PM2.5 Co-benefits of Climate Change Legislation Part 1: California’s AB 32
Christina Zapata1, Nicholas Muller2, and Michael J. Kleeman1*
1
Department of Civil and Environmental Engineering, University of California, Davis. 1 Shields Avenue,
Davis CA 95616. 2Department of Economics, Environmental Studies Program, Middlebury College,
Middlebury VT 05770.
*Corresponding author. Tel.: +1 530 752 8386; fax; +1 530 752 7872. E-mail address:
mjkleeman@ucdavis.edu (M.J. Kleeman).
Reference Acronyms:
CARB – California Air Resources Board
CEC – California Energy Commission
FRA – Federal Railroad Administration
CDWR – California Department of Water Resources
SWRCB - State Water Resources Control Board
S.1. Emission Changes from Individual AB 32 Measures
Table S1 summarizes the business as usual (BAU) emissions and Table S2 summarizes changes to
emissions for source categories impacted by AB 32 control measures. The “Levels” defined in the
current study were designed to inform the reader about which economic sectors provided the greatest
benefits from AB 32 emissions changes. The individual measures assigned to each “Level” are taken
directly from AB 32. Supplemental information sources were used to determine thresholds for source
inclusion in various AB 32 measures when these thresholds were not directly provided by AB 32. In
cases where supplemental information was not available or the resulting thresholds seemed impractical,
we provided our own expert opinion. Table S1 only summarizes information for the emission sources
that are influenced by AB 32 measures. Table 2 in the main text provides insight about the magnitude of
the emissions change for the entire sector.
The Public Health and Environmental Benefits Analysis for AB 32 (CARB 2008) estimated changes in NOx
and PM2.5 emissions for a variety of mobile and stationary sources. In the present study, the same
fraction of emission reduction (or increase) was applied to TOG, NMOG, CO, SOx, and/or NH3 if those
emissions were non-zero in the BAU inventory. Emissions from sources in the petroleum industry were
scaled based on controls applied to methane or hydrocarbon emissions.
Level 1: Industrial Measures
BAU emissions from industrial sources include emissions from on-site electricity generation at a major
facility that is used directly at that same facility. The energy efficiency measures applied under Level 1
were assumed to reduce demand for electrical power in this sector. Roughly 70 major industrial facilities
including refineries, cement plants, high emitting oil and gas extraction plants, hydrogen plants, and
mineral plants were affected by the energy efficiency measures in Level 1 controls. See discussion in the
main text for further details.
Level 2: Commercial and Institutional Electricity Generation Measures
The effect of AB 32 measures related to commercial electricity consumption/generation were summed
and the net change in electrical generation was then applied using the following priority: reductions in
electrical generation were applied first to out-of-state fossil fuel electricity generation, and then to instate fossil fuel electricity generation as described in the main text. For the Renewable Electricity
Standard, “electricity generation from other” includes the increase in emissions associated fossil-fueled
boilers and heaters attached to solar thermal electrical generation units. Many solar thermal power
plants have boilers and heaters that assist in the startup phase of the plant and that provide protection
against freezing of the working fluids. The Green Buildings measure was applied to new and existing
state, residential, and commercial buildings (including schools). It was assumed that the adoption of
energy efficient building standards and the use of more energy efficient appliances would decrease
emissions associated with electricity and natural gas consumption in buildings.
Estimates for reduced energy consumption associated with water use were obtained from multiple
sources. A 20% improvement in “end use” water efficiency was assumed to reduce electricity demand
for end use water supplies and wastewater treatment by a proportional amount (CEC Nov 2005, CEC
2009a, Pacific Institute Sep 2005). Utilization of urban runoff, water recycling, and improvements to
water system energy efficiency were assumed to reduce electrical consumption for water treatment by
a further 10% (CEC Nov 2005, CEC 2009a, CDWR Jun 2003, SWRCB Mar 2008 NRDC Aug 2009). The
projected net effect of all water-related measures in 2030 is a 5% reduction in total electricity
consumption in California.
