Aircraft hydrocarbon emissions at Oakland International Airport.
To help airports improve emission inventory data, speciated hydrocarbon emission indices have been measured from in-use commercial, airfreight, and general aviation aircraft at Oakland International Airport. The compounds reported here include formaldehyde, acetaldehyde, ethene, propene, and benzene. At idle, the magnitude of hydrocarbon emission indices was variable and reflected differences in engine technology, actual throttle setting, and ambient temperature. Scaling the measured emission indices to the simultaneously measured formaldehyde (HCHO) emission index eliminated most of the observed variability. This result supports a uniform hydrocarbon emissions profile across engine types when the engine is operating near idle, which can greatly simplify how speciated hydrocarbons are handled in emission inventories. The magnitude of the measured hydrocarbon emission index observed in these measurements (ambient temperature range 12-22 degrees C) is a factor of 1.5-2.2 times larger than the certification benchmarks. Using estimates of operational fuel flow rates at idle, this analysis suggests that current emission inventories at the temperatures encountered at this airport underestimate hydrocarbon emissions from the idle phase of operation by 16-45%.
Herndon
Scott C
SC
Aerodyne Research, Inc., Billerica, Massachusetts, USA. herndon@aerodyne.com
Wood
Ezra C
EC
Northway
Megan J
MJ
Miake-Lye
Richard
R
Thornhill
Lee
L
Beyersdorf
Andreas
A
Anderson
Bruce E
BE
Dowlin
Renee
R
Dodds
Willard
W
Knighton
W Berk
WB
D000393:Air Pollutants / Q000737:chemistry*; D000397:Air Pollution / Q000517:prevention & control; D000401:Aircraft; D002140:California; D006838:Hydrocarbons / Q000737:chemistry; D010578:Petroleum / Q000032:analysis; D001335:Vehicle Emissions / Q000032:analysis*
D000393:Air Pollutants; D006838:Hydrocarbons; D010578:Petroleum; D001335:Vehicle Emissions