Title: Incremental Testing of the Community Multiscale Air Quality (CMAQ) Modeling System Version 4.7
1Incremental Testing of the Community Multiscale
Air Quality (CMAQ) Modeling System Version 4.7
- Shawn J. Roselle, K. Wyat Appel, Kristen M.
Foley, Prakash V. Bhave, - Jonathan E. Pleim, Rohit Mathur, Tanya L. Otte,
Robert C. Gilliam, - Golam Sarwar, Christopher G. Nolte, Alice B.
Gilliland, - Robert W. Pinder, and Jenise L. Swall
2Acknowledgements
- Model Developers contributing to CMAQv4.7
- Jesse Bash
- Prakash Bhave
- Arastoo Pour Biazar (UAH)
- Frank Binkowski (UNC)
- Russ Bullock
- Ann Marie Carlton
- Ellen Cooter
- Bill Hutzell
- Jim Kelly (now with CARB)
- Rohit Mathur
- Sergey Napelenok
- Chris Nolte
- Tanya Otte
- Jon Pleim
- George Pouliot
- Shawn Roselle
- Golam Sarwar
- Donna Schwede
- WRF simulations
- Rob Gilliam
- Tanya Otte
- Jon Pleim
- Support model simulations, emissions
processing, data extractions, IC/BCs - Lucille Bender (CSC)
- Charles Chang (CSC)
- Ryan Cleary (CSC)
- Steve Howard
- Allan Huffman (CSC)
- Nancy Hwang (CSC)
- Lara Reynolds (CSC)
-
3Science Improvements for CMAQv4.7
- Aerosols
- Heterogeneous reaction probability (?N2O5)
- Re-derived parameterization based on Davis et al.
(2008) - SOA Model Enhancements (presentation by S.
Napelenok) - Updates isoprene SOA, sesquiterpene SOA,
polymerization, acid-catalyzed SOA, NOx-dependent
SOA yields, and enthalpy of vaporization (Edney
et al., 2007) - In-cloud SOA formation pathways (glyoxal,
methylglyoxal) (Carlton et al., 2008) - Changes in gas-phase chemistry mechanism,
emissions speciation, and biogenic emissions
model, to represent SOA precursors - Coarse PM (poster by J. Kelly and P. Bhave)
- Semi-volatile inorganic components (NO3-, Cl-,
and NH4) can condense and evaporate from the
coarse mode, via dynamic mass transfer - Nonvolatile sulfate can condense on the coarse
mode - Variable standard deviation of coarse mode size
distribution - Emissions of sea salt from the surf zone
4Science Improvements for CMAQv4.7 (cont.)
- Chemistry
- HONO enhancements (Sarwar et al., 2008)
- Heterogeneous reaction on aerosol and ground
surfaces - Emissions from mobile sources
- Photolysis Options (beta versions)
- In-line photolysis rate module, with aerosol
feedback (Binkowski et al., 2008) (poster by C.
Nolte) - Photolysis rates adjusted using satellite-derived
cloud information (currently table-approach only)
(Pour Biazar et al., 2008) - Aqueous Chemistry
- Added two organic oxidation reactions (glyoxal,
methylglyoxal) (Carlton et al., 2008) - Updates to Henry's Law constants based on
literature review - Base CB05 mechanism with Cl2 chemistry (Yarwood
et al., 2005) - Multi-pollutant Capability
- Include HAPs and Hg in single modeling platform
(presentation by W. Hutzell)
5Science Improvements for CMAQv4.7 (cont.)
- In-line options
- Dry Deposition
- Moved calculation into CCTM
- Emissions (poster by J. Young)
- Integrated BEIS into CCTM
- Incorporated Plume-rise into CCTM
- Bi-directional NH3 and Hg surface flux (optional)
- For NH3, fertilizer emissions will be applied
through the flux model (under development) - Emissions
- Biogenic emissions added sesquiterpene
emissions - Speciation changes for HONO and benzene
- Sea-salt emissions
- Updated flux parameterizations surf zone
emissions - Used Spatial Allocator to produce ocean file
6Science Improvements for CMAQv4.7 (cont.)