Level 3: Agriculture Measures
AB 32 stipulates an increase in electricity generation from renewable sources. Central California and
southern California have large dairy farms that produce methane gas through the decomposition of
dairy waste. The installation of combustion systems to produce electricity from this methane source
satisfies the definition of renewable energy production. Large dairies were not explicitly defined by AB
32, but EPA provides a definition for a large dairy as ≥500 dairy cows per facility (Ed. K.F. Roos 2004).
Over 1000 dairy farms in California have ≥500 dairy cows, accounting for over 90% (1.67 million) of all
CA dairy cows in 2007 (USDA 2009). Implementing biogas digesters on each of these facilities would
require an investment of ~$2B, which seemed prohibitively expensive. The current study assumes that
the largest dairy facilities emitting ≥5100 kg/hr of TOG would install biogas digesters (<20 dairies in total
meet this criterion) as a more practical threshold for implementation.
Level 4 and Level 5: On-road and Other Mobile Transportation Measures
The Low Carbon Fuel Standard specifies emission reductions for advanced passenger vehicles and
increases in emissions for transport of biofuel feedstock via rail and heavy duty trucks. All on-road
vehicles using biofuels were assumed to have reduced tailpipe emissions factors. The measures
associated with Port Drayage Trucks regulation were applied within an 80 mile radius from the 6 ports
mentioned in the main text based on survey results describing the average distance traveled by trucks
servicing the ports. High Speed Rail emissions were based on the HST Investment-grade scenario
analysis (FRA Aug 2005). Investment-grade ridership forecasts were used to approximate the potential
VMT reductions from 26.6 million annual trips from highway travel and 15.4 million trips for air travel.
Regional transportation related greenhouse gas targets were assumed to apply to gasoline vehicles.
Brake wear and road dust was included in the BAU emissions totals for on-road gasoline vehicles and
these emissions were not scaled by AB 32 measures. The goods movement statewide efficiency
improvements were assumed to apply to diesel vehicles, the same source assumed in the CARB Sep
2008 reference. Clean/Green ship measures were assumed to apply equally to all ships including
commercial and ocean-going vessels during all modes of operation (maneuvering, berthing, and intransit). Industrial off-road equipment excludes construction and farming equipment.
S.2. Impact of AB 32 on PM2.5 Component Concentrations
Figures S1 through S4 illustrate the effect of AB 32 defined Implementation Levels on PM2.5 component
concentrations including organic carbon (OC), elemental carbon (EC), sulfate (S(VI)), and nitrate (N(V)).
Implementation Level 2 produces the largest reduction in OC and EC concentrations but these large
changes are highly localized around the industrial emissions point source. The most widespread
reductions of OC and EC during the simulated winter stagnation event are produced by electric utility
and on-road mobile Implementation Levels 2 and 4, respectively, with OC concentrations reduced by
~0.3 µg m-3 over large portions of the state. Dairy biogas combustion for electricity generation increases
PM2.5 organic and elemental carbon concentrations by ~0.06 µg m-3 in the SJV. PM2.5 sulfate
concentrations are expected to decrease by ~1.49 µg m-3 in the port regions due to ship controls under
Implementation Level 5 and increase in the SJV by ~0.1 µg m-3 due to the combustion of dairy biogas
under Implementation Level 3. This agrees with the sulfur content of the fuel that will be combusted
less or more for those sources as specified by the measures. All AB 32 defined Implementation Levels
produce reductions in regional nitrate concentrations ranging from 0.17-0.3 µg m-3 with the exception of
Implementation Level 3 that increases nitrate concentrations in the SJV by 0.5 µg m-3. It is evident that
due to the diverse range of emission sources and rates for specific California regions as well as the
implementation of multiple GHG measures, each California region differs from one another in PM2.5
mass and composition concentration benefit or disbenefit.
Table S.1. Business as Usual emissions for sources impacted by AB 32 measures in tonnes per day.
