ICCT studies air pollution from ships in Greater Pearl River Delta

The International Council on Clean Transportation (ICCT) issued a new study, compiling a ship emissions inventory in China’s Greater Pearl River Delta (GPRD), a heavily populated and prosperous region with heavy ship traffic.

As this traffic contributes to poor local air quality, the Chinese government has identified the GPRD region as a key target for steps to control emissions from ships.

China is the world’s second largest economy and the largest trading nation in the world. Its coastline is visited by thousands of cargo-carrying ships on a daily basis. Upon establishment of the Pearl River Delta Domestic Emission Control Area (DECA), ships operating within approximately 12 nautical miles beyond China’s coastal baseline must gradually switch to cleaner marine fuels (Mao, 2016). Upon evaluation of the effectiveness of the current DECA, China may consider taking additional actions as soon as 2020.

Conclusions

• In 2015, OGVs emitted 104 thousand tonnes (kilotonnes) of sulfur oxides (SOX), 14 kt of particulate matter (PM), and 150 kt of nitrogen oxides (NOX). This is approximately 24%, 3%, and 17% of respective emissions from all sources in the PRD region.
• Container ships alone emitted about 60% of all air pollution from OGVs in 2015, making them a clear target of future air pollution control policies. Bulk carriers and oil tankers were also important contributors to total emissions.
• In the study region, about 9% of total emissions were emitted at berth. This share increased to 63% at the 12-nm boundary and then continued to increase mildly moving further away. The 96-nm boundary captured about 82% of total emissions. Expanding the current DECA regulations to 12 nm would reduce emissions roughly 7 fold. Further expansion, for example via an international emission control area (ECA) out to 100 nm, would provide even greater benefits.

Credit: ICCT

The report suggests that a four-step approach could be used to evaluate the health benefits of a potential vessel emission control policy scenario:

1. Model emissions of criteria pollutants from vessels and other emission sources under policy and business-as-usual (BAU) scenarios, respectively;
2. Model ambient PM2.5 and ozone concentrations under these scenarios using chemical transport models (e.g., CMAQ) together with corresponding meteorological data;
3. Estimate health impacts in terms of premature death and morbidities using exposure– response functions for specific health outcomes in combination with demographic and health incidence data; and
4. Determine the health benefits of policy action by comparing results of the BAU and policy scenarios.

Explore more by reading the full report: