## 2 Emission Sources at Seaports
Scope 2 accounts for the indirect GHG emissions from the generation of the purchased energy consumed by the reporting company, e.g., the emissions occurring at the facilities where the purchased \begin{table}
\begin{tabular}{l l} \hline \hline
**Emission Source Type** & **Specific Emission Sources** \\ \hline Mobile type & Seagoing vessels; support vessels; cargo handling equipment; heavy-duty vehicles; light-duty vehicles; locomotives \\ \hline \multirow{3}{*}{Stationary type} & Offices; warehouse; storage facilities; quayside, gate, rail terminal facilities; electrical grid facility; electric charging \\  & facilities; buildings; parking spaces; manufacturing, industrial, power plants; lighting; maintenance facilities; \\ \cline{1-1}  & heating ventilation and air conditioning \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Seaport emission source categorisation from a functionality perspective (based on [10]). \begin{table}
\begin{tabular}{l l l} \hline \hline
**Source Category** & **CO\({}_{2}\)e in 2006** & **CO\({}_{2}\)e in 2021** \\ \hline Cargo handling equipment & 154,184 (23.78\%) & 166,170 (20.16\%) \\ Heavy-duty trucks & 224,050 (34.56\%) & 403,806 (48.99\%) \\ Rail locomotives & 14,710 (2.27\%) & 27,691 (3.36\%) \\ Ocean-going vessels & 221,638 (34.19\%) & 191,104 (23.19\%) \\ Harbour craft & 33,703 (5.20\%) & 35,475 (4.3\%) \\ \hline Total & 648,284 (100\%) & 824,245 (100\%) \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Port GHG emissions by source category (tonnes/year) in 2006–2021 in Port of New York and New Jersey (based on [11]). electricity is generated. The definitions of scopes 1 and 2 ensure that the GHG emissions will not be double-counted in the same scope. Scope 3 accounts for all other indirect emissions that occur in the value chains of the reporting company, e.g., leased assets, employee commuting, business travel, waste generated in operations, upstream activities (such as extraction and production of purchased materials, transportation and distribution of purchased products, fuel, and energy-related activities), and downstream activities (such as transport and distribution of sold products, processing of sold products, use of sold products and services, end-of-life treatment of sold products) [12]. The classification of three GHG emission scopes provides a useful view on which emission sources are under the control of the reporting company and which emission sources are not directly controllable but may be influenced. In the context of seaports, the GHG emission sources could be mapped into three scopes, as shown in Table 3.  
A couple of points are worth noting. Firstly, seaports could involve a wide range of different stakeholders and different seaports have different geographical and operational boundaries, which makes it very difficult for the seaport to influence the scope 3 emission sources. The classification of the emission sources in Table 3 is more suitable for operating ports (where the port authority owns and operates the maritime terminal facilities and equipment, or a terminal operator leases the land and develops and operates the port). It requires some adjustments to the scope 1 and 2 emission sources for landlord ports (where the port authority owns the port and terminal operators operate the port facilities). Secondly, the assessment of the emission inventories in seaports may be extended to some hinterland sources such as roadways, freeways, highways, urban residential areas, factories, and service facilities. In particular, from the system perspective, the port may act as an energy hub that connects to offshore windfarms at sea and supplies energy to hinterland industrial sectors. The implication is that the scope 3 sources could be much broader, more complicated, and difficult to decarbonise. Naturally, a seaport has its geographical boundary.