# Impact of Disruption on Ship Emissions in Port: Case of Pandemic in Long Beach
## 4 Experiment and Analysis
### Emissions from Ship Quantity and Different Types  
The spread of COVID-19 in early 2020 had a devastating impact on all industries. Capacity decreases as the number of workers reduces across all industries. The reduction in cargo volume has also led to a decrease in the number of vessels arriving in port. Analysing AIS data (Figure 3) illustrates the quantity of ship arrivals in the POLB. The number of incoming ships was around 2100 in 2019, and 1850 in 2020, which was only 88% of the  
Figure 2: Port of Long Beach Structure Map.  
\begin{table}
\begin{tabular}{c c} \hline \hline \multirow{2}{*}{**Year**} & **Shore Power Regulation** \\  & **(\% of Fleet’s Visits to Each California Port)** \\ \hline
2014–2016 & 50\% \\
2017–2019 & 70\% \\
2020+ & 80\% \\ \hline \hline \end{tabular}
\end{table}
Table 5: California port shore power regulation for different years.  
number in 2019. In 2021, the number of ship arrivals has improved slightly, but has still not fully recovered to pre-COVID pandemic conditions.  
As can be seen from the figure, the most significant decline in the cruise industry is likely to be caused by the fact that people have reduced travel plans due to the COVID pandemic. The number of tankers decreased from approximately 410 in 2019 to less than 370 in 2020. The dip in tanker numbers can be related to a decline in people's travel due to the COVID pandemic, which has induced a decrease in demand for fuel. In addition, the COVID pandemic has reduced capacity in the oil industry, reducing tanker demand.  
The characteristics of ship emissions are analysed in terms of ship type. In this paper, ship types are divided into five main categories: bulk, container, cruise, tanker, and others. Figure 4 depicts CO\({}_{2}\), NO\({}_{\chi}\), SO\({}_{\chi}\), CO, PM2.5, and PM10 emissions from different types of ships at the POLB from 2019 to 2021. According to the calculation, the 2020 emissions are lower than the 2019 emissions for the same period. In 2019, the yearly CO\({}_{2}\) pollution of ships in the POLB zone was around 300,038 million tonnes; in 2020, it was roughly 286,037 million tonnes. The tanker emitted about 135,294 million tonnes of carbon dioxide in 2019, followed by the container ship with 94,219 million tonnes. In the two years between 2019 and 2020, container ship emissions increased dramatically, which is also directly tied to the increase in container ship numbers. According to the POLB data, there were 763,038 TEUs in 2019, while there were 8,113,318 TEUs in 2020, a 6.3% rise. The increase in container throughput correlates with an increase in container ships arriving at the POLB. According to the AIS data, as described in Section 4.1 of this study, there is a modest rise in the quantity of container ships. However, the rise in container ships entering the POLB region is insufficient to account for the massive increase in CO\({}_{2}\) emissions. Therefore, the increase in CO\({}_{2}\) pollution in 2020 was primarily attributable to the long anchoring period of container ships in the POLB area, partly attributable to the drop in productivity induced by the drop in the amount of port personnel, generating congestion in the port. In 2021, the POLB sees further increases in congestion, and a significant increase in the amount of various pollutants emitted, with the largest increase in emissions from container ships. The near-doubling of the increase, but the slight decrease in the number of vessels, shows that most vessels are forced to stay longer, due to the decrease in port processing speed.  
Figure 3: Quantity of different ship types arriving at the POLB.