Simulated
Sources
Level
Industrial Electricity Generation
Oil and Gas Production Equipment
1
Natural Gas Transmission
Petroleum Refining Flares
Petroleum Fugitive HC Pipeline Valves
Commercial and Governmental Waste Disposal
Electricity Generation from Coal
Electricity Generation from Distillate Oil
Electricity Generation from Coke
Electricity Generation from LPG
Electricity Generation from Jet Fuel
2
Electricity Generation from Diesel
Electricity Generation from Natural Gas
Electricity Generation from Geothermal
Electricity Generation from Landfill Gas
Electricity Generation from Other
Residential and Commercial Natural Gas
3
4
5
Dairy Manure Waste
On-Road Gasoline Vehicles
On-Road Diesel Vehicles
Transportation Refrigeration Units
Industrial Off-road Equipment
6
Commercial Harbor Craft
Ocean Going Vessels
Commercial Aircraft
Freight Trains
TOG
NMOG
CO
NOx
SOx
NH3
TSP
PM10
PM2.5
5.12E+01
2.60E+00
2.40E+02
9.27E+00
2.37E+00
6.66E+01
2.43E-02
3.70E-01
4.04E-01
5.82E-02
5.80E-04
4.10E-04
2.61E+01
1.37E+01
9.83E+00
7.64E-03
9.12E+00
1.04E+03
2.06E+02
1.51E+01
6.10E+00
8.04E+00
5.51E+00
3.04E+01
1.09E+01
1.46E+01
1.21E+01
1.32E+00
1.51E+01
7.08E+00
1.69E+00
1.15E+00
3.93E-03
3.42E-01
6.80E-02
5.38E-02
5.24E-04
3.79E-04
7.31E+00
1.92E+00
2.25E+00
5.92E-03
3.86E+00
3.13E+02
1.95E+02
1.39E+01
5.64E+00
5.74E+00
5.10E+00
2.62E+01
9.78E+00
1.35E+01
9.68E+01
1.30E+00
0.00E+00
1.34E+00
0.00E+00
4.86E-01
4.00E-01
1.16E+00
3.82E-01
1.81E-01
2.02E-02
1.15E-03
8.82E+01
6.82E-03
5.88E+00
1.23E-02
3.14E+01
0.00E+00
1.55E+03
2.24E+02
6.90E+01
2.87E+02
2.13E+01
8.64E+01
6.40E+01
5.26E+01
5.02E+01
2.64E+00
0.00E+00
1.28E+00
0.00E+00
5.00E-01
1.20E+00
4.19E+00
7.55E-01
6.21E-01
2.30E-02
4.64E-03
4.08E+01
4.13E-01
1.82E+00
2.33E-01
4.87E+01
0.00E+00
1.31E+02
1.61E+02
3.37E+01
2.29E+01
4.02E+01
7.33E+02
4.57E+01
1.40E+02
3.71E+00
2.44E+00
0.00E+00
1.43E+01
0.00E+00
9.38E-02
1.21E+00
1.39E-01
8.05E-01
1.99E-01
2.10E-03
1.76E-03
9.82E-01
1.20E-01
2.32E-01
7.25E-03
5.09E-01
0.00E+00
4.69E+00
9.97E-01
8.25E-02
8.93E-02
3.05E-01
3.54E+02
1.26E+00
1.60E-01
3.35E+00
7.90E-03
0.00E+00
0.00E+00
9.30E-04
0.00E+00
0.00E+00
8.08E-03
0.00E+00
3.70E-04
0.00E+00
0.00E+00
3.32E+00
0.00E+00
1.74E-02
0.00E+00
0.00E+00
3.28E+02
3.49E+01
2.69E-01
0.00E+00
0.00E+00
0.00E+00
0.00E+00
0.00E+00
0.00E+00
1.19E+01
1.00E+00
0.00E+00
1.27E-01
0.00E+00
4.73E-01
8.10E-02
3.08E-01
1.88E-02
7.60E-02
8.30E-04
3.50E-04
1.05E+01
6.17E-01
2.92E-01
9.95E-03
6.27E+00
1.96E+01
4.71E+01
7.74E+00
1.79E-01
6.74E-01
1.51E+00
5.44E+01
7.11E-01
4.28E+00
1.18E+01
1.02E+00
0.00E+00
1.27E-01
0.00E+00
3.68E-01
3.24E-02
3.00E-01
7.50E-03
7.42E-02
8.10E-04
3.36E-04
1.06E+01
4.31E-01
2.89E-01
9.71E-03
6.32E+00
1.37E+01
3.12E+01
7.62E+00
1.73E-01
6.36E-01
1.50E+00
5.11E+01
6.93E-01
4.22E+00
1.16E+01
1.02E+00
0.00E+00
1.27E-01
0.00E+00
2.73E-01
1.21E-02
2.97E-01
2.81E-03
7.35E-02
8.03E-04
3.28E-04
1.06E+01
2.59E-01
2.89E-01
9.62E-03
6.32E+00
8.23E+00
2.66E+01
7.31E+00
1.66E-01
6.27E-01
1.43E+00
4.98E+01
6.87E-01
4.02E+00
Table S2: Emission changes associated with AB 32 measures (tonnes/day). Please refer to the References section of the main article for full
reference information.
Simulated
AB 32 Scoping Plan Measure
Level
1
2
Sources
Energy Efficiency and Co- Benefits Audits for Large Industrial Sources
Industrial Electricity Generation
Oil and Gas Extraction GHG Emission Reduction
Oil and Gas Extraction Equipment
Natural Gas Transmission and Distribution GHG Emission Reduction
Natural Gas Transmission
Refinery Flare Recovery System Improvement
Petroleum Refining Flares
Removal of Methane Exemption from Existing Refinery Regulations
Petroleum Fugitive HC Pipeline Valves
Landfill Methane Control Measure
Commercial and Governmental Waste Disposal
Green Buildings
Electricity Generation from Coal
Increasing Combined Heat and Power Use by 30,000
GWh
Million Solar Roofs: 3,000MW by 2017
Electricity Generation from Distillate Oil
Water Use Efficiency
Electricity Generation from LPG
Water Recycling
Electricity Generation from Jet Fuel
Water System Energy Efficiency
Electricity Generation from Diesel
Reuse Urban Runoff
Electricity Generation from Natural Gas
Electricity Generation from Coke
Electricity Generation from Geothermal
Renewable Electricity Standard
Electricity Generation from Landfill Gas
Electricity Generation from Other
3
4
5
6
Energy Efficiency (Natural Gas)
Residential and Commercial Natural Gas
Water Use Efficiency
Residential and Commercial Natural Gas
Green Buildings
Residential and Commercial Natural Gas
Solar Water Heating: AB1470
Residential Natural Gas
Methane Capture at Large Dairies
Dairy Manure Waste
Dairy Biomethane Digester Combustion
Pavley (AB 1493)
On-Road Gasoline Vehicles
Pavley II
On-Road Gasoline Vehicles
Low Carbon Fuel Standard
On-Road Gasoline Vehicles
Regional Transportation- Related Greenhouse Gas Targets
On-Road Gasoline Vehicles
Tire Tread Program, Tire Pressure Program
On-Road Gasoline Vehicles
High Speed Rail
On-Road Gasoline Vehicles
Medium- and Heavy-Duty Vehicle Hybridization
On-Road Gasoline Vehicles
Port Drayage Trucks
On-Road Diesel Vehicles
Heavy-Duty Vehicle GHG Emission Reduction (Aerodynamic Efficiency)
On-Road Diesel Vehicles
Medium- and Heavy-Duty Vehicle Hybridization
On-Road Diesel Vehicles
Goods Movement System- Wide Efficiency Improvements
On-Road Diesel Vehicles
Low Carbon Fuel Standard
On-Road Diesel Vehicles
Transport Refrigeration Units Cold Storage Prohibition and Energy Efficiency
Transportation Refrigeration Units
Cargo Handling Equipment- Anti-Idling, Hybrid, Electrification
Industrial Off-road Equipment
Commercial Harbor Craft- Maintenance and Design Efficiency
Commercial Harbor Craft
Clean Ships
All Ocean Going Vessels
Clean Ships
Commercial Vessels
Vessel Speed Reduction
In-Transit Ocean Going Vessels
Ship Electrification at Ports
Berthing Ocean Going Vessels
High Speed Rail
Commercial Aircraft
Low Carbon Fuel Standard
Freight Trains
TOG
NMOG
CO
NOx
SOx
NH3
TSP
PM10
PM2.5
-5.28E+00
-4.47E-01
-2.00E+00
-4.64E+00
-1.44E-01
-2.63E+01
-2.43E-02
-3.70E-01
-4.04E-01
-5.77E-02
-5.80E-04
-4.10E-04
-1.94E+01
0.00E+00
5.69E+00
4.86E-02
-5.55E-01
-4.71E-01
-1.27E+00
-1.85E-02
-1.00E+01
2.29E+01
-3.41E+00
-4.90E+00
-4.38E+00
-5.97E+00
-8.53E-01
-3.04E+00
-6.34E+00
0.00E+00
-1.34E-01
-4.13E-01
-1.43E+00
2.27E-01
-3.42E+00
-4.20E-01
-1.93E+00
-1.62E+00
-2.73E-03
-7.49E-01
-1.42E+00
-8.67E-01
2.11E-01
-1.24E+00
-1.55E-01
-1.00E-01
-3.54E+00
-1.01E-01
-3.68E-01
-3.93E-03
-3.42E-01
-6.80E-02
-5.34E-02
-5.24E-04
-3.79E-04
-5.25E+00
0.00E+00
1.31E+00
3.76E-02
-4.19E-01
-1.50E-01
-4.06E-01
-1.40E-02
-1.00E+00
1.72E-04
-3.27E+00
-4.70E+00
-4.20E+00
-5.72E+00
-8.17E-01
-2.75E+00
-5.74E+00
0.00E+00
-1.26E-01
-3.88E-01
-1.34E+00
2.29E-01
-3.16E+00
-2.81E-01
-1.78E+00
-1.30E+00
-2.42E-03
-5.92E-01
-1.21E+00
-7.82E-01
3.09E-01
-3.18E+00
0.00E+00
0.00E+00
-6.68E-01
0.00E+00
0.00E+00
-4.00E-01
-1.16E+00
-3.82E-01
-1.77E-01
-2.02E-02
-1.15E-03
-5.72E+01
2.52E-03
5.52E+00
1.60E-03
-4.56E+00
-1.67E+00
-4.28E+00
-1.86E-01
0.00E+00
8.70E+01
-2.59E+01
-3.62E+01
-2.33E+01
-3.63E+01
-2.37E+01
-2.25E+01
-4.94E+01
0.00E+00
-2.13E+00
-6.57E+00
-2.27E+01
3.99E-01
-3.86E+01
-1.66E+01
-1.02E+01
-4.18E+00
-1.02E-02
-1.80E+00
-4.03E+00
-1.73E+01
0.00E+00
-5.09E+00
-1.16E+00
0.00E+00
-6.38E-01
0.00E+00
0.00E+00
-1.20E+00
-4.19E+00
-7.55E-01
-6.18E-01
-2.30E-02
-4.64E-03
-2.87E+01
2.40E-02
1.14E+00
9.00E-03
-9.47E+00
-2.67E+00
-6.11E+00
-2.73E-01
0.00E+00
2.29E+01
-1.94E-01
-1.36E+00
-7.44E+00
-3.39E+00
-1.94E-01
-4.54E+00
-3.68E+00
-3.46E+01
-1.57E+00
-4.30E+00
-1.74E+01
1.32E+00
-1.89E+01
-2.54E+00
-1.93E+01
-7.49E+01
-5.63E-02
-1.88E+01
-5.10E+01
-5.95E+00
2.07E+00
-3.53E-01
-2.33E-02
0.00E+00
-7.15E+00
0.00E+00
0.00E+00
-1.21E+00
-1.39E-01
-8.05E-01
-1.93E-01
-2.10E-03
-1.76E-03
-6.68E-01
0.00E+00
1.12E-01
2.90E-04
-9.37E-02
-2.60E-02
-7.35E-02
0.00E+00
0.00E+00
8.35E-02
-7.71E-02
-1.08E-01
-1.34E+00
-1.07E-01
-7.05E-02
-1.15E-01
-1.46E-01
-8.33E-02
-2.96E-03
