air quality assessment & management
Reference and User Manual
      AirWare   On-line Reference Manual
        Release Level 6.2
        Release Date 2013 09
        Revision Level 1.0
      Last modified on:   Monday, 9-Dec-13 10:32 CET

      Real-time scenarios

      For CAMx, AERMOD and PBM, real-time scenarios (daily forecast and hourly nowcasts) can be contructed. real-time scenarios can beconstructed.

      There are two possible real-time operations:

      1. Now-casting based on the most recent meteorological observations and air quality data for possible data assimilation;
      2. Fore-casting based on the most recent meteorolgical forecast, usually over 24 hours.
      For the real-time scenario, the input data for meteorology and emission are generated automatically, scheduled or event driven (availability of the necessray in put data), and the models are executed automatically, again schedules or even based.

      The results of a ral-time run are offered either as default result on dedicated results pages, or within the normal scenario selection.

      Configuration of scheduled runs

      The configuration of schedules runs consists of the following step:
      1. Select the corresponding scenario from the scenario list, or create a NEW scenario with the NEW button at that level; For CAMx, the main scenario for the master domain is mandatory, but the nested sub-domain scenario can be configured interactively;
      2. Edit the scenario (existing or new) to define
        • model domain (or nested sub-domain for CAMx);
        • pollutant;
        • emission scenario;
        • meteorological scenario.
      3. Editing the corresponding shellscript (see below, requires ADMIN privileges) to add the new scenario to the list of scheduled runs;
      4. optionally edit the crontab entry to modify the frequency of runs.
        Please note: all scenarios of the same type must run with the same temporal resolution, like every N hours.
      5. The number of CAMx subdomains for one scenario must not excced 9.
      6. The subdomains have to be square, and FIT to the 1 km master grid (origin on a master grid node, i.e., the coordinates in meter must end with 000 (see the CYPRUS domain definition in the MapSet), size is arbitrary.

      Editing the scenarios

      THe model scemarios consist of the following elements that can be interactively configured by the user:
      • selection of the model domain; the button DOMAIN leads to a listing of all domains available, including the option to generate a new one; viewing a domain also shows a button: SELECT to select the domain currently displayed;
      • selection of a pollutant (for CAMx AERMOD, and the associated chemical mechanism in CAMx, the list of applicable pollutants is defined in the systems knowledge base);
      • selection of a meteorological scenario; depending on the model and local configuration, this primarily involves selection of one (AERMOD) or several meteorological stations to be used for the meteorological input data time series; for CAMx, this can also include the option to use the MM5 meteorological fields rather than individual monitoring stations and the diagnostic wind model DWM.
      • Editing of the emission scenario. This is primarily derived from all the sources in the current model domain. However, the user can:
        • edit the multipliers for the classes: Boilers; Small stacks; Area Sources; and Line Sources subjecct to:
          • ADMIN user access rights;
          • the model not currently running.
        • switch on or off individual sources;
        • select or edit the temporal patterns associated with the individual source classes;
        • go to the emission inventory and edit the sources themselves.
          Please note: while the changes to a scenario are local to the scenarion, any changes to the inventory are SHRED by all models that do refer to the inventory: the on/off switch or a sectoral multiplier are scenario scpefic, but the basic emission rate is global and potentially shared !

      Editing the real-time shell scripts

      The scripts to drive the scheduled model runs are located on /var/www/cgi-bin in the respective model specific sub-directories. Below, the example shows the script for CAMx NOx nowcasts:
        # This file is used to run the camx forecast scenario for NOx
        # A new run is only started when the preceeding run is already finished
        # move error log from time to time
        if ( test `find /var/log/camx_NOxforecast.error -size +50k` )
            mv /var/log/camx_NOxforecast.error 
        date >> /var/log/camx_NOxforecast.error
        if ! test -e /var/www/cgi-bin/camx/runForecast.lck
             touch /var/www/cgi-bin/camx/runForecast.lck
             /var/www/cgi-bin/camx/camxmain.cgi -s 18534 -p 
             /var/cyprusair/camx/ -f /var/www/cgi-bin/db_config --forecast  1>
             /var/log/camx_NOxforecast.out 2>> /var/log/camx_NOxforecast.error
             rm -f /var/www/cgi-bin/camx/runForecast.lck
             echo "Forecast locked" >> /var/log/camx_NOxforecast.error
        exit 0

      editing crontab entries

      To trigger or execute the scripts at a given schedule, they are entered in the systems crontab; this can be done as user root with the command: crontab -e;

        #Scheduled Model Execution:
         1 * * * * sh /var/www/cgi-bin/aermod/
         1 0 * * * sh /var/www/cgi-bin/pbm/
        11 * * * * sh /var/www/cgi-bin/camx/
        21 * * * * sh /var/www/cgi-bin/camx/
        31 * * * * sh /var/www/cgi-bin/camx/
         5 2 * * * sh /var/www/cgi-bin/camx/
        15 2 * * * sh /var/www/cgi-bin/camx/
        45 4 * * * sh /var/www/cgi-bin/camx/
      For a description of the crontab syntax, please consult the serves on-line system manual with: man crontab.

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