NO 3 + VOCs
description
Transcript of NO 3 + VOCs
BSOA workshopAugust 2008
NOx-mediated Chemistry - Climate Interactions via Atmospheric Aerosols
Julie Fry, currently unemployed!(was UC Berkeley, starting at Reed College next week)
NO3 + VOCs
RONO2
aerosol
NOx Climate effects?
NO + oxyRO2
RONO2(g)
-Chamber studies of SOA formation-AMS organic nitrate standard studies-Modeling regional importance of NOx-mediated SOA formation-Future: Measuring aerosol chemical composition with Hi-Vol samplers &
offline GC-MS, FTIR, NMR; regional modeling (WRF-Chem)
BSOA workshop
March 13, 2008
NO3 in Juelich SAPHIR chamber, June 2007
NO3 TD-LIF
NO
2 TD
-LIF
inlets
BSOA workshop
o N2O5 +NO3
+ β-pineneΔ aerosol
DRY
60% RH
Y~50%
Y~50%
aerosol formation
HC
MY aero
BSOA workshop
Absorptive partitioning model requires Pvap = 4x10-6 Torr
O2NO OH
estimated Pvap~6x10-4 Torr
Modeling nitrate partitioning
BSOA workshop
Modeling NO3 + β-pinene
Yield(Alkyl nitrates) = 30%
BSOA workshop
How much aerosol could NO3 + β-pinene make globally?
• Mass yield of aerosol from NO3 + β-pinene: ~50%
• Global annual β-pinene emissions: ~ 33 Tg yr-1
• Fraction of β-pinene that reacts with NO3, based on relative NO3, O3, and OH lifetimes: ~ 30%
→ .3 x .5 x 33 Tg yr-1 = 5 Tg yr-1
SOA source estimates: Kanakidou et al, 2005: 12 – 70 Tg year-1
Goldstein & Galbally, 2007: 510 – 910 Tg year-1