international aircraft operations, including passenger and freight
transport. In assessing GHG emissions along the built-up vehicle
supply chain from Korea, Nieuwenhuis et al. (2012) considered
emissions from rail, trucks, cars, and ships. Table 1 presents the
scope and key findings of these studies. It illustrates emission factors
ranging from 359 to 963.45 g CO2/tonne-km for air freight,
from 4.4 to 56.7 g CO2/tonne-km for sea, from 50 to 160.7 g CO2/
tonne-km for trucks, and from 10.4 to 22.7 g CO2/tonne-km for
trains, respectively. As expected, GHG emissions from air transport
are almost an order of magnitude higher than that of sea and land
transport.
2.2. Hong Kong as one of the world's logistics hubs
Hong Kong has one of the best deep-water ports in the world. It
is strategically located at the south-east coast of the Pearl River
Delta Region in which manufacturers in Guangdong province produce
a significant amount of goods for the world market. In addition
to its geographical advantage, Hong Kong is a free port, has a
simple tax system with a low tax rate, efficient customs,