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Emissions from an international airport increase particle number concentrations 4-fold at 10 km downwind.

Hudda N, Gould T, Hartin K, Larson TV, Fruin SA - Environ. Sci. Technol. (2014)

Bottom Line: The total freeway length in Los Angeles is 1500 km.These results suggest that airport emissions are a major source of PN in Los Angeles that are of the same general magnitude as the entire urban freeway network.They also indicate that the air quality impact areas of major airports may have been seriously underestimated.

View Article: PubMed Central - PubMed

Affiliation: Keck School of Medicine, Department of Preventive Medicine, University of Southern California , Los Angeles, California 90089, United States.

ABSTRACT
We measured the spatial pattern of particle number (PN) concentrations downwind from the Los Angeles International Airport (LAX) with an instrumented vehicle that enabled us to cover larger areas than allowed by traditional stationary measurements. LAX emissions adversely impacted air quality much farther than reported in previous airport studies. We measured at least a 2-fold increase in PN concentrations over unimpacted baseline PN concentrations during most hours of the day in an area of about 60 km(2) that extended to 16 km (10 miles) downwind and a 4- to 5-fold increase to 8-10 km (5-6 miles) downwind. Locations of maximum PN concentrations were aligned to eastern, downwind jet trajectories during prevailing westerly winds and to 8 km downwind concentrations exceeded 75 000 particles/cm(3), more than the average freeway PN concentration in Los Angeles. During infrequent northerly winds, the impact area remained large but shifted to south of the airport. The freeway length that would cause an impact equivalent to that measured in this study (i.e., PN concentration increases weighted by the area impacted) was estimated to be 280-790 km. The total freeway length in Los Angeles is 1500 km. These results suggest that airport emissions are a major source of PN in Los Angeles that are of the same general magnitude as the entire urban freeway network. They also indicate that the air quality impact areas of major airports may have been seriously underestimated.

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Spatial pattern of simultaneously measured pollutantsduring 1400–1530on June 27, 2013. Concentrations are classified and colored by deciles.Panels (a)–(c) show data measured by the UW MMP and (d)–(f)show data measured by the USC MMP.
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fig5: Spatial pattern of simultaneously measured pollutantsduring 1400–1530on June 27, 2013. Concentrations are classified and colored by deciles.Panels (a)–(c) show data measured by the UW MMP and (d)–(f)show data measured by the USC MMP.

Mentions: Over large areas downwind of LAX,concentrations of pollutants other than PN were also elevated. Figure 5(a)–(c) show nearly indistinguishable spatialpatterns for PN, BC, and NO2 concentration measured simultaneouslyat distances of 9.5–12 km from LAX. This suggests a commonsource for these pollutants, although the BC concentration increaseswere not large when compared to PN and NOx, about 0.5–1 μg/m3 at 8–10 km downwind.While jet aircraft are not known to produce large amounts of BC, twostudies found elevated BC from plane takeoffs at LAX. Zhu et al. 20119 measured an increase of about 1 μg/m3 of BC due to plane activity 140 m downwind of the runway.Westerdahl et al. 20088 measured increasesin BC concentration of several μg/m3 during takeoffevents near the eastern LAX boundary, but also observed elevated BCconcentrations at all times. At a smaller airport, Dodson et al. 20094 found median contributions of about 0.1 μg/m3, about one-quarter of total BC measured at five sites rangingin downwind distance from 0.3−3.7 km, and also observed departuresproducing about twice the impact as arrivals. Therefore, it appearssome jets at LAX are capable of producing measurable increases inBC, particularly at takeoffs.


Emissions from an international airport increase particle number concentrations 4-fold at 10 km downwind.

Hudda N, Gould T, Hartin K, Larson TV, Fruin SA - Environ. Sci. Technol. (2014)

Spatial pattern of simultaneously measured pollutantsduring 1400–1530on June 27, 2013. Concentrations are classified and colored by deciles.Panels (a)–(c) show data measured by the UW MMP and (d)–(f)show data measured by the USC MMP.
© Copyright Policy - editor-choice
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4215878&req=5

fig5: Spatial pattern of simultaneously measured pollutantsduring 1400–1530on June 27, 2013. Concentrations are classified and colored by deciles.Panels (a)–(c) show data measured by the UW MMP and (d)–(f)show data measured by the USC MMP.
Mentions: Over large areas downwind of LAX,concentrations of pollutants other than PN were also elevated. Figure 5(a)–(c) show nearly indistinguishable spatialpatterns for PN, BC, and NO2 concentration measured simultaneouslyat distances of 9.5–12 km from LAX. This suggests a commonsource for these pollutants, although the BC concentration increaseswere not large when compared to PN and NOx, about 0.5–1 μg/m3 at 8–10 km downwind.While jet aircraft are not known to produce large amounts of BC, twostudies found elevated BC from plane takeoffs at LAX. Zhu et al. 20119 measured an increase of about 1 μg/m3 of BC due to plane activity 140 m downwind of the runway.Westerdahl et al. 20088 measured increasesin BC concentration of several μg/m3 during takeoffevents near the eastern LAX boundary, but also observed elevated BCconcentrations at all times. At a smaller airport, Dodson et al. 20094 found median contributions of about 0.1 μg/m3, about one-quarter of total BC measured at five sites rangingin downwind distance from 0.3−3.7 km, and also observed departuresproducing about twice the impact as arrivals. Therefore, it appearssome jets at LAX are capable of producing measurable increases inBC, particularly at takeoffs.

Bottom Line: The total freeway length in Los Angeles is 1500 km.These results suggest that airport emissions are a major source of PN in Los Angeles that are of the same general magnitude as the entire urban freeway network.They also indicate that the air quality impact areas of major airports may have been seriously underestimated.

View Article: PubMed Central - PubMed

Affiliation: Keck School of Medicine, Department of Preventive Medicine, University of Southern California , Los Angeles, California 90089, United States.

ABSTRACT
We measured the spatial pattern of particle number (PN) concentrations downwind from the Los Angeles International Airport (LAX) with an instrumented vehicle that enabled us to cover larger areas than allowed by traditional stationary measurements. LAX emissions adversely impacted air quality much farther than reported in previous airport studies. We measured at least a 2-fold increase in PN concentrations over unimpacted baseline PN concentrations during most hours of the day in an area of about 60 km(2) that extended to 16 km (10 miles) downwind and a 4- to 5-fold increase to 8-10 km (5-6 miles) downwind. Locations of maximum PN concentrations were aligned to eastern, downwind jet trajectories during prevailing westerly winds and to 8 km downwind concentrations exceeded 75 000 particles/cm(3), more than the average freeway PN concentration in Los Angeles. During infrequent northerly winds, the impact area remained large but shifted to south of the airport. The freeway length that would cause an impact equivalent to that measured in this study (i.e., PN concentration increases weighted by the area impacted) was estimated to be 280-790 km. The total freeway length in Los Angeles is 1500 km. These results suggest that airport emissions are a major source of PN in Los Angeles that are of the same general magnitude as the entire urban freeway network. They also indicate that the air quality impact areas of major airports may have been seriously underestimated.

Show MeSH
Related in: MedlinePlus