 |
NARSTO Workshop on Innovative Methods for Emission Inventory Development and Evaluation University of Texas, Austin October 14-17, 2003 |
 |
Measurements of Marine Vessel Emissions
E.J. Williams1,2, B. Lerner1,2, A.M. Middlebrook1, J.F. Meagher1, and F.C. Fehsenfeld1,2
1 Aeronomy Laboratory/NOAA, Boulder, CO 80305
2 CIRES, University of Colorado, Boulder, CO 80309
Emission of oxidized nitrogen and sulfur compounds from large marine vessels constitutes a significant source of these species. For example, nitrogen from this source represents more than 14% of all combustion emissions globally (1). But these emissions are also important regionally in coastal areas and locally in ports since it has been estimated (1) that 70% of all ship emissions occur within 400 km of land. Currently, the best available inventory data are compiled from marine fuel usage and various emission factors. Sulfur emission factors are directly related to the sulfur content of fuel while nitrogen emission factors are primarily related to the engine type: slow-speed diesel, medium-speed diesel, and other (generally steam-turbine). The average emission factors used in inventories come from a Lloyd´s Register of Shipping sponsored emissions research program in which unmodified, in-service marine vessel emissions were measured directly at the stack. While the results from this program represent the best available data, the significance of marine vessel emissions suggests that additional evaluation of emission factors be conducted.
During the 2002 New England Air Quality Study (NEAQS 2002) the NOAA research vessel Ronald H. Brown was equipped with trace gas and aerosol monitoring instrumentation for the purpose of investigating the factors that affect air quality in coastal New England. As a part of that study, numerous opportunities arose to measure gaseous and particulate emissions from marine vessels, both in port and underway. This talk will present measurements from the NEAQS 2002 and relate those data to current inventory estimates of marine vessel emissions.
(1) Corbett, J.J., et al., Global nitrogen and sulfur inventories for oceangoing ships, J. Geophy. Res., 104, 3457-3470, 1999.