AirWare
air quality assessment & management
Reference and User Manual
     
      AirWare   On-line Reference Manual
        Release Level 7.0
        Revision Level beta
        Release Date 2015 03

      Last modified on:   Monday, 13-Jul-15 19:27 CEST

      Time-variable emissions: emission patterns

      Emissions vary in time. To reflect that, AirWare supports three mechanisms:

      1. explicit editing of emission time series (e.g., for PBM, PUFF);
      2. use of time-series data of emissions (only for boilers/major stacks associated with industrial plants, including the optional PEMS modeling);
      3. use of temporal scaling factors.

      The temporal scaling factor can be specified for:

      • monthly variations, 12 values for seasonal variations;
      • day of the week, 7 values, for differences between workdays and weekends;
      • hourly variations, 24 values, for daily patterns such as working hours or rushour.

      The values (multipliers) can be normalized (BUTTON: NORMALIZE) so that their toal effect is neutral or mass conservative over a full year, when applied to the annual average value at an hourly basis.

      The temporal patterns can be assigned to

      • individual emission sources
      • classes of emission sources (by sector) at the level of model specific emission scenarios.

      Examples from the emission source subtypes and the sectors for the allocation of class level patterns, directly from the data base, are shown below:

      mysql> select * from AIR.CLASS_TO_EMISSION_SECTOR;

      CLASSIDCLASS_SUBTYPE EMISSION
      SECTOR_ID
      60Boiler1
      60Central Heating4
      60Hotels3
      61Airports0
      61Dry Cleaners2
      61Petrol Stations2
      61Residential Areas4
      54NULL1

      mysql> select * from AIR.EMISSION_SECTOR;

      ID NAME
      1 Industrial
      2 Commercial
      3 Touristic
      4 Residential
      5 Traffic

      Assigning patterns to emission sources

      • CAMx:
        • LINES: individual line sources do not have TS nor pattern, they always use pattern defined for sector "Traffic"
        • BOILERS: uses Boiler TS (if available), otherwise source pattern, otherwise pattern defined for sector "Industrial"
        • SMALL STACKS and AREA sources: do not have TS, use source pattern, otherwise pattern of the sector assigned to the type/category of the source. In case no type/category is defined for the source it uses pattern "Neutral"
      • AERMOD:
        • LINES: do not have TS nor pattern, always use pattern defined for sector "Traffic"
        • BOILERS: does NOT yet use Boiler TS, uses source pattern, otherwise pattern defined for sector "Industrial"
        • SMALL STACKS: use source pattern, otherwise pattern defined for sector "Commercial"
        • AREA sources: do not have TS, use source pattern, otherwise pattern of the sector assigned to the type/category of the source. In case no type/category is defined for the source it uses pattern "Neutral"

        CAMx and AERMOD differ:

        • BOILERS: CAMx uses TS if available, AERMOD not
        • SMALL STACKS: CAMx uses pattern of the sector assigned to the type/category of the source, AERMOD uses always pattern of sector "Commercial"

      Editing Emission Patterns

      Emission patterns are an OBJECT CLASS, accessible via the DataBase icon from the main menu. They can be selected by name, or a new pattern can be generated (and named) using the New button; an empty TEMPLATE is generated. Tho edit, enter a name, and save to generate that OBJECT.

      The TEMPLATE can then be used to enter "arbitrary" multipliers that represent the relative emission strength by month, day of the week, and hour of the day. The normalize" the pattern, use the button: "normalize", that will guarantee that the average multiplier is one (mass conservative).

      Exceptions: public holidays

      A list of statutory holidays with their associated emission reduction (or more general: correction) factors is available as a special object class.

      Pattern for real-time scenarios

      Selecting temporal emission patterns for CAMx forecast scenarios can only be done by members of group 'admin':

      • At the forecast scenario page: select the main model domain - this is the domain with the largest extent and includes all other domains. Click button "Emission".
      • At the emission scenario page: click button "Temporal Pattern" and select the pattern.
      Warning: Currently the forecast scenarios are independent for each day. Therefore the selection of pattern is only valid for one day of forecast. To apply a pattern to the complete sequence of forecast scenarios, each of the individual forecast scenarios needs to be edited.


© Copyright 1995-2016 by:   ESS   Environmental Software and Services GmbH AUSTRIA | print page