CMAQ Bugfix Branch

CMAQ Version X+ Overview

New CMAQ versions are released on the 'main' branch. After a CMAQ release an additional bugfix or 'X+' branch is created. The X+ branch is a continually evolving branch and is intended for users who wish to adopt the most recent bugfixes or minor updates that improve model stability, efficiency, etc. The X+ code has not been thoroughly evaluated or characterized so users must assume the risk of any unforeseen and undocumented impacts of code changes that have been incorporated since the most recent documented public release. The thoroughly vetted version of these bugfixes and updates are then included in the next public release of CMAQ. For example, after CMAQv5.3.3 was released, a 5.3.3+ branch was added. All of the tagged updates in the 5.3.3+ branch were then released with CMAQv5.4.

Below is the record of tagged bugfix versions for each CMAQ release.

Record of changes to CMAQv5.4+

Tag	PR Number	PR Name	Merge Date	Brief Description
CMAQv5.4.0.1_7Dec2022
	#183	Enable DDM-3D and ISAM calculations and output for Potential Vorticity option	2022-12-07	Inadvertently, DDM-3D and ISAM code were not functioning with the CMAQ 5.4 release when the potential vorticity option was enabled during compilation. This pull request corrects both models.
	#182	Add precision to logfile process timing	2022-12-02	At high computational efficiency, the default precision provided for the timing metrics in the logfile was yielding 0.0. This PR adds 3 decimal places of precision to the timing output.
	#181	Resolve time-stepping issue in ELMO when used within WRF-CMAQ and MPAS-CMAQ	2022-12-02	ELMO gives erroneous results in WRF-CMAQ and when using met inputs not aligned with hour time steps. This PR resolves the problem by adjusting the algorithm for identifying when the initial time step is hit for the simulation and synchronization cycles.
	#180	BDSNP fix	2022-12-02	Online nitrogen deposition (NDEP) is erroneously enabled when using BDSNP in the released version of CMAQ 5.4. This PR corrects an IF statement that was meant to disable online nitrogen deposition.

Record of changes to CMAQv5.3.3+

Note, each tagged version of CMAQv5.3.3+ contains all updates from previous versions.

Tag	PR Number	PR Name	Merge Date	Brief Description
CMAQv5.3.3.3_10May2022	#168	WRF-CMAQv533+	2022-05-10	Script and documentation update to ensure streamlined building of the WRF-CMAQ model intended for users who would like to run CMAQv5.3.3+ with WRFv4.4+.
CMAQv5.3.3.2_7May2022	#171	Remove files from chemistry utilities causing problems on MAC and WINDOWS systems	2022-05-07	Both the create_ebi and inline_phot_prerproc utilities have files in their source code directories that only differ in letter case in filenames. The property does not cause problems on Linux systems but can cause problems on Window and Macintosh systems. The pull request removes the unneeded files causing the problems.
CMAQv5.3.3.1_11Feb2022
	#163	Resolve Bug for reading Emission Stream Families	2022-02-09	Bug fix to avoid errors when processing matches for emission stream families related to capitalization.
	#164	Resolve bug in Low-NOx formation of SOA	2022-02-09	A typo in the SOA_DEFN data table resulted in high NOx reactions contributing to low-NOx species, which are quite low in volatility. This bug fix has a considerable impact on SOA if using AE6. No impact for AE7.
	#165	Bugfix Speed up emissions processing in PTMET subroutine	2022-02-09	The PTMET subroutine is streamlined so that it is not run for every point source and every stream every time each stream is called. This update drastically reduces runtimes in areas where there happen to be lots of point sources on a particular processor. No impact on results.