-9.12E-03
-3.16E-02
7.57E-03
-4.62E-02
-5.32E-03
-1.46E-01
-2.32E+01
-2.70E-03
-1.10E+01
-2.60E+01
-1.64E-01
8.84E-03
6.66E-03
0.00E+00
0.00E+00
0.00E+00
0.00E+00
0.00E+00
0.00E+00
-8.08E-03
0.00E+00
0.00E+00
0.00E+00
0.00E+00
-2.26E+00
0.00E+00
9.07E-03
0.00E+00
0.00E+00
0.00E+00
0.00E+00
0.00E+00
-1.52E+02
0.00E+00
-5.62E-01
-7.86E-01
0.00E+00
-7.84E-01
-5.14E-01
-8.38E-01
-1.07E+00
0.00E+00
-2.00E-03
-6.18E-03
-2.14E-02
0.00E+00
0.00E+00
0.00E+00
0.00E+00
0.00E+00
0.00E+00
0.00E+00
0.00E+00
0.00E+00
0.00E+00
-2.52E-01
-7.06E-02
0.00E+00
-6.38E-02
0.00E+00
-1.81E-01
-8.10E-02
-3.08E-01
-1.88E-02
-7.56E-02
-8.30E-04
-3.50E-04
-7.06E+00
1.60E-01
1.74E-01
3.15E-03
-7.53E-01
-3.33E-01
-8.76E-01
-2.82E-02
0.00E+00
2.75E+00
-6.90E-01
-7.67E-01
-1.51E+00
-6.58E-01
-8.77E-01
-5.37E-01
-7.71E-01
-2.41E+00
-7.01E-02
-2.41E-01
-7.23E-01
-8.15E-01
-1.00E-01
-1.90E-02
-9.08E-01
-7.99E-01
-7.06E-04
-1.55E+00
-3.64E+00
-3.56E-02
4.21E-02
-2.50E-01
-7.26E-02
0.00E+00
-6.38E-02
0.00E+00
-1.27E-01
-3.24E-02
-3.00E-01
-7.50E-03
-7.38E-02
-8.10E-04
-3.36E-04
-7.15E+00
1.12E-01
1.74E-01
3.09E-03
-7.55E-01
-3.36E-01
-8.82E-01
-2.83E-02
0.00E+00
2.73E+00
-6.24E-01
-6.93E-01
-1.37E+00
-5.94E-01
-7.92E-01
-4.85E-01
-6.28E-01
-2.37E+00
-6.81E-02
-2.37E-01
-7.12E-01
-8.03E-01
-9.69E-02
-1.90E-02
-9.02E-01
-7.63E-01
-7.06E-04
-1.47E+00
-3.50E+00
-3.45E-02
4.11E-02
-2.46E-01
-7.26E-02
0.00E+00
-6.38E-02
0.00E+00
-7.61E-02
-1.21E-02
-2.97E-01
-2.81E-03
-7.31E-02
-8.03E-04
-3.28E-04
-7.15E+00
6.71E-02
1.73E-01
3.08E-03
-7.55E-01
-3.36E-01
-8.82E-01
-2.83E-02
0.00E+00
2.73E+00
-6.64E-01
-7.37E-01
-1.10E+00
-6.32E-01
-8.43E-01
-5.16E-01
-6.94E-01
-2.30E+00
-6.35E-02
-2.30E-01
-6.90E-01
-7.40E-01
-9.32E-02
-1.90E-02
-8.60E-01
-7.57E-01
-7.05E-04
-1.46E+00
-3.41E+00
-3.43E-02
4.12E-02
References
CARB Dec 2009, Worrel et al. 2008, Worrel et al. 2005,
Coito 2005, XENERGY Inc. 2001
CARB Sep 2008
CARB Sep 2008
CARB Dec 2008
CARB Sep 2008
R.W. Beck Inc. and Group Jun 2006, EPA 2011a, EPA 2011b
CEC Dec 2009b, CEC Dec 2005
CARB Dec 2008
CARB Dec 2008
CEC Nov 2005, CEC 2009a, Pacific Institute Sep 2005
CEC Nov 2005, CEC 2009a, CDWR Jun 2003
CEC Nov 2005, CEC 2009a, SWRCB Mar 2008
CEC Nov 2005, CEC 2009a, NRDC Aug 2009
CARB Apr 2010
CARB Apr 2010
CARB Apr 2010
CARB Sep 2008
CEC Nov 2005, CEC 2009a, Pacific Institute Sep 2005
Flex Your Power 2007
CARB Sep 2008
Shaw et al. 2007
See S.I. and text.
