Greater flexibility introduced for defining Type 1 chemicals' partitioning properties:
any two of the three partition coefficients, octanol-water (KOW), octanol-air (KOA),
and air-water (KAW) can be entered to reflect the "three solubilities" approach.
Partitioning to aerosols is treated using either of two simple correlations with KOA.
For all chemical Types and all regions:
Wet aerosol deposition with either rain or snow is handled separately from dry deposition.
Sub-zero temperatures cause reduced evaporation and water runoff to mimic ice
formation.
Plant uptake is still treated as a single equilibrium process between the air and the lipid
in the plant. This approximation is regarded as a reasonable order of magnitude approach where all vegetation is to be treated as a single homogeneous secondary medium. However, the user is now given control of the mass percent of lipid present in the vegetation.
The estimation of chemical in terrestrial animals was removed as being too simplistic.
The calculations for groundwater and coastal water remained the same, however, the
variables are now accessible to the user.
Regional Properties:
A Country drop-down box has been added to the Regional Properties form to allow the user to select a country and then select the corresponding region. Only regions from that country are displayed in the region drop down box.
Inputs for Densities, Coastal Water Residence Time, and the Sorption Attenuation Factor have been added to the Regional Properties form to allow the user to control these values.
All of the properties of the region, including Transport Velocities, are entered on the
Regional Properties form rather than on a separate form. This will help to ensure that values specific to the region selected and those for a different region are not selected in error.
Layout
Changes were made to the layout of software components and additional information is
displayed.
The main window displays a schematic of the model with categories of Input properties on
the left and Output parameters and results on the right. A Compute button separates the two halves to distinguish clearly between the model input requirements and results. All input properties must selected by the user prior to the calculations being performed. None of the output parameters can be viewed until after the Compute button is pressed. The model schematic replaces the menu bar used previously.
The layout of information is now consistent between model windows, and with other models developed at the Canadian Environmental Modelling Centre.
Terminology has been updated to be consistent with recent work.
The calculations used in the ChemCAN model can be viewed, but not changed, by the user. This was not done in previous versions of the model.
The user is no longer required to supply an simulation identifier and additional comments but may choose to do so. Additional Description/Comments from the Print Simulation form has been added to the Simulation ID form to allow more descriptive information to be associated with the simulation.
A New Features button has been added to the About … form. This provides access to this information offline.
Help
Help files have been improved and expanded.
Error checking on the chemical and regional properties, and emissions has been improved
to avoid input errors.
Output
Model output has been improved.
The entire simulation data (input and results) can be saved to a file viewable by most common spreadsheet software.
All model output, whether viewed on screen, printed, or saved to a file, is identical except
that values in the file are not formatted. Numeric formatting rounds values to a size that is convenient to display. The user must identify the number of significant figures on any output value. The absence of formatting in the file allows the user to see the whole number calculated by the model without any rounding effects.
A date and time stamp was added to both the save-to-file and the printed output.
All printing is done from a single location. The user can choose to print the data tables (including all input values and results), and/or the summary diagrams.
All input values are italicized in the printed output making them readily identifiable. This will
facilitate the exact duplication of any given simulation.
For the intermedia transport half-times, water-to-air and soil-to-air the values for
air-to-water and air-to-soil were being displayed. This has been corrected.