Slide1 :
Expanded Ozone Forecast Guidance
for the National Air Quality Forecast Capability
NWS/NCEP/EMC & NOAA/OAR/ARL - EPA
September 18, 2007
Acknowledgements : Acknowledgements NCEP/EMC
Pius Lee – System design and implementation
Marina Tsidulko – PBL & Chem Verification
Youhua Tang – Regional In-line testing (OAR/GSD)
Ho-Chun Huang – Global dust/smoke system DT&E (NASA, NESDIS)
Sarah Lu – Global data assimilation and feedback testing (NASA, NESDIS)
Brad Ferrier, Dan Johnson – WRF retrospective run
Eric Rogers, Hui-Ya Chuang – NAM products
Jeff McQueen – EMC AQ model team leader
EPA AQ Forecast team (Mathur, Kang, Lin, Yu…)
2007 Developments : 2007 Developments WRF upgrades
Land use/Roughness length corrections: reduce Pac. NW high moisture bias
Enhanced horizontal diffusion on sloping terrain
CMAQ Improvements
Common NMM vertical coordinate
Asymmetric Convective Model (ACM-2) PBL parameterizations
Area & Point emissions updated for 2007
California 2002 NEI emissions modified for biases
Corrections to deposition velocity & plume rise calculations
AQF system retrospective & Real-time testing
July 22- Aug 5 2006 with experimental CONUS configuration
Verification
Spatial map comparisons to observations (03 & PBL hgt)
Inclusion of NESDIS GASP AOD products
Focus group, TEXAQS06 & SHENAIR projects
Forecast Domains (2005-2007) : 268 grid cells 259
grid
cells East “3x” Domain Forecast Domains (2005-2007) CONUS “5x” Domain
WRF-CMAQ
WRF-CMAQ/PM
2006-2007 Systems NAM/WRF-CMAQ 48 h forecasts : 2006-2007 Systems NAM/WRF-CMAQ 48 h forecasts
NAM-CMAQ Coupling : NAM-CMAQ Coupling
Summer 2007 Evaluations (Errors not uncovered w/retro tests) : Summer 2007 Evaluations (Errors not uncovered w/retro tests) Experimental/Developmental Runs: Significant under-prediction in upper Mid-West
Deposition Velocity
Added Mesophyll component for O3, NO, NO2
STATUS: Implemented inexper/dev runs on July 22
Minor impact on forecast Increased photochemistry in Midwest
Plume Rise
STATUS: Corrected in exper/dev run on July 22
minor impact
EMC Products 1h, 8h avg O3 / Daily Max/ hourly biases : EMC Products 1h, 8h avg O3 / Daily Max/ hourly biases
EMC Web Products 1h, 24h avg hrly & Max PM & Profiles : EMC Web Products 1h, 24h avg hrly & Max PM & Profiles
EMC Web Products Near Real-time Verification : EMC Web Products Near Real-time Verification CMAQ 8 h Max Ozone CMAQ vs GASP AOD HYSPLIT vs NESDIS Smoke Conc
Slide11 : Daily 8hr max Ozone Biases Op vs Exp over Eastern U.S. Summer 2006
(after NAM upgrade) Summer 2007 Both Op and Experimental Runs improved in 2007
For Operational run, NAM improvements partially responsible
Slide12 : Daily 1 & 8h Max Ozone Skill Scores 2007 Operational (3X) vs Experimental (5X) Equitable Threat Score ~ H/(O+F-H) 1hr Avg Thresholds (ppb) 8 hr Avg Thresholds (ppb) Experimental:
- Better performance at low/moderate ranges & in East U.S.
- Comparable at high thresholds
Slide13 : SW Coast
includes both
LA, SD & SJV Verification Sub-domains
Regional Performance, 1-h O3 Experimental Run Bias Reduced in 2007 : Regional Performance, 1-h O3 Experimental Run Bias Reduced in 2007 2006 2007 2006
High bias, up to +25 ppb
Underprediction SW coast 2007
Bias reduced
Good forecast for NW coast
Underprediction SWC (LA basin)
Regional Performance, 1-h O3 Experimental Bias Improved Over Operational Run : Regional Performance, 1-h O3 Experimental Bias Improved Over Operational Run Operational Bias 2007 Experimental Bias Experimental Bias improved over operational system over all regions
California Air Districts : California Air Districts
California Performance : California Performance Good: SAC, SJV
Under: LA
Over: East of LA Good: SJV
Under: LA
Over: SAC, East of LA Good: SJV
Under: LA
Over: SAC, East of LA
NAM vs RTMA 10 m Winds July 3rd 5 PM, 36 hour Forecasts : NAM vs RTMA 10 m Winds July 3rd 5 PM, 36 hour Forecasts LA Basin: NAM Temps are warmer; winds are stronger & more westerly NAM RTMA
NAM 2m Dew point Errors SW Coast (green triangles) : NAM 2m Dew point Errors SW Coast (green triangles) BIAS by Forecast hour
BIAS for each day
Slide20 : W-E NOx cross-section thru LA Basin
36 hour forecast: July 3, 2007 5 PM July 5, 2007 5 PM Lofting of plume above boundary layer can allow further
transport of pollutants East of LA Land ocean
Mid-Atlantic 8h Max Performance July 9, 2007 : Mid-Atlantic 8h Max Performance July 9, 2007 NAM is slightly cooler than observed in PA and W. NJ
Continued overprediction along CT coastal regions NAM –RTMA: 2 m T
Mid-Atlantic 8 h Max Performance July 10, 2007 : Mid-Atlantic 8 h Max Performance July 10, 2007 Very Similar performance between operational and experimental
Mid-Atlantic 8 h Max Performance July 10, 2007 : Mid-Atlantic 8 h Max Performance July 10, 2007 Convective precip started earlier than predicted in Mid-Atlantic NAM 3h Precip Prediction Precip Analysis
8h Max Ozone Regional Performance August 7, 2007 : 8h Max Ozone Regional Performance August 7, 2007 Operational Experimental Over-prediction in both runs: cloud cover timing ?
