Estimating greenhouse gas emissions from ships on four ports of Georgia from 2010 to 2018

This study is a comprehensive inventory of the greenhouse gas emissions from ships in the Georgian ports and aims to analyse the level of exhaust gas emissions in ports. Georgia has four main ports (the Poti Sea Port, the Batumi Port, the Port of Kulevi, and the Port of Supsa) which are a vital link in Georgia's economy and transfer point for handling oil and oil products. The ship activity-based method is used to calculate the emissions of NOX, CO2, VOC, PM, and SO2 from ships between 2010 to 2018 years. The analysis is executed according to the type of ships (container, bulk dry, general cargo, tanker, chemical, liquified gas, and others) and operational modes (cruising, manoeuvring, and hoteling). The total emissions from ports are 54.640, 44.030, 11.910, and 9.206 tonnes per year for Batumi, Poti, Kulevi, and Supsa, respectively. The study indicates that the Batumi Port is the main source of atmospheric pollution in the region followed by the Poti Sea Port. Tanker, general cargo, and container ships are the main polluters at all ports and emit almost 82% of all emissions in the Georgian ports. The greenhouse gas emissions emitted from vessels during the mode of cruising were 82% of the total amount; manoeuvring emissions were 5% and hoteling 13% in operational modes. The environmental costs of ports can reach to (sic)19.1 million or (sic)14.288 per ship call in 2018. The uncertainties of the pollutant emission estimates were measured, with lower bounds of - 12.3 to - 33.9% and upper bound of 10.8 to 30.0% at 95% confidence intervals. The lower uncertainties in the study emphasised the importance of the ship activity-based method in improving ship emission estimates.