Hello, everyone,
The attached figure is the spatial distribution of sea spray concentration from the CMAQ simulation ran by myself. I feel strange that the sea spray concentration is not zero (0.1-0.3 ug/m3) inland so far from the ocean. Is my modeling result incorrect or is the non-zero continental sea spray concentration due to dynamical processes? Thank you very much for your reply!
Best wishes,
Lingyun
The pink values and especially the sharp gradients between pink and green values over land suggest that the OPEN and SURF fields in your OCEAN file are spatially misaligned with your modeling domain. When you plot OPEN and SURF with the same method you use to plot the sea salt concentrations above, what do you see?
Hi @hogrefe.christian,
Thank you very much for your help!
The spatial distributions of OPEN and SURF are as followed:
The non-zero values of OPEN along the states’ boundary are very small (~10^-15).
The white color indicates zero or NaN value.
Best wishes,
Lingyun
Thanks for posting these. As another check, could you please also share a plot of the LWMASK and PBL fields from your MCIP files?
Thank you very much for your advice.
Here are the figures for LWMASK and PBL at 8am, 2pm, and 6pm
Thank you again!
All the best,
Lingyun
By the way. The simulation date is 2021/06/25.
Thank you. The gradients in the PBL pattern at 12UTC seem to line up pretty well with the gradients in the ASEACAT patterns at 14UTC in your initial plot, with areas of very low PBL corresponding to areas of ASEACAT > 0.9 and vice versa (just to confirm, what you label SEAS_COARSE in your plot is the CCTM output species ASEACAT, correct?).
How far into the simulation is the ASEACAT plot you showed? Do initial conditions still play a role, and if yes, what was the initial condition field for ASEACAT? If it’s further into the simulation, have you looked at animations of ASEACAT to see if there is a circulation pattern that advects sea salt inland and to which extent the higher ASEACAT concentrations over land vary diurnally? What boundary conditions are you using in your simulation, and what are the sea salt concentrations in those boundary conditions? Advection of coarse mode sea salt over land in conjunction with shallow mixing layers certainly can cause areas and time periods with concentrations > 1 ug/m3. That said, using a coarser color scale that goes to 20 or 40 ug/m3, you should still see the expected ocean/land gradients.
If you would like to dig deeper into the evaluation of CMAQ sea salt aerosol, these publications are good starting points:
Kelly et al., 2010
Gantt et al., 2015
Thank you very much for such detailed suggestions! Yes, the label SEAS_COARSE is the CCTM output species ASEACAT. I ran the simulation since 2021/06/18, regarding the first week (06/18-06/24) as the spin-up period. I will check the evolution of ASEACAT and wind field hour by hour and the spatial distribution of ASEACAT in the initial and boundary conditions according to your suggestions.
Thank you again!
Have a good weekend,
Lingyun
