Phone: 951 781-5797
Mail: CE-CERT, University of California; Riverside, CA
92521, USA
Email: carter@cert.ucr.edu
URL: http://www.cert.ucr.edu/~carter
| Date last updated |
|
| November 17, 2009 | This page |
| June 22, 2009 | Mechanism Documentation |
| March 16, 2009 | SAPRC-07 mechanism |
| July 13, 2009 | Condensed versions of SAPRC-07 |
| April 8, 2009 | "Toxics" versions of SAPRC-07 |
| September 10, 2009 | VOC reactivity scales |
| November 13, 2009 |
Mechanism implementation files for CMAQ |
| November 13, 2009 | Mechanism implementation files for SAPRC software |
Please note: An error was found in the SAPRC-07 mechanisms concerning peroxy + acyl peroxy radical reactions that affect predictions under low NOx conditions. Predictions of ozone, and MIR reactivity scales, should not be affected (though this will be checked), but correcting the error has non-negligible effects on predictions of low NOx species such as H2O2 and has large effects on predictions of organic acids under low NOx conditions. I am in the process of correcting the mechanism and will make corrected documentation and files available as soon as possible. Plese email me if you are using the SAPRC-07 mechanism and want additional information and notification when corrected files are available. (Files dated before November 17, 2009 will not have been corrected.)
Click here for the files implementing this mechanism for CMAQ., and click here for files implementing the mechanism in SAPRC software
The updated version of the SAPRC-99 mechanism, designated SAPRC-07, was completed in August and made available on this site at that time. Since then the mechanism and documentation have been updated several times. Given below is available documentation of this mechanism and and its associated reactivity scales.
Final report documenting the mechanism, its evaluation, and the updated reactivity scales. Available in Microsoft Word (saprc07.doc) and PDF (saprc07.pdf) formats. The current version is dated June 22, 2009.(Note: if these files open in your browser, use "save as" to save them as regular .DOC or .XLS files.)Tables in the Appendices to the report Excel format (saprc07.xls). This includes the large tables not in the main body of the report, the VOC reactivity tabulation (MIR and other scales) and uncertainty classifications in Table B-1 of the report, and other tables. The current version is dated June 22, 2009. Note that the reactivity tabulation in scales07.xls, dated September 10, 2009, has several new types of VOCs and corrections that are not incorported in thecurrent version of saprc07.xls, so it should be used for reactivity tabulations.
The table with the MIR and other reactivity data is also available in a separate Excel file (scales07.xls) that contains only this table and the associated footnotes. This includes the data in (saprc07.xls) that may be more useful for those only interested in the reactivity data. It also contains reactivity values for individual city-specific MIR, MOIR, and EBIR scenarios that are not in saprc07.xls. Note: The reactivities have been recalculated and the current listing supersedes versions dated July 7, 2008 and earlier. The current version is dated August 26, 2009. It also includes new VOCs added for the August, 2009 MIR update discussed in the MIR09 report discussed below. These VOCs are not yet included in saprc07.xls or the SAPRC-07 mechanism documentation report cited above.
A report discussing the update to the MIR values resulting from the use of the SAPRC-07 mechanism and describing the revised method used to calculate MIR values for the 24 hydrocarbon "bins" used in some CARB reactivity-based regulations is available in Microsoft Word (MIR09.doc) and PDF (MIR09.pdf) formats. The spreadsheet (HCcalc.xls) used to derive the compositions used to calculate the reactivities of the 24 hydrocarbon bins, which is referenced in the report, is also available. This can also be used to estimate compositions and reactivities of other hydrocarbon mixtures given type distributions and boiling point ranges. The current versions of the spreadsheet is dated June 22, 2009 and the report is dated September 10, 2009. The report includes several VOCs or mixtures added at the request of the CARB that are not in the June 22 version of the SAPRC-07 mechanism documentation report. However, these VOCs are in scales07.xls, which is also dated September 10, 2009.
The CARB contracted Merched Azzi, Richard Derwent, Robert Harley, and William Stockwell to conduct peer reviews of the SAPRC-07 mechanism. These reviews are available at the CARB RSAC website. My response to these reviews is available in Microsoft word (RespRev.doc) and PDF (RespRev.pdf) formats. This document is dated March 20, 2009.
