Transcript Transpacific transport of anthropogenic aerosols and

Predicted change in global secondary organic
aerosol concentrations in response to future
climate, emissions, and land-use change
Colette L. Heald
NOAA Climate and Global Change Postdoctoral Fellow
University of California, Berkeley
([email protected])
Daven Henze, Larry Horowitz, Johannes Feddema, Jean-Francois
Lamarque, Alex Guenther, Peter Hess, Francis Vitt, Allen Goldstein, Inez
Fung, John Seinfeld
International Union of Geodesy and Geophysics
July 9, 2007
ORGANIC CARBON AEROSOL
SemiVolatiles
Partitioning (non-linear)
Secondary
Organic
Aerosol
Primary
Organic
Aerosol
Oxidation
by OH, O3, NO3
Isoprene
Monoterpenes
Sesquiterpenes
Aromatics
Direct
Emission
Fossil Fuel
BIOGENIC SOURCES
Biomass
Burning
ANTHROPOGENIC SOURCES
WHY WE SHOULDN’T FOCUS EXCLUSIVELY ON SULFATE…
Sulfate
Organics
[Zhang et al., in press]
Organic carbon aerosol is the green part of the pie  globally more than sulfate
MODELING FRAMEWORK
Community Land Model (CLM3)
Datasets: Lawrence and Chase [2007]
Feddema et al. [2007]
LAI (MODIS)
Plant Functional Types
Soil moisture
Vegetation Temperature
BVOC Algorithms
Vegetation
Meteorology [Guenther et al., 1995; 2006]
Monterpenes: GEIA
Isoprene: MEGAN
BVOC Emissions
Radiation
Precipitation
Community Atmospheric Model
(CAM3)
Anthropogenic
Emissions,
GHG concentrations,
SST
Chemistry
Transport
Radiation
SOA production
2-product model from
oxidation of:
1. Monoterpenes
[Chung and Seinfeld, 2002]
2. Isoprene
[Henze and Seinfeld, 2006]
3. Aromatics
[Henze et al., 2007]
PRESENT-DAY (2000) SOA
Isoprene is the largest SOA source in this simulation, and also the
longest lived  dominates burden
PRESENT/PROJECTED BIOGENIC EMISSIONS
496 TgC/yr
43 TgC/yr
2100:
607 TgC/yr
2100:
51 TgC/yr
22% increase primarily driven by global temperature increases (1.8°C)
PRESENT/PROJECTED ANTHROPOGENIC EMISSIONS
45 TgC/yr
2100:
A1B: 72 TgC/yr
A2: 96 TgC/yr
16 TgC/yr
2100:
A1B: 20 TgC/yr
A2: 35 TgC/yr
Large increases predicted, especially over Asia
CHANGES IN TOTAL SOA CONCENTRATIONS IN 2100
(A1B) FROM PRESENT-DAY
Δ Anthropogenic
Emissions
Δ Biogenic
Emissions
Δ Climate
Surface SOA
Zonal SOA
Global Burden
+7%
+26%
+6%
CHANGES IN SOA CONCENTRATIONS IN 2100 FROM
PRESENT-DAY DUE TO LAND-USE CHANGE (A2)
Feddema et al. [2007] Projections
BVOC emissions
SOA (TOTAL)
Isoprene
Monoterpenes
Expansion of croplands (low BVOC emitters) at the expense of broadleaf trees
OVERALL SOA BURDEN: -14%
TOTAL EFFECT OF EMISSIONS & CLIMATE ON SOA
TOTAL SOA
Climate and Emission: +36%
Anthropogenic Land-use: -14%
Natural Vegetation: ??
SOA SENSITIVITY SIMULATIONS:
REGIONAL SOA SOURCES
South America is the
largest SOA source in
present-day but significant
growth expected for Asia
by 2100 (and may overtake
South America as the
largest SOA source region
under an A2 scenario).
CHANGES TO SOA PRODUCTION EFFICIENCY
SOA production is less efficient under high NOx conditions.
2000
2100-2000
Surface
NO/HO2
SOA production efficiency likely increase in EU and NA due to NOx ↓
but will decrease in urban regions of SH/tropics.
INCREASING SOA: CLIMATE IMPLICATIONS?
SULFATE
SOA
Present-Day Burden: 0.59 TgC
Projection: 36%↑
SOA Burden
Present-Day Burden: 0.5-0.7 TgS1
Projection:↓ by > 50% by 2100?
Andreae et al. [2005] suggest ↓ sulfate will accelerate greenhouse gas
warming, but SOA may compensate
1 [Koch et al., 1999; Barth et al., 2000; Takemura et al., 2000]