CARB Apr 2007
CARB Sep 2008
CARB Mar 2009
CARB Sep 2008
CARB Sep 2008
FRA Aug 2005
CARB Mar 2009
CARB Sep 2008
CARB Sep 2008
CARB Sep 2008
CARB Sep 2008
CARB Mar 2009
CARB Sep 2008
CARB Sep 2008
CARB Sep 2008
CARB Sep 2008
CARB Sep 2008
CARB Sep 2008
CARB Sep 2008
FRA Aug 2005
CARB Mar 2009
a) PM2.5 Mass Change
b) PM2.5 EC Change
c) PM2.5 OC Change
d) PM2.5 Sulfate Change
e) PM2.5 Nitrate Change
f) PM2.5 Ammonium Change
a) Cumulative PM2.5 OC Change
b) Level 1 Industry PM2.5 OC Change
c) Level 2 Elec. & NG PM2.5 OC Change
d) Level 3 Agriculture PM2.5 OC Change
e) Level 4 On-road Mobile PM2.5 OC Change
f) Level 5 Other Mobile PM2.5 OC Change
Fig. S1. January 2050 episode average PM2.5 Organic Carbon (OC) concentration changes (µg m-3) for all
defined AB 32 Implementation Levels. Panel (a) illustrates cumulative effects of all Levels while (panels
b-f) illustrate individual changes associated with each Level relative to the previous level. Red indicates
increased concentrations while blue indicates decreased concentrations.
a) Cumulative PM2.5 EC Change
b) Level 1 Industry PM2.5 EC Change
c) Level 2 Elec. & NG PM2.5 EC Change
d) Level 3 Agriculture PM2.5 EC Change
e) Level 4 On-road Mobile PM2.5 EC Change
f) Level 5 Other Mobile PM2.5 EC Change
Fig. S2. January 2050 episode average PM2.5 Elemental Carbon (EC) concentration changes (µg
m-3) for all defined AB 32 Implementation Levels. Panel (a) illustrates cumulative effects of all
Levels while Panels (b-f) illustrate individual changes associated with each Level relative to the
previous level. Red indicates increased concentrations while blue indicates decreased
concentrations.
a) Cumulative PM2.5 S(VI) Change
b) Level 1 Industry PM2.5 S(VI) Change
c) Level 2 Elec. & NG PM2.5 S(VI) Change
d) Level 3 Agriculture PM2.5 S(VI) Change
e) Level 4 On-road Mobile PM2.5 S(VI) Change
f) Level 5 Other Mobile PM2.5 S(VI) Change
Fig. S3. January 2050 episode average PM2.5 Sulfate (S(VI)) concentration changes (µg m-3) for
all defined AB 32 Implementation Levels. Panel (a) illustrates cumulative effects of all Levels
while (panels b-f) illustrate individual changes associated with each Level relative to the
previous level. Red indicates increased concentrations while blue indicates decreased
concentrations.
a) Cumulative PM2.5 N(V) Change
b) Level 1 Industry PM2.5 N(V) Change
c) Level 2 Elec. & NG PM2.5 N(V) Change
d) Level 3 Agriculture PM2.5 N(V) Change
e) Level 4 On-road Mobile PM2.5 N(V) Change
f) Level 5 Other Mobile PM2.5 N(V) Change
Fig. S4. January 2050 episode average PM2.5 Nitrate (N(V)) concentration changes (µg m-3) for
all defined AB 32 Implementation Levels. Panel (a) illustrates cumulative effects of all Levels
while (panels b-f) illustrate individual changes associated with each Level relative to the
previous level. Red indicates increased concentrations while blue indicates decreased
concentrations.