Data contact: Havala Pye, ORCID: 0000-0002-2014-2140 2023 CMAQ Simulation output for select sites in the Northeast US - CMAQ simulations performed by Havala Pye ORD/CEMM/AESMD - simulation labels: cmaq55plus (base) and cmaq55plus_nofire (wildfire, agricultural fire, and prescribed fire emissions in US and outside US set to zero) - Description: CMAQv5.5+ public version downloaded 2/13/2025. (SHA: 783dc11668a83b9ec243c2cf7d20471ecd34dfae). Last Merge on 5.5 plus: Jan 31. Chemical mechanism: CRACMM2. Dry deposition: STAGE with Emerson et al. 2020 aerosol parameters. Vertical diffusion: acm. Windblown dust emissions: on. Sea spray emissions: on. Lightning NOx: on. Land surface model: PX. Bidirectional ammonia exchange: on. Fertilizer NH3 emissions: computed in-line. HONO production on ground surfaces: on. Gravitational settling of aerosols: on. Scale free trop O3 to potential vorticity: off. Biogenic emissions: BEIS in-line. Aerosol optics: approx of Mie Theory for internally homogeneous particle. WRF v4.6.0. BCON: GEOSCF mapped to cracmm2. Solver: EBI. Compiler: Intel 23.2. OMI file set to use 2019 data. Entire month of December 2022 (using representative days) discarded as spinup. HAP emissions are from explicit emission factors rather than VOC speciation. Species definitions file for post processing concentrations updated 2/27/2025. Simulations and post-processing performed by Havala Pye. - Original file locations: /work/MOD3DEV/has/2023cracmm_ages/runs/ Files were created by the write site program distributed with CMAQ (https://github.com/USEPA/CMAQ/blob/main/POST/writesite/README.md). Species included are defined in terms of raw models species in SpecDef_Conc_cracmm2_v2.txt. The description of raw model species is at https://github.com/USEPA/CRACMM/blob/main/metadata/cracmm2/cracmm2_metadata.csv. Log files for the write site program are included as writesite*.txt. A jupyter notebook in ipynb and html format shows some of the data. Please cite the following for CMAQ with CRACMM2: Skipper, T. N., D'Ambro, E. L., Wiser, F. C., McNeill, V. F., Schwantes, R. H., Henderson, B. H., Piletic, I. R., Baublitz, C. B., Bash, J. O., Whitehill, A. R., Valin, L. C., Mouat, A. P., Kaiser, J., Wolfe, G. M., St. Clair, J. M., Hanisco, T. F., Fried, A., Place, B. K., and Pye, H. O. T.: Role of chemical production and depositional losses on formaldehyde in the Community Regional Atmospheric Chemistry Multiphase Mechanism (CRACMM), Atmos. Chem. Phys., 24, 12903–12924, https://doi.org/10.5194/acp-24-12903-2024, 2024. DISCLAIMER: This data product has been reviewed in accordance with U.S. Environmental Protection Agency policy and approved for public release. At the time of release, the data had not yet been published in peer-reviewed literature. The data is provided for research and the user should verify the data is suitable for their intended use.