The final report documenting the condensed versions of the SAPRC-07 mechanism is available. Available in Microsoft Word (csaprc07.doc) and PDF (csaprc07.pdf) formats. The report, which was revised to incorporate recent updates to the base mechanism, is dated July 13, 2009 and supersedes the July, 2008 version. The SAPRC-07 condensed mechanisms have been updated to be consistent with the current (3/30/09) version of SAPRC-07 and the files implementing these updated mechanisms are available on the "SAPRC-07 Chemical Mechanism and Emissions Speciation Files for CMAQ" page. The revised version dated July 13 was modified to retain methane, so it can be used for cleaner air simulations.The maximum ozone impacts of NO, NO2, and HONO, which have their highest positive impacts on ozone under very low NOx conditions, have been added to the reactivity tabulation in scales07.xls. These are more appropriate to use than MIR values for these NOx species for applications, such as life cycle analyses, where maximum ground-level ozone impacts of NOx are compared to those for VOCs. A report documenting the derivation of these NOx Maximum Incremental Reactivity (NMIR) values is available in Microsoft Word (NOxMIR.doc) and PDF (NOxMIR.pdf) formats. This report has not been updated to the current version of the mechanism, but NMIR the values tabulated in scales07.xls has.
A version of the distributed files and programs have been prepared, including files for the various versions of the SAPRC-07 mechanism (including condensed versions) and files to conduct chamber simulations and test calculations. This contains the corrected version of the mechanism and should replace any versions of the mechanism downloaded prior to April 9, 2009. Some of the programs have been updated as well. See the SAPRC mechanism files distribution page to download the files and for more information.
Changes and additions:
11/13/09: Minor corrections made to "C" versions of SAPRC07 and SAPRC07T. (This is the version that uses explicit reactions for peroxy radical operators to be consistent with most airshed model software. The correction involved adding 0.5 PROD to reactions of the xPROD operator with MEO2, RO2C, and RO2XC, for consistency with the treatment of these reactions in the "B" version. The effect on most model simulations should be negligible.) See distributions of mechanism files for CMAQ and the SAPRC software.A preliminary distribution of the files and programs used in the evaluation against the chamber data and other test calculations is now available. Go to files.htm for additional information and to download the files. Note that the documentation is only very preliminary and incomplete, and this has not been fully tested. The mechanism and programs are current as of April 9, 2009. If you need updated or additional files and information, please contact me.
11/12/09: Input and data files for simulations of chamber experiments for modeling using SAPRC software have been corrected and updated. A few experiments had errors in model simulation input files that were updated, and some experimental data files are missing. Input files and chamber data files should be current and complete for all experiments listed in Table C-1 in saprc07.xls.
9/9/09 and 8/26/09: The report documenting the MIR update (MIR09.pdf) has been updated and several VOCs and mixtures have been added. These new VOCs have also been added to scales07.xls. The mechanism documentation report (saprc07.pdf) and tabulations (saprc07.xls) have not yet been updated, so do not have all the reactivity values that are contained in MIR09.pdf and scales07.xls.
7/28/09: Files implementing SAPRC-07A, the otherwise uncondensed version of the mechanism using the SAPRC-99 peroxy radical operators, have been added to the files implementing the mechanism in CMAQ and the SAPRC software.
7/13/09: The condensed mechanism was revised to retain methane so it can be used in cleaner air simulations. The condensed mechanism documentation report (csaprc07.doc and csaprc07.pdf) was revised accordingly, and several corrections were made to the report. In addition, several corrections and updates were made to the files implementing the mechanism for SAPRC software.
6/22/09: The report to the CARB describing the update to the MIR scale and bin calculation method for their regulatory purposes (MIR09.pdf or MIR09.doc) was revised. This included revisions to the methods used to calculate the hydrocarbon Bin MIR's, so the reactivity and composition tabulations in the SAPRC-07 documentation report (saprc07.pdf or saprc07.doc and saprc07.xls) were revised accordingly.
6/8/09: The report and reactivity tabulations have been updated to include several new compounds and minor additions have been made to the mechanism documentation tabulations for a few other compounds.
4/9/09: The files implementing the SAPRC-07 mechanisms on SAPRC software, available on the SAPRC mechanism files page, have and the condensed SAPRC-07 mechanism report, been updated to be consistent with the current mechanisms as of this date.
