Mobile ground-based measurements of methane mixing ratios at New York state landfills
Abstract
Methane (CH4) concentrations were measured from ground-level mobile monitoring at New York State (NYS) landfills over three separate field campaigns in 2021 and 2022. The data files are broken up by year and site visited. Methane was measured by both an Aerodyne Dual Quantum-Cascade LAS (QCLS) and a Picarro G2204 cavity ring-down spectrometer.
Both the QCLS and Picarro spans were calibrated with a two-tank calibration pre- and post-deployment, and the zero-offset was measured throughout each field campaign. Calibration tanks are traceable to standards calibrated by the Central Calibration Laboratory (CCL) at the National Oceanographic and Atmospheric Administration (NOAA) Global Monitoring Laboratory in Boulder, CO, which maintains the World Meteorological Organization (WMO) CH4 scale (WMO X2004A). Both CH4 datasets were also corrected for drift in the analyzer clock and response time from inlet overflow checks. Since the QCLS measured a consistently higher baseline than the Picarro, the Picarro data was baseline-corrected to the QCLS. Missing QCLS data were supplemented with available Picarro data.
The datasets also include the measured latitude and longitude coordinates and meteorological parameters from the nearest NYS Mesonet station (Brotzge et al., 2020). These meteorological parameters were averaged between the stations and include temperature at 2 m (C), ambient station pressure (mb), average wind speed (m/s) and direction (degrees) at 10 m, and solar insolation (W/m^2).
Dataset DOI: 10.5061/dryad.g4f4qrg1x
Description of the data and file structure
Methane concentrations were measured using ground-level mobile monitoring. The dataset includes latitude, longitude, meteorological data, and two separate measurements of methane concentrations.
Files and variables
File: Data.zip
Description: The data files are broken up by each field campaign from June 2021, November 2021, and July 2022. The filename is the site visited, e.g. in the June 2021 folder the filename millseat_0614.csv is the data measured from Mill Seat Landfill on 06/14/2021.
Each dataset contains 1 second data of the time and GPS coordinates, surface temperature (C), station pressure (mb), wind speed (m/s) at 10 m, wind direction (degrees) at 10 m, solar insolation (W/m^2), and the methane variables. The meteorological variables were averages of the nearest NYS Mesonet stations to the landfill (Brotzge et al., 2020).
The methane variables were measured by an Aerodyne QCLS and a Picarro. The dataset provides both measurements in ppb and ppm. The calibrated and inlet overflow time-corrected data for both measurements are listed as: CH4_ppm_qcls, CH4_ppb_qcls, CH4_ppm_picarro, CH4_ppb_picarro. Since the Picarro baseline was consistently lower than the QCLS, the Picarro data was baseline- and peak-corrected to the QCLS. Any missing QCLS data was then supplemented by the Picarro data. These variables are: CH4_ppm_qcls_scaled, CH4_ppb_qcls_scaled, CH4_ppm_picarro_scaled, CH4_ppb_picarro_scaled.
Reference:
Brotzge, J. A.; Wang, J.; Thorncroft, C. D.; Joseph, E.; Bain, N.; Bassill, N.; Farruggio, N.; Freedman, J. M.; Hemker, K.; Johnston, D.; Kane, E.; McKim, S.; Miller, S. D.; Minder, J. R.; Naple, P.; Perez, S.; Schwab, J. J.; Schwab, M. J.; Sicker, J. A Technical Overview of the New York State Mesonet Standard Network. J Atmos Ocean Technol 2020, 37 (10), 1827–1845. https://doi.org/10.1175/JTECH-D-19-0220.1