- Clouds
- Convective cloud model
- Revised to reduce layer configuration differences
- Changed the integration timestep
- Resolved cloud model
- Correction in precipitation flux calculation
7Incremental Testing
- This release was incrementally tested for
extended time periods - January August 2006
- 12 km eastern U.S. domain (nested from 36 km
continental U.S. domain) - 34 vertical layers (no layer collapsing)
- Operational evaluation performed for each major
science increment - Transition from MM5 to WRF (poster by W. Appel)
- All simulations presented here used WRF2.2
- Benefits
- Diagnostic evaluation
- Documents the impact of each model change on
performance - Provides more detailed information regarding
differences in results between model release
versions - Provided QA/QC for model simulations, input data,
and implementation
8Incremental Simulations
- BASE Modified version of CMAQv4.6 that included
chlorine chemistry - GAMMA N2O5 New parameterization for ?N2O5
- SOA New SOA module
- HONO Surface HONO reactions and HONO emissions
- COARSE MODE Addition of Dynamic coarse mode
- CLOUDS Revised convective and resolved cloud
models - CMAQv4.7 Final release version
9Model Bias in SO4 --- CASTNET Weekly Observations
August 2006
January 2006
Sulfate model performance improved with cloud
model revisions
10Model Bias in NO3 --- CASTNET Weekly Observations
August 2006
January 2006
Base model used Evans and Jacob (2005)
parameterization, that included a sign error
11Model Bias in TNO3 --- CASTNET Weekly Observations
August 2006
January 2006
Again, base model used Evans and Jacob (2005)
parameterization, that included a sign error
12Model Bias in NH4 --- CASTNET Weekly Observations
August 2006
January 2006
13Model Bias in OC --- IMPROVE Daily Observations
August 2006
January 2006
Model value Observed value (µg/m3)
Model value Observed value (µg/m3)
Note primary reason for decrease in OC is change
in enthalpy of vaporization
14Model Bias in TC --- STN Daily Observations
August 2006
January 2006
15Model Bias in SO4 Wet Deposition --- NADP Weekly
Observations
August 2006
January 2006
Model value Observed value (kg/ha)
Model value Observed value (kg/ha)
16Model Bias in NO3 Wet Deposition --- NADP Weekly
Observations
August 2006
January 2006
17Model Bias in Cl Wet Deposition --- NADP Weekly
Observations
August 2006
January 2006
Model Bias improved with the addition of dynamic
coarse mode
18Model Bias in 8-hr. Max. O3 --- AQS Daily
Observations
Model value Observed value (ppb)
19Other Changes for CMAQv4.7
- MCIPv3.4 required (soon to be released)
- Diagnostic Tools (will be released later this
year) - Direct Decoupled Method (DDM)
- Primary carbon source apportionment model
- Sulfate tracking model
- Model options removed
- Plume-in-grid
- CB4 mechanisms
- Aero3 module and AE3 mechanisms
- RADM cloud module
- Stand-alone mercury version of CMAQ (capability
is included in the multipollutant version)
20Model Development for Future CMAQ Releases
- Two-way Coupled WRF/CMAQ (presentations by J.
Pleim and D. Wong) - Chemistry
- Alternative gas-phase chemical mechanisms
(SAPRC-2007, RACM2) - Continued development of the inline photolysis
module - Aerosols
- Speciation of fine soil, non-carbon organic
matter - Source Apportionment of PMother
- Influence of organics on ?N2O5
- Thermodynamics of crustal/soil species
- Clouds
- Rosenbrock solver for aqueous chemistry
- Grell convective cloud module
- Dry Deposition
- Mosaic land-use approach
- National Land Cover Data (NLCD)