4/8/09: The condensed and "toxics" versions of SAPRC-07 have been revised to be consistent with the 3/19/09 version of SAPRC-07, and the files implementing the various versions of SAPRC-07 have been prepared and are available on the "SAPRC-07 Chemical Mechanism and Emissions Speciation Files for CMAQ" page. The report documenting condensed SAPRC-07 still and the files implementing the mechanism in the SAPRC modeling software still need to be updated. Please contact me if you need the updated versions sooner.3/19/09: Changes have been made to the base SAPRC-07 mechanism to correct some errors found in the previous versions. The documentation report (saprc07.doc and saprc07.pdf) and the reactivity scales tabulations (saprc07.xls and scales07.xls) have been updated accordingly. The changes are summarized in Appendix E of the documentation report. (The condensed and "toxics" versions of SAPRC-07 and the available files not implementing the mechanisms were not updated until 4/8/09 -- see above.) These changes do not affect the emissions speciation assignments.
12/17/08: The final report for the condensed version of SAPRC-07 has been finalized and made available. Available in Microsoft Word (csaprc07.doc) and PDF (csaprc07.pdf) formats. Other than being finalized, the version is dated July 4, 2008 was unchanged.
7/7/08: Several corrections have been made to the mechanism and the documentation, reactivity scales, and mechanism files have been updated accordingly.
7/7/08: Files for the preliminary "toxics" version of of SAPRC-07, designated SAPRC07T have been added. This is being developed for the EPA for implementation in CMAQ. See the readme file for the current SAPRC-07T distribution.
6/3/08: The CARB hydrocarbon bins have been added to the reactivity tabulation in Table B-2 (scales07.xls). The compositions used to derive the reactivities of the bins have been added to Table B-10, which is included in saprc07.xls. Footnotes to Table B-2 references how these bin compositions were derived.
5/28/08: A number of corrections were made to the mechanism, the documentation report was updated, and the reactivity scales were recalculated. Any versions of the documentation, mechanism files, or reactivity tabulations uploaded prior to this date need to be replaced by the current versions. See Appendix E in the documentation report (e.g., saprc07.pdf). The changes in reactivity values compared to the 12/31/07 version were small except for 1,1-dichloroethene, where there was an error in the rate constant that was corrected.
1/22/08: The maximum ozone impacts of NO, NO2, and HONO, which have their highest positive impacts on ozone under very low NOx conditions, have been added to the reactivity tabulation in scales07.xls. A report documenting the derivation of these values is available in Microsoft Word (NOxMIR.doc) and PDF (NOxMIR.pdf) formats. Also, the tabulations in scales07.xls also give the reactivities in the individual MIR, MOIR and EBIR as well as base case scenarios.
12/31/07. Documentation report and mechanism and reactivity tabulations updated to incorporate results of recent studies of the mechanism of methyl iodide (Carter, 2007) and of amines and several other consumer product VOCs (Carter, report on CARB Contract 06-408, in preparation). The mechanism and reactivity values for methyl iodide have been added, the mechanisms and reactivity values have changed for all amines, and several consumer product VOC have been added. The amine reactivities in previous tabulations should not be used. Reactivities have not changed for any other previously tabulated compounds.
6/28/07. Error in Table B-1 in saprc07.xls and scales07.xls corrected. The previous version had incorrect standard deviations for the "Base" reactivities.
8/31/07. A number of errors in the report have been corrected when preparing the final (8/31/07) version. See the summary of revisions.
8/31/07. The mechanism as listed in the June 15 version of the report had two errors. Reaction BR08 should be changed from "RO2C + HO2 = HO2" "RO2C + HO2 =" and reaction BR13 should be changed from "RO2XC + HO2 = HO2" to "RO2XC + HO2 =". This has been corrected in the current (8/31) version of the report and reactivity scales. The change has only small effects on O3 and reactivity scales, but a non-negligible effect on calculations of HO2 in low NOx scenarios.
Carter main web page Current version of distributed files for SAPRC-07, with test and chamber simulations using SAPRC software Current version of the files implementing this mechanism for CMAQ Files specifically for the EPA SAPRC07T Project (subset of those above). Emissions speciation project containing assignments of emissions categories to model species in SAPRC and other mechanisms The following links give information about SAPRC-99:
SAPRC-99 mechanism documentation report Latest VOC Reactivity tabulations for SAPRC-99 Mechanism Files implementing SAPRC-99 Chemical Mechanism and Associated Software Current Information on Emissions Speciation Database Work