Hello!
I am running the two-way coupled WRF(v4.5.1)-CMAQ(v5.5) model over a Midwestern US domain (centered over Chicago IL at the base of Lake Michigan). I developed emission inputs using the 2022v1 emission modeling platform. For this setup, we are using the CB6rAE7 mechanism (B10C6AE7). ICON and BCON files are from different sources (GEOS-CHEM using Barron Henderson’s AQMBC code, EPA 12km CMAQ model output). This is a recent model build, and while CMAQ is able to run without crashing, the model output is questionable.
Specifically, the model output simulates very high concentrations of various species (e.g., NO, NO2, HONO) over rural regions of the domain and appears to be systematic as they persist across different model days and months, regardless of ICON/BCON files (NO_conc, NO2_conc image below). I do see evidence of 2D emissions being correctly imported into the model (e.g., on-road pollution peaks during rush hour within model output); however, I am unsure what is causing concentration to be larger within rural regions compared to urban areas.
Not all pollutants have erroneously high values, some look reasonable and align with output from the previous setup using older model versions (CO_conc image). 2D emissions also appear comparable to older model versions (not shown below).
Last thing of note, when visualizing pollutant species I often associate with biogenic sources, some time steps within the model do not always accurately reflect Lake Michigan’s shoreline, and other times seem to reflect coarse grid structure or possibly an issue with downscaling the biogenic inputs. I’ve attached an example of this as well.
I’ve attached the runscript for CMAQ and a few screen grabs of model output. I would appreciate any help in identifying what may be causing erroneously high values or recommended diagnostics to further isolate the issue. Thank you in advance for your help!
run_cctm_Bench_20230708_Chicago_LADCO.WRFCMAQ_d03_BASE_all_layers_part1.csh (54.1 KB)