NCEP Alaska Run Air Quality Forecast Change Log


 Alaska  Run Forecasts

 

Date

 Model Run

Change

2009-Present Developmental/Experimental/Operational Run Changes


ALASKA CMAQ RUN
    August 12, 2014                 12 UTC
         May 1, 2014                 00 UTC
October 18, 2011 12 UTC
  • The North American Model (NAM) was upgraded to the National Environmental Modeling System (NEMS) framework Non-hydrostatic Multi-scale Model (NMMB).  The NAM provides hourly meteorological predictions at 12 km to drive CMAQ.
          June 1, 2011                  00 UTC
July 6, 2010
12 UTC
  • Error found where particle Aitken number concentration became zero.  Correction to the post-processing made to handle zero values.
May 25, 2010
12 Z
   Implementation of NAM-CMAQ V4.6 Alaska NCO Experimental Forecasts
  • 48 hour forecasts at 06 and 12 UTC
  • 6 hour cycling at 18 and 00 UTC
  • 12 km CMAQ Lambert Conformal native horizontal grid
March 2, 2010
12 Z
More Realistic Alaska Emissions upgrades provided by NOAA/OAR/ARL:
1. Canadian anthropogenic emissions are processed and included in the new area and mobile emissions;
2. A new USGS-based land use file is prepared for PREMAQ;
3. New biogenic emission factor file (B3GRD) that allows BIES to calculate biogenic emissions from Alaska and three Canadian provinces;
4. A new OCEAN file for sea-salt emissions based on land use file and additional manual tuning for inland lakes;
5. An updated point source reflecting 2005 NEI and 2008 CEM data;
September 2, 2009
12 Z
 NAM-CMAQ V4.6 Alaska CB05-AERO-4 Daily AQF 48 hour model predictions begun.
  • Domain size: 200x164x22, Lambert Secant Conformal projection,
  • Corner points:
    • SW:52.945;-166.534
    • SE: 52.945;-130.666
    • NW:69.377;-179.822
    • NE: 69.377;-117.378
       
  • The CB05 chemical mechanism with more detailed Volatile Organic Compound (VOC) chemistry was implemented. 
  • A harmonized version of the AERO-4 aerosol chemistry mechanism was turned on. The harmonized NOx night time chemistry is configured with heterogeneous pathways turned off but gas-phase N205 hydrolysis turned on.  This was done to minimize the impact of aerosol chemistry on the ozone forecast.
  • Sea salt emissions were included in CMAQ.
  • Point, area and mobile emissions were upgraded based upon recent EPA National Emissions Inventory (NEI,  2005) and then projected for the current year. EGU sources use 2007 CEM data projected for 2009.  These emissions are also consistent with the CB05 chemical mechanism.
  • Biogenic Sources are currently set to Alaska land-use type surrogates for Canadian part of domain.
  • Lateral Boundary Conditions:  Running with static boundary conditions used for CONUS. Testing boundary conditions generated from  GEOS-5 -Chem global model


HAWAII CMAQ RUN
March 23, 2010
12 UTC
 NAM-CMAQ Hawaii CB05/AERO-4 predictions moved to NCO experimental run slot:
  • 48 hour forecasts at 06 and 12 UTC
  • 4x/day cycling
February 2, 2010
12Z  NAM-CMAQ Hawaii CB05-AERO-4 Daily AQF 48 hour model predictions begun:
  • Domain size: 80x52x22, Lambert Secant Conformal projection,
  • Corner points:
    • SW:17.61;-162.080078
    • SE: 17.609863;-152.914551
    • NW:23.325584;-162.25
    • NE: 23.325447;-152.744284
       
  • The CB05 chemical mechanism with more detailed Volatile Organic Compound (VOC) chemistry was implemented. 
  • A harmonized version of the AERO-4 aerosol chemistry mechanism was turned on. The harmonized NOx night time chemistry is configured with heterogeneous pathways turned off but gas-phase N205 hydrolysis turned on.  This was done to minimize the impact of aerosol chemistry on the ozone foreceast.
  • Sea salt emissions were included in CMAQ.
  • Point, area and mobile emissions were upgraded based upon recent EPA National Emissions Inventory (NEI,  2005) and then projected for the current year.  Point EGU sources use 2007 CEM data.  These emissions are also consistent with the CB05 chemical mechanism.  More detailed Hawaii emission information is described by Daniel Tong, ARL, here.
  • Lateral Boundary Conditions:  Running with climatologically averaged ozone from the Hilo ozonesonde site with GEOS5-Chem global model climatological precurser species.