Airborne and Shipboard Measurements of Aerosol Particle Size Distributions in Ship Plumes at Baltic Sea

JAN HOVORKA, Pavel Paces, Dominik Smok, Sandra Pier, Thomas Gröger, Helena Osterholz, Charles University

     Abstract Number: 470
     Working Group: Combustion

Abstract
Ship emissions significantly contribute to global particulate mass. About 15% of the world’s cargo traffic occurs at the Baltic Sea. To better predict the fate of plumes there, we evaluate ship plume dispersion at scale of hundred meters from ships.

Aerosol size distributions were measured by a miniaturized scanning electrical mobility sizer positioned at unmanned airship or on board of a working boat. Airborne measurements at heights about 70 m at the distance more than 200 meters from the ship revealed count median diameter of plume aerosol at 65 nm or 120 nm and concentrations reaching 10⁵ per cubic centimeter. In contrast, plume aerosol measurements conducted on board of a working boat at the distance about 50 meters and more and at height 1.5 meter above sea surface revealed CMD at 20 nm. Fast coagulation with sea aerosol particles or droplets would be plausible explanation of those nanoparticle absence at higher heights which also suggests their limited transport from the cargo ships.

Supported by the Czech Science Foundation (22-03426L) and German Research Foundation (471841824).