Exp 8h Max Texas Performance August 11, 2007 : Exp 8h Max Texas Performance August 11, 2007 Ozone buildup over stable marine layer w/ 5X. This residual layer can recirculate onshore. Not as strong in 3X.
Inconsistent met & chemical boundary layers OPERATIONAL EXPERIMENTAL 12Z 8/10/07 NAM-CMAQ 36 h forecast
5x-3x NOx differences & H20v
Slide26 : Exp – Op Ozone Difference
12 Z August 10, 2007 Forecast ocean Land
Summary : Summary Overall results
Experimental biases are much improved
NAM changes from 2006 to 2007 also have a positive impact (as Operational run biases improved)
Skill scores are improved at lower levels and comparable at higher thresholds
Experimental run provides previously unavailable guidance to Western U.S.
California O3 forecasts improved
Better performance in San Joaquin Valley
Underprediction in LA urban area
Some Overprediction in Sacramento Valley & downwind of LA
NAM onshore winds near LA often too strong
Spurious upward lofting partially due to inconsistent NAM and CMAQ daytime unstable PBL physics (Vertical resolution may also have an impact)
5X overprediction along coastal urban areas
ACM-2 stable, marine PBL mixing may be too weak
Produces pollutant reservoir off-shore that can impact coastal urban areas (Houston, Long Island Sound, Lake Michigan…)
Recommendations : Recommendations Implement consistent boundary layer and cloud mixing schemes
Internal boundary layer processes near coastal regions
Increase focus on chemical data assimilation in Global GSI
Improve coordination with AQF ESRL/GSD data assimilation
LA Basin
NMM high resolution experiments in coordination with ESRL/ PSD NMM study
More complete chemistry
CB05 more heterogeneous chemistry with aerosols
Improved boundary conditions
GFS-GOCART, HYSPLIT
Spatially & Temporally varying Lateral Boundaries (currently static)
Reduced gas phase chemistry (eg: RAQMS, GOloff & Stockwell, 2002)
Slide29 : 2-D advection test with 15th layer wind Initial conditions formed with a cuboid between the 15th and 17th layers in the NMM domain center. Future Work:
Inline Chemistry (WRF-NMM-Chem)
Youhua Tang & Georg Grell Mass not conserved when only
2-d and 3-D advection used
Future Work: Global Aerosol Forecasting & Data Assimilation (Sarah Lu, H-C Huang, Mian Chin…) : Future Work: Global Aerosol Forecasting & Data Assimilation (Sarah Lu, H-C Huang, Mian Chin…) NCEP CFS – GOCART Interactive Chemistry
BACKUPS : BACKUPS
Exp 8h Max Regional Performance August 2, 2007 : Exp 8h Max Regional Performance August 2, 2007 CIN CHAR ATL LOU NASH PIT Good forecasts for moderate event
in PIT, DC, PHL, S. CT , Charlotte,
Louisville, Cincinnati (clear skies)
Regional Performance, Max 8-h O3 Bias Reduced in 2007 : Regional Performance, Max 8-h O3 Bias Reduced in 2007 Bias, 2006 Bias, 2007 2006
High bias, up to +25 ppb
Underprediction NW coast
Underprediction SW coast 2007
Bias reduced
Good forecast for NW coast
Underprediction SWC (LA basin)
Slide34 : Daily 8h Max Ozone Biases Experimental (5X) run: All Sub-region biases 5X :
Under-prediction in California
Over-prediction in NW coast (for mod O3)
SW coast biases similar for both Summers Summer 2007
Slide35 : Daily 8h Max Ozone Skill Scores 2007 Operational (3X) vs Experimental (5X) Operational: Better performance for high thresholds (8 hr standard >85 ppb)
Experimental: Better performance at low/moderate ranges, worse over West POD=H/F FAR=1-H/F
PBL Height Verification July 2007 (00Z, 5 PM PDT) : PBL Height Verification July 2007 (00Z, 5 PM PDT) Ri marine pbl estimates may be too low
Acknowledgements : Acknowledgements NOAA/OAR
Rohit Mathur – ASMD AQ team leader
Daiwen Kang – CMAQ verification, PM testing
Shaocai Yu – CMAQ diagnostic studies
Hsin-Mu Lin – PREMAQ development
Jon Pleim – CMAQ met processing development
J. Young, David Wong – Code optimization
George Pouliot, Daniel Tong – Emissions processing