## 1 Introduction
### Maritime Emissions and Their Effects
#### 1.1.4 Italian Ports
The importance of maritime BC emissions has been noted in many studies of Italian ports [43; 44; 45; 46; 47; 48; 49; 50; 51; 52; 53; 54]. One is a case study of Civitavecchia, which is the port for Rome [45]. It distinguishes among three levels of measurement of particulate matter: PM\({}_{10}\), PM\({}_{2.5}\) and black carbon, which is PM\({}_{1}\). The distinction is important for policymaking because PM\({}_{10}\) and PM\({}_{2.5}\) are covered by current EU and local regulations. However, maritime black carbon is not explicitly covered by regulations even though it is a serious health threat and a significant component of ships' air polluting emissions. An implication is that studies of ships' emissions need to be explicit about the types of emissions that are and are not included \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**Port**} & **Number** & **No. of** & **Port Call** & **Port Call** & **(PM\({}_{10}\)) a** & **(PM\({}_{10}\)) a** & **NOx** & **NOx** \\  & **of Ships** & **Ships** & **Time** & **Time** & **(kg)** & **(Rank)** & **(kg)** & **(kg)** & **(Rank)** \\ \hline Cagliari & 45 & 5–6 & 2592 & 7 & 1468 & 9 & 144,070 & 7 \\ Civitavecchia & 76 & 1 & 5466 & 2 & 8898 & 2 & 500,326 & 2 \\ Genoa & 31 & 9 & 3376 & 4 & 4946 & 5 & 261,550 & 5 \\ La Spezia & 43 & 6 & 3278 & 5 & 3721 & 6 & 194,646 & 6 \\ Livorno & 63 & 3 & 4720 & 3 & 6497 & 3 & 378,129 & 3 \\ Messina & 45 & 5–6 & 2296 & 9 & 2296 & 8 & 130,777 & 8 \\ Napoli & 52 & 4 & 2968 & 6 & 5138 & 4 & 303,708 & 4 \\ Palermo & 33 & 8 & 2393 & 8 & 2393 & 7 & 130,054 & 9 \\ Venice & 68 & 2 & 7988 & 1 & 10,961 c & 1 & 600,337 & 1 \\ Total & [456 b] & 35,077 & & 46,318 & & 2,643,597 & \\ \hline \hline \end{tabular}  
* BC included in PM\({}_{10}\). b Includes multiple visits. c 3 rd highest in Europe.  
\end{table} 
Table 4: Cruise Ship Emissions. \begin{table}
\begin{tabular}{c c c c c} \hline \hline  & **Number of** & & & **Percent** & **Rank among** \\
**Port** & **Passengers** & **Change from 2018 to 2019** & **Number of** & **Change from 2018 to 2019** & **Moditerranean** \\  & **(2019)** & & & **Ports** \\ \hline Civitavecchia & 2.56 & +4.9 & 827 & +8.8 & 2 nd \\ Venice & 1.55 & [’stable’] & 500 & [’stable’] & 5 th \\ Genoa & 1.35 & +33.5 & 268 & +17.0 & 6 th \\ Napoli & 1.23 & +14.6 & 456 & +20.3 & 7 th \\ \hline \hline \end{tabular}  
* BC included in PM\({}_{10}\). b Includes multiple visits. c 3 rd highest in Europe.  
\end{table} 
Table 3: Cruise Port Activity in Italy’s Top Four Cruise Ports. in the study and in detailed discussions of the results and implications. (See the Annex for additional definitional and measurement issues.) In Table 4, in terms of the volume of cruise ship emissions, Venice was not only first in Italy, it was third among all European countries [55]. Some other Italian ports, such as Messina, were ranked relatively high in the number of ships but not in their time in port or their emissions. Genoa, on the other hand, ranked low in the number of ships but high in time in port and their emissions. In sum, Italian port emission levels of PM (including black carbon), as well as sulfur dioxide and nitrogen oxides, are relatively high compared with other large European ports. They are high in absolute terms, such as total tons per year, and also high in relative terms, such as tons per vessel-visit. The emissions are particularly high for cruise ships, but they are also high for container ships and other kinds of vessels. On the other hand, there are also ports elsewhere in Europe with higher levels of air pollutants by several measures.