[PULL REQUEST] Revise N2O5 gamma calculation #913
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This commit addresses the issue in geoschem/geos-chem #907. In the computation of the gamma (rxn probability) for N2O5, the alpha factor (here called A) in routine N2O5_Inorg_Org can get too large. Viral Shah writes: The issue is that A scales as Volume/Surface area and becomes large for coarse-mode sea salt aerosols. The parameterization is based on the assumption that the N2O5 reaction is volume-limited, but Gaston & Thornton (2016) show that the reaction is largely diffusion-limited for particles larger than ~100 nm radius. I discussed this with Chris Holmes @cdholmes, and we propose to fix this by capping A to 3.2e-8, which is the value reported in Bertram & Thornton (2009). This sets the maximum gamma value to ~0.036, and would be consistent with the lab results. Signed-off-by: Bob Yantosca <yantosca@seas.harvard.edu>
yantosca
added
category: Feature Request
yantosca
changed the title
msulprizio
approved these changes
Sep 27, 2021
|
Now merged and tagged with 13.3.0-alpha.5 |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
This is the corresponding PR for Feature Request #907.
While this is a "one-liner" fix, we will run "alpha" benchmarks on this update, as it has the potential to significantly change the model results.