https://doi.org/10.5061/dryad.f7m0cfz3w

Description of the data and file structure

Source: Assembled and calculated by authors

This dataset comprises a series of CSV files generated from WRF-CMAQ simulations for June to August 2018 (JJA2018). The data capture variables across seven different sites, including planetary boundary layer heights, biogenic emissions, and both surface and column concentrations.

File Naming Convention

Files are named following the pattern: Sitei_Hourly_data source_varname_JJA2018.csv

- Sitei represents the site name associated with the data.

- Hourly indicates that the data was collected on an hourly basis.

- data source and varname refer to the specific data source and variable names as described above.

Data Sources and Variables

All data files include the following common columns:

• site: site name.
• datetime, Date Local, Time Local: Columns representing the local date and time for each row of data. Timestamps follow a 24-hour clock format (from 00:00 to 23:00), for example: 6/1/18 4:00, 6/1/18, 4:00.

Below is a breakdown of each data source_varname file type and the variables they contain:

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WRF_PBL

• Description: Planetary Boundary Layer height from the Weather Research and Forecasting (WRF) model.
• Units: Meters (m)
• Variable(s):
  • PBL_m: Planetary boundary layer height in meters.

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B3GTS_S

• Description: Biogenic emissions derived from the Biogenic Emission Inventory System (BEIS).
• Units: Kilograms per hour (kg/hr)
• Variable(s):
  • Variables are formatted as:\
    B3GTS_S_{species name}_kgPhr\
    Example: B3GTS_S_FORM_kgPhr (for formaldehyde)
  • Includes biogenic emissions for 22 species.

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CMAQSurfACONC

• Description: Hourly averaged surface-level concentrations from WRF-CMAQ simulations.
• Units: Parts per million by volume (ppmv)
• Variable(s):
  • Variables are formatted as:\
    CMAQSurfACONC_{species name}_ppmV\
    Example: CMAQSurfACONC_NO_ppmV (for nitric oxide)
  • Includes data for 7 chemical species.

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CMAQVCDTrop

• Description: Approximated tropospheric vertical column densities from WRF-CMAQ simulations.
• Units: Molecules per square centimeter (molec/cm²)
• Variable(s):
  • Two separate files:
    • CMAQVCDTrop_HCHO_molecPcm2: Tropospheric column density of formaldehyde (HCHO).
    • CMAQVCDTrop_NO2_molecPcm2: Tropospheric column density of nitrogen dioxide (NO₂).

Data Approximation Methodology

The geographic coordinates for each site are detailed in Supplement Table S1. The values in the CSV files represent the nearest land-based pixel to these coordinates selected from the original model simulations, which have a horizontal resolution of 1.33 km x 1.33 km. To approximate surface concentrations, we utilize data from the near-surface layer. For calculating the tropospheric vertical column densities (VCDTrop), we aggregate number densities up to the tropopause, which we define consistently across the dataset as a pressure of 200 hPa—corresponding to an altitude of roughly 13 km at a latitude near 40° N. We advise users to incorporate the nuances of our approximation methods and the specificity of the data’s geographic sourcing in any subsequent analyses to maintain the integrity of their research findings.