This page last reviewed August 10, 2009

Control Strategy Modeling Section
Research Program


Internal Research

Modification of the UAM-FCM Code to Process SAPRC99

The Urban Airshed Model with the Flexible Mechanism (UAM-FCM) is an adaptation of the Urban Airshed Model (UAM) to provide flexibility in incorporating different photochemical mechanisms. The original UAM-FCM software had the capability to process the SAPRC mechanism through the 1997 version update (see contract below). However, the most recent version of the SAPRC chemical mechanism (SAPRC99) includes new features that are not addressed by the UAM-FCM software.

To maintain CARB's capability to test and implement state-of-the-art photochemical mechanisms, including SAPRC99, Control Strategy Modeling Section (CSMS) staff modified the UAM-FCM program code. Dr. William Carter generously prepared the necessary input files that are read by the UAM-FCM for processing SAPRC99. The revised UAM-FCM, dated 122601, (which includes input files to process CB-IV, SAPRC90, SAPRC93, SAPRC97, SAPRC99f, and SAPRC99P) and User's Guided are available for download. A hard copy of the User Guide (which includes some figures and Appendix 3 not available in the electronic format) can be obtained via U.S. mail for a fee of $10.00 to cover copying costs and postage.

Download Modified UAM-FCM code in a gzip'ed tar file (2,378,061 bytes)

Download FCM User Guide, in WordPerfect 5.1 format (254,547 bytes)


Photochemical Grid Modeling


Mesoscale Meteorological Modeling


Simulation Evaluation



Extramural Research


Assessment of Effects of Chemical Mechanism Uncertainty on Airshed Model Results

Contract Manager: Dr. Luis Woodhouse

Investigators: Dr. William Carter (SAPRC); Mr. Frederick Lurmann (STI) and Dr. Naresh Kumar (STI)

Objectives: Provide the tools and information necessary to understand the effects of chemical mechanisms uncertainties on regulatory model predictions of effects of changes in ROG and NOx emissions on ozone formation.

Findings: This project ended on May 30, 1996. The objectives of this project were not fully achieved and a new contract was put in place (see contract below) to complete the goals. The main product of this contract was the development of the Flexible Mechanism Software (FCM) which is a generalized procedure for implementing both lumped molecule mechanisms, like the SAPRC mechanism, and lumped structure mechanisms, like CB-IV, into the Urban Airshed Model (UAM). The software generates mechanism-specific chemical kinetic data files and FORTRAN subroutines for use in the UAM. The FCM code and User Guide is available for download.

Download FCM code in a zip file (546,518 bytes)

Download FCM User Guide, in WordPerfect 5.1 format (254,547 bytes)


Effects of Chemical Mechanism Uncertainty on Airshed Model Results

Contract Manager: Dr. Luis Woodhouse

 Investigators: Dr. Gery Whitten (SAI), Dr. Dongfen Gao (SAI), Mr. Thomas Myers (SAI), and
Mr. James P. Killus.

 Objectives: Provide the information necessary to understand the effects of chemical mechanisms uncertainties on regulatory model predictions of effects of changes in ROG and NOx emissions on ozone formation.

 Findings: Contract ended June 30, 1998.  This contract was conducted in two phases.  Phase I included a review of sources of uncertainties in the Carbon Bond IV (CBIV) atmospheric reaction mechanism, development of the high and low radical flux versions of CBIV, and performance evaluation of these two CBIV versions against selected smog chamber experiments.  Phase II included results of implementing the high and low radical flux versions of CBIV in a box-model and in the airshed model.  Reports are available for each phase of the contract.

Download Phase I Report (1.25MB)

Download Phase II Report (1.9MB)



Critical Evaluation of a Biogenics Emission System for Photochemical Grid Modeling in California

Contract Manager: Mr. Bruce Jackson

 Investigator: Dr. Arthur Winer, UCLA

Objectives: Critically review and update biomass and emission factor databases. Assess utility of aerial imagery. Critique current vegetation emission inventory models. Identify gaps in databases and needed research. Develop verification procedures for biogenic emissions estimates used in photochemical models.

 Findings: (No reportable results available at this time.)
 


Horizontal Advection Solver Uncertainty

Contract Manager: Mr. Donald Johnson

 Investigator: Dr. M. Talat Odman, MCNC

 Objectives: Investigate errors introduced in photochemical grid models by the horizontal advection solvers used and to assess the sensitivity of model predictions to these errors by testing and evaluating alternative advection schemes.

 Findings: This project ended on 30 June, 1996.

Download Final_Report.tar.gz (7,574,136 bytes)

The advection solver routines used in the project is available for download.

Download carb.tar.gz (51,766 bytes)




Tracking the Sacramento Ozone Plume Over the Western Sierra Nevada

Contract Manager: Mr. Leon Dolislager - Research Division

 CSMS Contact: Mr. Bruce Jackson

 Investigator: Dr. John Carroll, UC-Davis

 Objectives: Conduct mobile three dimensional sampling to define the temporal and spatial variation of the pollutant plumes over the western slopes of the Sierra east and north east of Sacramento. These data will be used to re-examine transport hypotheses and to identify areas where significant gradients or major flow transitions occur.

Findings: (No reportable results available at this time.)



Southern California Draft Gridded Emissions Inventory

Contract Manager: Mr. Bruce Jackson

 Investigator: Ms. Julie Fieber, PE, Systems Applications International

 Objectives: Prepare the basic components needed to construct a gridded emissions inventory for broader southern California as a foundation for development of future gridded inventories for regional ozone modeling.

 Findings: (No reportable results available at this time.)

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