Table 1.
Site information for the Los Angeles Megacity Carbon Project surface network. Continuous measurements from the CIT, CNP, MWO, SBC, and PVP sites are not included as part of this study.
| Code | Full site name | Inlet height (ma.g.l.) | Site elevation (ma.s.l.) | Lat (° N) | Long (° W) | Analyzer |
|---|---|---|---|---|---|---|
| VIC | Victorvillea | 100/100/50 | 1370 | 34.61 | 117.29 | Picarro G2301 |
| GRA | Granada Hillsa | 51/51/31 | 391 | 34.28 | 118.47 | Picarro G2401 |
| USC-1 | downtown LA (University of Southern California)b,c | 50 | 55 | 34.02 | 118.29 | Picarro G2301 |
| USC-2 | downtown LA (University of Southern California)b,c | 50 | 55 | 34.02 | 118.29 | Picarro G2401 |
| COM | Comptona | 45/45/25 | 9 | 33.87 | 118.28 | Picarro G2401 |
| FUL | Fullerton (CSU Fullerton)b | 50 | 75 | 33.88 | 117.88 | Picarro G2401 |
| IRV | Irvine (UC Irvine)b | 20 | 10 | 33.64 | 117.84 | Picarro G2301 |
| SCI | San Clemente Islanda | 27 | 489 | 32.92 | 118.49 | Picarro G2401 |
| ONT | Ontarioa | 41/41/25 | 260 | 34.06 | 117.58 | Picarro G2301 |
| CNP | Canoga Park* | 15 | 245 | 34.19 | 118.6 | Picarro G2301 |
| LJO | La Jolla (Scripps Pier)b | 13 | 0 | 32.87 | 117.25 | Picarro G2301 |
| CIT-1 | Pasadena (Caltech, Arms Laboratory)b,d,* | 10 | 230 | 34.14 | 118.13 | |
| CIT-2 | Pasadena (Caltech, Millikan Library)d,* | 48 | 230 | Picarro G2401 | ||
| MWO | Mt. Wilsonb,e,* | 3 | 1670 | 34.22 | 118.06 | |
| PVP | Palos Verdes Peninsulab,* | 3 | 320 | 33.74 | 118.35 | |
| SBC | San Bernardinoa,b,* | 27/58 | 300 | 34.09 | 117.31 | Picarro G2301 |
Tower sites include VIC, GRA, COM, SCI, ONT, and SBC. All other sites have rooftop configurations (USC, FUL, IRV, CIT, and CNP), with air inlets plumbed to the four corners of the building, sampling each corner every 15 min (similar to McKain et al., 2015). For rooftop configurations, “upwind” hourly averages are computed using data from the upwind corner of the building determined based on the corner with the highest wind speed measurement. Rooftop inlet height indicates the total height above the surface (building + mast).
indicates the flask collection site for 14C observations (during current or past studies). CO2 flask observations began near the LJO site in 1979 but are not included as part of this study. The Earth Networks configuration at LJO was implemented in January 2012 with an inlet that is located near Scripps Pier.
USC: at the time of this study, the USC site had two Picarro analyzers installed (model G2301 and G2401), referred to here as USC-1 and USC-2, respectively.
CIT: flask observations at the Caltech Arms Laboratory site (CIT-1) began in 1998. The CIT-1 site has a Picarro G1101-i (isotopic CO2 analyzer) with continuous measurements of 12CO2 and 13CO2 as described previously (Newman et al., 2008, 2013, 2016) and, since roughly 2001, has had an LGR (Los Gatos Research) N2O/CO EP analyzer installed. The Caltech Millikan Library site (CIT-2) was installed nearby in December 2015 and includes a Picarro G2401 analyzer. The Millikan site has a four-corner rooftop sampling strategy identical to other rooftop sites, while the Caltech Arms Laboratory site is a building site with a different configuration. Results are not included as part of this study.
MWO: flask data have been collected by NOAA/ESRL since 2010 and are included as part of the background analysis in this study. At the time of this study, there were three continuous analyzers installed at the California Laboratory for Atmospheric Remote Sensing (CLARS) facility near MWO, which are managed by the Air Resources Board: Picarro G2201-i analyzer measuring CH4/13CH4/CO2, Picarro G5310 measuring N2O/CO/CO2, and an LGR model 913–0015 measuring N2O/CO.
Continuous measurements from the CIT, CNP, MWO, SBC, and PVP sites are not included as part of this study. Some data from the CIT-1, PVP, MWO, and SBC sites have been described previously (e.g., Hsu et al., 2010; Jeong et al., 2013; Newman et al., 2013). At the time of this study, the PVP site also had a continuous CO2 analyzer installed (PP Systems CIRAS-SC) and the SBC site also had an LGR N2O/CO EP analyzer.