Current Project Information Page
Development of an Improved Chemical Speciation Database
for Processing Emissions of Volatile Organic Compounds for Air Quality
William P. L. Carter
College of Engineering, Center for Environmental Research and Technology
University of California, Riverside, CA 92521
Database last updated Dedember 30, 2022
Programs or input files last updated November 20, 2014
Page last updated December 30, 2022
This database gives
model species assignments for various chemical mechanisms for for use
with various emissions profile database for organic compounds emitted
into the atmosphere. This database can be used to assign model species in (currently) 15 different
chemical mechanisms to total organic gas (TOG) speciation profiles in 5
different profile databases. A manuscript describing the database
and its assignments for various emissions and profile databases has been published in the Journal of the Air & Waste Management Association
(W. P. L. Carter, "Development of a database for chemical mechanism
assignments for volatile organic emissions," J. Air & Waste
Management Association, Volume 65, Issue 10, pages 1171-1184, 2015, DOI: 10.1080/10962247.2015.1013646) and is also available upon request. A
users manual also describing this database and associated programs and
files and discussing how to install and use them is available here. The assignments are incorporated in two Excel
spreadsheets, one of which has macros to output the assignments in files for use with
existing speciation processing systems. Fortran programs were developed to use the
assignments to make GSPRO files for SMOKE, and files output by the system can
be imported directly into the Speciation Tool.
Developing these assignments
required creating a unified organic compound and mixture classification
assigning compounds to mixtures, assigning model species to compounds
various mechanisms, and developing procedures for processing these
and also making assignments for unknown, unassigned, or nonvolatile
mass. The database files and associated programs and documentation can
be downloaded from this location.
In addition, ozone reactivity values in the MIR, MOIR, and EBIR scales have been
estimated for all the gas-phase organic speciation profiles in the Speciate 4.3
database. These include upper, lower, and best-estimate reactivity
estimates in each scale. The report consists of a document (Speciate-Reactivity.pdf) describing the objectives and methodology employed and a spreadsheet (Speciate-Reactivity-Appendix.xls) containing the tables with the results. The report is dated November 21, 2013.
Note that the database structure and associated programs and documentation were revised and made available on 2/10/14. See the web page for the previous version for a discussion of the previous version of the database and the programs and a list of updates prior to that date.
What's New (updates after 2015)
- Assignments have been updated for a preliminary version of
SAPRC-22, which will supercede SAPRC-18 once it is finalized. More
information about SAPRC-22 will be made available soon.
- Assignments have been added for SAPRC-18, which supercedes SAPRC-16. Information about SAPRC-18 is available at the SAPRC-18 web site.
Documentation and Database files
SpecDB.pdf (Dated January 21, 2015): Documentation and users manual for the current database and files
SpecDB.zip (December 30, 2022): All files and programs discussed in SpecDB.pdf. (Note that these do not contain the SAPRC-16 and MOZART assignments)
- SpecDB.xls (December 30, 2022): Spreadsheet with speciation assignments and macros to output
files for speciation processing by SMOKE and the Speciation Tool
- MechDB.xls (December 30, 2022): Spreadsheet listing model species and related information for
the supported mechanisms. Needed by the macros in SpecDB.xls.
- Added assignments for a preliminary version of SAPRC-18, an update to SAPRC-18. This is still for initial testing and review only. Please contact me if you want to work with this mechanism.
assignments for a preliminary version of SAPRC-18, an update to
SAPRC-16. This will be superceded by SAPRC-22.
assignments assignments for the SAPRC-16 mechanims, a major update to
the SAPRC mechanisms. This will be superceded by SAPRC-22.
- Assignments have been added by the MOZART-T1 mechanism. These were
made by Geoff Tyndall, John Orlando and Christoph Knote and provided by Christoph
Knote on 8/17/15.
- A few assignments to NROG or NVOL were made for compounds
assigned for MOZART that weren't previously assigned for other
- Updated the users manual document to include an improved discussion of
how to install the files and test the installation and how to add new
mechanisms or support for additional profile databases.
- Updated the documentation sheet to be more constent with the currrent database.
- Deleted mechanisms that are still under development or whose assignmets are incomplete.
- Made various corrections to assignments and categories
- Added new categories and compounds found in Speciate 4.4.
- Added Smiles strings for many compounds and a few new CAS numbers using the SmileCas database.
- Added CO as an explicit species for all mechanisms. Was previously assigned as unreactive.
- Renamed some SAPRC07 model species to be consistent with emissions surrogate names currently used in CMAQ.
- Added BENZENE and SESQ to CB05, since these are used for SOA modeling for CB05 in CMAQ.
category numbers for uncertain mixture categories and changed
assignments categories refering to salts, elements, and PM to
- Model species for SAPRC-99 and SAPRC-07T changed to be consistent with
implementation of these mechanisms in CMAQ. Note that this means that
SAPRC-99 now has separate model species for benzene and sesquiterpenes.
- Programs and macros changed to allow for more than 8-character model species names (except for Carbon Bond-type mechanisms).
- Format of GSPRO files output by SpecDB.xls and ProfAsn.exe changed from fixed width to CSV.
to output BEIS 3 emissions replaced by a general GSPRO output macro.
(The previous macro did not output NROG in mass units.)
- Assignments for BEIS 3 biogenic emissions categories updated and macros to output GSPRO for BEIS3 has been added.
- MEGAN 2.1 biogenic emissions assignmnets for the 18 biogenic VOC categories
- A number of biogenic VOCs have been added to the list of compounds
- Preliminary model species assignments have been made for BEIS 3 biogenic organic emissions categories. These are subject to change.
- SAPRC-11D model species added for cis-3-hexen-1-ol and cis-3-hexenyl acetate.
[top of page]