InMAP evaluation - Bay Area on-road mobile emission scenario

[bkoo-git]

This page discusses an InMAP test run for the impacts of the Bay Area on-road mobile emissions.

This test is similar to the Bay Area NGC emission scenario (#11), but the on-road mobile is a much larger source sector than the NGC in the Bay Area. CMAQ-estimated impacts of the Bay Area on-road mobile emissions were calculated using the brute-force method, similarly to the NGC test scenario. The InMAP meteorology/chemistry input data is the same as in the previous test case (#11 (comment)).

Comparison of the CMAQ and InMAP results is summarized here: InMAP_evaluation_BA_MB_2018_22May23.pptx

Tagging: @pmartien @dholstius @stephenreid65 @bujinb @marshalljulian @ctessum

[marshalljulian]

Thanks Bonyoung for this comparison. In the powerpoint file, slide #5 is helpful for seeing the magnitude of the similarities/differences. On that slide, it looks like many locations agree to within 30%-50% or better. All stations except Concord look to be within a factor of 2. (The difference at Concord looks like a factor of ~ 2.5.) Is that correct?

Ammonia seems to be an important contributor to the differences. Would it be possible to generate a version of slide #5 that is subdivided by chemical species (stacked bar chart, adding to the total concentration [ug/m3]), and also is grouped geographically (could be similar to the groupings in slide 6)?

[bkoo-git]

@marshalljulian Thanks for your comments. 10 out of 18 Bay Area sites show greater than 50% differences. I have prepared stacked bar charts as you requested (along with percent difference in total PM2.5 at each site):
InMAP_evaluation_BA_MB_2018_19Jun23.pptx

[marshalljulian]

Thanks, that's helpful. Based on those values, for the 'on-road mobile' comparison, InMAP results are ~50% larger than CMAQ, on average (conversely, CMAQ results are 30% less than InMAP). Ammonium seems to be the largest species contributing to that difference; if we estimated non-ammonium PM2.5 (removed ammonia from concentration estimates), the level of model-model agreement would likely improve noticeably. This result (i.e., InMAP overpredicts CMAQ for ammonia) likely holds for other sectors too, though another sector (having a substantially different spatial pattern in emissions) might yield different results for the CMAQ-InMAP model-model comparison.

…

On Mon, Jun 19, 2023 at 4:04 PM bkoo-git ***@***.***> wrote: @marshalljulian <https://github.com/marshalljulian> Thanks for your comments. 10 out of 18 Bay Area sites show greater than 50% differences. I have prepared stacked bar charts as you requested (along with percent difference in total PM2.5 at each site): InMAP_evaluation_BA_MB_2018_19Jun23.pptx <https://github.com/BAAQMD/InMAP-SFAB/files/11793839/InMAP_evaluation_BA_MB_2018_19Jun23.pptx> — Reply to this email directly, view it on GitHub <#14 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AEOOV3IY34E6M2KVJPTV7OTXMDLGTANCNFSM6AAAAAAYLBKGNU> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[bkoo-git]

@marshalljulian Actually, the largest contributor to the difference is nitrate: The stacked bars show sulfate, nitrate, ammonium, SOA, and primary PM2.5 from the bottom.
I think disagreement in spatial pattern is also a concern. InMAP predicts high contributions in some areas (e.g., Henry Coe State Park) where CMAQ shows only minor contributions (see slide 3 in the first PPT). Even with ammonium nitrate excluded (see below), the spatial discrepancies are still noticeable:

[marshalljulian]

you're right, it's nitrates -- I mis-read the colors. thanks.

…

On Wed, Jun 21, 2023 at 2:57 PM bkoo-git ***@***.***> wrote: @marshalljulian <https://github.com/marshalljulian> Actually, the largest contributor to the difference is nitrate: The stacked bars show sulfate, nitrate, ammonium, SOA, and primary PM2.5 from the bottom. I think disagreement in spatial pattern is also a concern. InMAP predicts high contributions in some areas (e.g., Henry Coe State Park) where CMAQ shows only minor contributions (see slide 3 in the first PPT). Even with ammonium nitrate excluded (see below), the spatial discrepancies are still noticeable: [image: cmaq_vs_inmap_wo_nh4no3] <https://user-images.githubusercontent.com/55764831/247771982-3114b533-88c8-4b89-b00a-0d28ef8d51dd.png> — Reply to this email directly, view it on GitHub <#14 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AEOOV3O352MRMB2ICBUP4FLXMNU53ANCNFSM6AAAAAAYLBKGNU> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[bkoo-git]

The InMAP input/output files for the Bay Area MB emission scenario are archived here.

InMAP emission input files: inmap_emiss_baaqmd_mb_2018.zip

InMAP output files: inmap_output_baaqmd_mb_2018.zip