SOURCE APPORTIONMENT HKUST has been playing a leading role in providing evidence for local and regional air pollution control measures. Among the various powerful tools, "Source Apportionment Method" has been demonstrating as the most effective model in resolving spatiotemporal distribution and composition of air pollutants in a particular region/location.
EMISSIONS MEASUREMENT 3 Approaches: METHOD
Since 2003, IENV has been dedicating research efforts on Source Apportionment Studies to elucidate the underlying contribution profile of air pollutants in Hong Kong. Groundbreaking research findings generated in 2009 provided first time a clear picture to the top question about relative POLLUTION DATABASE significance of local vs. regional sources for Hong Kong's air pollution. Continuous efforts paid in recent years have generated remarkable policy intervention hence encouraging air quality improvements in Hong Kong.
SIGNIFICANCE
DRAWBACKS
TOTAL EMISSION
It is useful on a regional scale to depict the volumnes (in tonnage) emitted from different sources
Difficult to give quantitative estimate of individual pollutants' contribution in particula location
SOURCE APPORTIONMENT
Based on "Receptor Models" and chemically speciated data to apportion air pollution component abundances
In-depth understanding of prevailing environmental conditions as well as expertise in analysing environmental data is needed
TIME-BASED APPORTIONMENT
It shows air pollution component abundances in terms of number of days
Particular trace gas (e.g. SO2) might be overshadowed by local sources over a period of time hence overestimating its contribution
© 2018 Institute for the Environment, HKUST
MILESTONES & POLICY IMPLICATIONS for HONG KONG
Provided scientific evidence for the review & revamping of Ocean Going Vessels (OGVs) Emission Inventory; hence leading to the design and deployment of ship emission control measures
MASSIVE REDUCTION (60-80%) in SO 2 EMISSIONS
2009 - 2015
Dedicated research efforts on Source Apportionment
Provided scientific evidence for the review & revamping of Hong Kong Emission Inventory; hence leading to revamping of HKEPD's PATH Model 2007 - 2012
2003 - 2007
SOURCE APPORTIONMENT IN APPLICATION Local vs Regional Sources?
10%
90%
40%
60%
TIME-BASED APPORTIONMENT analysis showed that about 90% of a year failed in reaching the World Health Organization's Air Quality Guideline (AQG).
TIME-BASED APPORTIONMENT analysis also showed that about 40% of the 'polluted' days in a year was contributed by regional air pollutions; whereas 60% of which was from Hong Kong. 60%
40%
Alexis et al., 2009
HONG KONG IS RESPONSIBLE FOR 40% OF THE TOTAL 'POLLUTED DAYS' IN A YEAR!
However, accounting the much higher pollutant concentration from the Greater China, SOURCE APPORTIONMENT analysis showed that regional air pollutions actually contributed 60% of the total pollution in Hong Kong among those 'polluted' days in a year. Haven't said that, the rest of the air pollution (i.e. 40%) was generated locally, and thus Hong Kong has the full liability and own control to clean that up!