more significant, with 2,085 and 852 premature deaths from ship-related PM2.5 and O3, respectively. The open-access paper is published in the AGU journal GeoHealth.
How Ship Emissions Affected It?
The team also projected ship emissions in 2030 with and without an ECA, using two possible land scenarios.
- With an ECA, the researchers predicted 76% reductions in SO2 and 13% reductions in NOx from the shipping sector.
- Assuming constant land emissions from 2015 in 2030 (2030 Constant scenario), they found that an ECA could avoid 811 PM2.5-related and 108 O3-related deaths from chronic exposures.
- Using a 2030 projected scenario for land emissions, they found that an ECA would avoid 1,194 PM2.5-related and 160 O3-related premature deaths in 2030.
- In both scenarios, implementing an ECA resulted in 30% fewer PM2.5-related premature deaths and 10% fewer O3 -related premature deaths, illustrating the importance of reducing ship emissions.
- China, as the world’s largest product exporter, has substantial air quality and health risks associated with ship emissions.
- China owns nearly 5,000 ocean going vessels (OGVs) with a total capacity of over 160 million tons and handled approximately one quarter of the world throughput in its container ports in 2015.
- The three biggest port clusters in China are the Pearl River Delta (PRD), the Yangtze River Delta (YRD) and the Bohai Sea Rim (BR).
- The PRD port cluster, located in southern China, handled roughly 39% of all exports from China in 2015.
- The PRD port cluster has 11 major ports and three of them, Shenzhen, Hong Kong and Guangzhou ports, are all ranked among the top ten largest container ports by TEU (Twenty-foot Equivalent Unit) volume in the 107 world.
- At the same time, over 58 million residents lived in the central PRD region in 2015 and two megacities, Guangzhou and Shenzhen, had over 13 and 11 million residents, respectively.
Therefore, how the emissions from oceangoing ships might pollute the air and threaten the health of local residents is of particular importance.
… Results show that ship emissions caused major environmental and health impacts in 2015 in PRD and will continue to do so in 2030. Implementing an ECA would improve air quality substantially and reduce premature mortality in the PRD region of China. We also found that an ECA is effective for PRD, regardless of land emissions.
How will ECA help?
The results indicate that implementing an ECA would generate substantial health benefits, including 30 percent fewer particulate-related and 10 percent fewer ozone-related premature deaths, in the region.
Collectively, the team’s findings indicate that ship emissions are already impacting human health in the Pearl River Delta and will continue to do so in the near future. Implementing an ECA would substantially improve the air quality and decrease premature deaths in the region, according to the study’s authors.
“Based upon these results, we think it is important for China to consider implementing an ECA,” concluded Chen, a former Emory University graduate student and the lead author of the new study, who is currently a data analyst at the Center on Rural Innovation.
Although a number of recent studies have analyzed the impact of ship emissions in China, the new research appears to be the first that estimates both past and future air quality and health impacts in the Pearl River Delta region, said Eri Saikawa, an environmental science professor at Emory University and a co-author of the new study.
“The results have implications beyond the Pearl River Delta,” she said. “We would expect similar results all along the Chinese coastlines.”
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Source: Phys.org
