ARL Weekly News – November 4, 2022

Recent Events

HYSPLIT V8.0 Upgrade Test Begun

NCEP Central Operations, or NCO, has begun the 30 day test of HYSPLIT  model version 8.0.5. Once  successfully completed, the National Weather Service will benefit from a number of new features will be with this upgrade:

Science updates:

  • Improved initialization of turbulent velocity – Set a minimum value for roughness length
  • New plume rise algorithm added
  • New options for computing Lagrangian time scale
  • New convective schemes
  • Minimum mixed layer depth changed from 0 to 25 m

Technical updates:

  • Added ability for circular emissions area
  • Plotting updates (gridplot, trajplot, concplot, volcplot) new algorithm for determining spatial extent
  • Cleaning of code including removing unused variables and fixing uninitialized variables
  • Inclusion of an ensemble dispersion capability to predict and quantify Volcanic Ash plume uncertainty using the 31 member NWS Global Ensemble Forecast Capability (GEFS) v12 to drive the dispersion.
  • Creation of ARL-Packed format High Resolution Ensemble Forecast (HREF) 10 member predictions input files to drive HYSPLIT hazardous release ensemble predictions. These input files for HYSPLIT will be available on the NWS Web Operation Center (WOC) server (password protected).
  • Creation of a Time of Arrival graphic for radiological plume prediction as requested by the World Meteorological Organization (WMO) Regional Specialized Meteorological Center (RSMC) Expert Team on Emergency Response Activities (ET-ERA).

More information on the service change is available from NWS

IMPROVE Network Steering Committee Meeting

Xinrong Ren attended the Interagency Monitoring of Protected Visual Environments (IMPROVE) network Steering Committee meeting (in-person) in Plymouth, NH on November 2-3 . Meeting attendees including representatives from federal and state agencies, academia, and nonprofit environmental organizations, who are involved activities in the operations, data analysis, and management of the IMPROVE monitoring network. As one of the IMPROVE Steering Committee members representing NOAA, Dr. Ren was involved in the discussion of the IMPROVE business, including the establishment of the IMPROVE charter and three subcommittees to contemplate the future structure and function of the Steering Committee and to enhance the awareness and usage of the data of the IMPROVE network in the science community.

Papers Published

Evaluation of the NAQFC driven by the NOAA Global Forecast System (version 16): comparison with the WRF-CMAQ during the summer 2019 FIREX-AQ campaign

Tang, Y., Campbell, P. C., Lee, P., Saylor, R., Yang, F., Baker, B., Tong, D., Stein, A., Huang, J., Huang, H.-C., Pan, L., McQueen, J., Stajner, I., Tirado-Delgado, J., Jung, Y., Yang, M., Bourgeois, I., Peischl, J., Ryerson, T., Blake, D., Schwarz, J., Jimenez, J.-L., Crawford, J., Diskin, G., Moore, R., Hair, J., Huey, G., Rollins, A., Dibb, J., and Zhang, X.: Evaluation of the NAQFC driven by the NOAA Global Forecast System (version 16): comparison with the WRF-CMAQ during the summer 2019 FIREX-AQ campaign, Geosci. Model Dev., 15, 7977–7999,, 2022.

Abstract: The latest operational National Air Quality Forecast Capability (NAQFC) has been advanced to use the Community Multiscale Air Quality (CMAQ) model (version 5.3.1) with the CB6r3 (Carbon Bond 6 revision 3) AERO7 (version 7 of the aerosol module) chemical mechanism and is driven by the Finite-Volume Cubed-Sphere (FV3) Global Forecast System, version 16 (GFSv16). This update has been accomplished via the development of the meteorological preprocessor, NOAA-EPA Atmosphere–Chemistry Coupler (NACC), adapted from the existing Meteorology–Chemistry Interface Processor (MCIP). Differing from the typically used Weather Research and Forecasting (WRF) CMAQ system in the air quality research community, the interpolation-based NACC can use various meteorological outputs to drive the CMAQ model (e.g., FV3-GFSv16), even though they are on different grids. In this study, we compare and evaluate GFSv16-CMAQ and WRFv4.0.3-CMAQ using observations over the contiguous United States (CONUS) in summer 2019 that have been verified with surface meteorological and AIRNow observations. During this period, the Fire Influence on Regional to Global Environments and Air Quality (FIREX-AQ) field campaign was performed, and we compare the two models with airborne measurements from the NASA DC-8 aircraft. The GFS-CMAQ and WRF-CMAQ systems show similar performance overall with some differences for certain events, species and regions. The GFSv16 meteorology tends to have a stronger diurnal variability in the planetary boundary layer height (higher during daytime and lower at night) than WRF over the US Pacific coast, and it also predicted lower nighttime 10 m winds. In summer 2019, the GFS-CMAQ system showed better surface ozone (O3) than WRF-CMAQ at night over the CONUS domain; however, the models’ fine particulate matter (PM2.5) predictions showed mixed verification results: GFS-CMAQ yielded better mean biases but poorer correlations over the Pacific coast. These results indicate that using global GFSv16 meteorology with NACC to directly drive CMAQ via interpolation is feasible and yields reasonable results compared to the commonly used WRF approach.