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ITCT 2K2 Field Study (Intercontinental Transport and Chemical Transformation). http://www.al.noaa.gov/WWWHD/pubdocs/ITCT/2k2/. David Parrish, NOAA Aeronomy Laboratory & ITCT 2K2 Science Team. Today (briefly):. • ITCT 2K2 Introduction. • Examine a major Asian emission transport event to
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ITCT 2K2 Field Study (Intercontinental Transport and Chemical Transformation) http://www.al.noaa.gov/WWWHD/pubdocs/ITCT/2k2/ David Parrish, NOAA Aeronomy Laboratory & ITCT 2K2 Science Team Today (briefly): • ITCT 2K2 Introduction • Examine a major Asian emission transport event to demonstrate utility of data set. • Is there a temporal trend in springtime tropospheric ozone in the Eastern Pacific?
PHOBEA-2 Trinidad Head Ground Site PHOBEA-2 - Jaffe et al. • ITCT 2K2 Field Study • Spring 2002 • West Coast of North America 13 Flights of NOAA WP-3D April 22 - May 19 Goal: Characterize chemical composition of the air masses coming ashore, focus on ozone and aerosols. Coordnated with PEACE-B (Japanese aircraft study)
NOAA WP-3D Flight5/5/2002122 - 125 deg West C. Forster and A. StohlTechnical University of MunichCO tracers FLEXPART Forecast5/5/2002125 deg West
NOx, NOy Measurements:T. Ryerson et al. Up to about 1 ppbv NOy transported with CO NOAA WP-3D Flight5/5/2002122 - 125 deg west
HNO3Measurements:Chemical Ionization MassSpectrometerA. Neuman et al. Most of the HNO3 has been removed; PAN dominates NOAA WP-3D Flight5/5/2002122 - 125 deg west
O3 elevation is moderate and variable; poor correlation with CO NOAA WP-3D Flight5/5/2002122 - 125 deg west Altitude (km)
CH3CN Measurements:Proton Transfer MassSpectrometerJ. de Gouw et al. Largest biomass influence at high altitudes NOAA WP-3D Flight5/5/2002122 - 125 deg west Altitude (km)
Particle Size Distributions:C. Brock et al. Particle Number high at high CO NOAA WP-3D Flight5/5/2002122 - 125 deg west Altitude (km)
Particle Size Distributions:C. Brock et al. Altitude (km) Particle Volume high at lower altitudes
Single Particle MassSpectrometer MeasurementsD. Murphy et al. Mineral Aerosol in distinct layers NOAA WP-3D Flight5/5/2002122 - 125 deg west
Emissions of O3 precursors from Asia have increased Streets et al. Have O3 levels in the Eastern Pacific changed? Let’s look back in time
ITCT 2K2 Lassen Volcanic National Park 41.6 deg N 1756 m (Mar - May) O3 levels in the Eastern Pacific have increased in the last 2 decades Jaffe et al. slope = 0.84 ppbv/yr r2 = 0.52 (O3 < 100 ppbv, CO < 150 ppbv, ralt > 2 km over or near continent, 4/20-5/11)
O3 levels in the Eastern Pacific have increased in the last 2 decades
ITCT 2K2 Field Study (Intercontinental Transport and Chemical Transformation) http://www.al.noaa.gov/WWWHD/pubdocs/ITCT/2k2/ • Introduced ITCT 2K2 • Pronounced episodes of Intercontinental Transport of emissions clearly observed. • Measurements will allow us to characterize chemical and physical properties of gaseous and aerosol species. • Substantial evidence for ≈ 0.5 ppbv/yr increase of tropospheric O3 in the Eastern Pacific