NOAA CSL is collaborating with the U.S. Environmental Protection Agency (EPA) and university partners to create and maintain a community chemical mechanism – Community Regional Atmospheric Chemistry Multiphase Mechanism (CRACMM) – in order to improve prediction and forecasting of air quality.
CRACMM aims to:
Improve the representation of emissions and their chemistry
Accurately represent air toxics, aerosols, and ozone together in one common mechanism
Remain computationally feasible for current operations
Leverage community knowledge
NOAA CSL's contribution to the CRACMM effort will include:
Advance the chemistry of anthropogenic, biogenic, and wildfire emissions
Capture future atmospheric chemistry changes due to changes in NOx levels
Evaluate and advance CRACMM using NOAA field campaigns including those that have focused on the urban environment in the recent past:
2021 Southwest Urban NOx and VOC EXperiment (SUNVEx) campaign
2023 Atmospheric Emissions and Reactions Observed from Megacities to Marine Areas (AEROMMA) campaign
2024 Utah Summer Ozone Study (USOS) campaign
Implement CRACMM into NOAA modeling infrastructure including the Unified Forecasting System with chemistry (UFS-Chem)
Use CRACMM to better understand which emission sources contribute most to formation of common air pollutants such as ozone and secondary organic aerosol (SOA) and to evaluate and inform the design of reduced complexity mechanisms for use in computing-intensive experiments