S
1
Sup
porti
ng
information
f
or
:
Methane emissions from dairy operations in California’s San Joaquin Valley
evaluated using airborne flux measurements
Benjamin C. Schulze
1
,
Ryan X. Ward
1
, Eva Y. Pfannerstill
2
, Qindan Zhu
3*
, Caleb Arata
2,10
,
Bryan
Place
5**
, Clara Nussbaumer
3,6
, Paul Wooldridge
3,5
,
Roy Woods
7
,
Anthony Bucholz
7
, Ronald C. Cohen
3,5
,
Allen H. Goldstein
2,4
, Paul O. Wennberg
1,8
, John H. Seinfeld
8,9
1
Division of Geological and Planetary Sciences, California Institute of
Technology
, Pasadena, CA
2
Department of Environmental Science and Policy Management, University of California Berkeley, Berkeley, CA
3
Department of Earth and Planetary Sciences, University of California, Berkeley, Berkeley, CA
4
Department of Civil and Environmental Engineering, University of California, Berkeley, Berkeley, CA
5
Department of Chemistry, University of California, Berkeley, Berkeley, CA
6
Department of Atmospheric Chemistry, Max Planck Institute for Chemistry, Mainz, Germany
7
Department of Meteorology, Naval Postgraduate School, Monterey, CA
8
Division of Engineering and Applied Science, California Institute of Technology, Pasadena, CA
9
Division of Chemistry and Chemical Engineering, California Institute of Technology
10
Picarro Inc., Santa Clara, CA
*Now at Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology,
Cambridge, MA
**Now at Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park,
NC
S
2
T
able of c
ontents
1.
Calibration of the Picarro G2401
-
m
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......
3
2.
Description of the disjunct eddy covariance flux calculation using the continuous wavelet transform
(CWT)
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3
2.1
Uncertainties in calculated EC fluxes
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5
2.2
Systematic uncertainties
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5
2.3
Random errors
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6
2.4
Correction of EC fluxes for vertical flux divergence
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....
7
3.
Flux footprints
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.......
8
4.
Uncertainties in mass balance emission calculations
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8
5.
Estimation of point
-
source, natural gas, and cropland methane emissions within the mass balance
region
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10
6.
Description of positive matrix factorization (PMF) analysis
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12
6.1
Overview
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.....
12
6.2
Data preparation
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..........................
12
6.3
Selection of PMF solution
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13
6.4
Factor descriptions
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16
6.4.1
Non
-
dairy agriculture
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..........
16
6.4.2
Cold
-
start combustion
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.........
16
6.4.3
Power
-
generation/refineries
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17
6.5
Quantification of factor uncertainties
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.........................
17
6.6
Comparison of methane source distribution inferred from PMF with results of Guha et al.
(2015)
19
7.
Calculation of dairy methane emissions in the surveyed regions using CARB inventory emission
factors
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..........................
19
8.
Calculation of the temperature dependence of dairy methane emission factors
................................
.
21
9.
Figures S1
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S26
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24
10.
Tables S1
-
S6
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51
11.
References
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57