The Canadian

Centre for Environmental Modelling and Chemistry

Level III Software Update

Version 2.80 - May 2004

Since the Version 2.70 (March, 2002) release:

Simulation ID
  • There is now an input box for additional notes which is then entered directly into the print simulation section and will appear on the final printout.
    Chemical Properties
  • There was an error in v. 2.70 which did not allow changes in the Chemical Properties and New Chemicals sections to be saved to the Database. This has been corrected and applies to all three types of Chemical.
  • There is a change to the half-life checkboxes. When the half-life checkbox is ticked so that the half-life is considered to be negligible and then the user enters a new half-life into the input box the check box is unchecked and the new value is stored.
  • In all input boxes on the Chemical Properties and New Chemical pages, when errors are caught the field in error is highlighted and cleared in order for the user to reenter an appropriate value.
  • The Henry’s Law Constant display has been removed from this form and is now only viewable in results. This was done to ensure a smoother run of the program. It will not affect the user’s results in any way.
    Environmental Properties
    There is an increased flexibility for defining Environments.
  • A water area of 0 m2 is now allowed. When this value is entered it will automatically change the water and sediment depths to 0 m.
  • The areas of soil and sediment are no longer displayed on this input form.
  • It is now impossible to enter a zero value for area or depth of air.
  • There are more Standard Environments to choose from. The single Default Environment has been replaced by Default 1, 2 and 3. Three additional environments are included as described below. The user is not permitted to change the properties of these environments in the database. - Default 1 is similar to the Default Environment in v. 2.70 except that the air residence time has been changed to reflect a more realistic value. - Default 2 is based on the Southern Ontario region defined in ChemCAN v 6.00. - Default 3 is similar to the Shield Lake Region. - Shield Lake Region (Mackay, D., Webster, E., Woodfine, D., Cahill, T., Doyle, P., Couillard, Y., Gutzman, D. 2003. Towards Consistent Evaluation of the Persistence of Organic, Inorganic and Metallic Substances. Human and Ecological Risk Assessment (HERA). 9: 1445-1474.) - EQC - standard environment (Mackay, D., Di Guardo, A., Paterson, S., Cowan, C.E. 1996. Evaluating the Environmental Fate of a Variety of Types of Chemicals Using the EQC Model. Environ. Toxicol. Chem. 15: 1627-1637.) - Beyer Environment (Beyer, A., Mackay, D., Matthies, M., Wania, F., Webster, E. 2000. Assessing Long-range Transport Potential of Persistent Organic Pollutants. Environ. Sci. Tech. 34: 699-703.) Additional entries in the database can be changed and are thus are the responsibility of the user.
  • There was an error in v. 2.70 which did not allow changes in the Environmental Properties and New Environments sections to be saved to the Database. This has been corrected.
  • Labeling on the Environmental Properties’ tabs is now consistent, where titles and units are given only where necessary. There has been to reduce redundancy and to ensure that all appropriate units are displayed.
  • It is now possible to enter a value of zero into any of the volume fraction boxes as long as the total value of the boxes is equal to one or another appropriate value.
  • There is now a Help Button on the New Environment Form.
  • There are no changes to this section.
    Chemical Parameters
  • There are no changes to this section.
    Environmental Parameters
  • There are no changes to this section.
  • The Advection tab has been corrected and now includes the air residence time as defined in Chemical Properties by the user.
  • The Results section has been corrected to correctly display the D-value units, and aquivalence units for Type 2 chemicals.
  • A more balanced and easy to follow look has been given to the Results section.
  • When the diagram is closed the user’s cursor now advances naturally onto the Charts button.
  • Bar charts are used for the fugacities, masses and concentrations in each medium. Pie charts are used for relative amounts in each medium.
    Error Checking
  • The error message for a user entering a value that is Outside Reasonable Bounds has been updated so that it now states “The absolute value of the exponent is too large. Please enter a reasonable value”.
  • On the Densities Tab in Environmental Properties the appropriate error message is now displayed when a zero value is entered.
  • Error checking has been corrected so that values larger than and smaller than the absolute value of 3e?38 are caught and the program does not crash.
  • Error checking has been corrected so that when the area of water > area of air the appropriate messages are displayed and corrections can be input.
  • Z-value calculations for Type 3 chemicals has been corrected so that it displays the correct values for pore water in sediment.
  • The option for printing the date and time when printing Tables has been corrected so that it works.
  • Note: All corrections to units and calculations in above sections have carried over to the printout.
    Help Files
  • The Environmental Properties Help File now contains a discussion of the database including source information.
  • The Environmental and Chemical Database Operations’ Help Files are now applicable to both types of operations.
  • The Results Help File now contains an updated definition of fugacity, consistent with Level III, steady-state non-equilibrium, concepts.
  • The About Button on the Main form has been altered so that it no longer includes the program’s name.
  • The New Features Button, which you have already used, is a New Feature to this program.

    Since the Version 2.65 (February 2002) release:

  • The chemical half-lives are now correctly saved to the database.
  • It is now possible to add new Type 2 and 3 chemicals using the "New Chemical" button.
  • The name of the environment is now displayed under the chemical name before printing the results.
  • Added Chart display of selected results. These can also be printed with the rest of the results.
  • Corrected the description of the save-to-file function in the general Help file.
  • Updated the Help file for the Print function.

    Since the Version 2.20 (December 1999) release:

  • The aerosol deposition velocity parameter is now entered as the dry deposition velocity and a scavenging ratio rather than as a combined wet and dry velocity.
  • Updated terminology to be consistent with recent work.
    Suspended sediment is now more correctly referred to as suspended particles and "pure air" is now referred to as air vapour.
    Molecular mass is now more correctly referred to as molar mass.
  • An over-sight in the numerical formatting routine was corrected.
  • Corrected model name in various Help files and in the readme.txt file.
  • Calculations now print correctly.
  • All model output, whether viewed on screen, printed, or saved to a file, are identical except that values in the file are not formatted. This allows the user to see the whole number calculated by the model without any rounding effects.
  • Removed irrelevent D value totals.
  • Improved error checking.
  • Incorrect information in the Help files for the Environmental Properties and Emissions input forms has been removed.

  • In the display of results, the layout of the chemical parameters was improved.
  • The aerosol-air partition coefficient is no longer displayed for Type 2 chemicals where it is not applicable.
  • A label error in display of Intermedia Transport was corrected. "Water to soil" is now "Soil to air".
  • Concentration (ug/g ) in sediment solids was wrongly displayed as the value for soil pore air.
  • Overall D values have been added to Results display.

  • Results are now saved to a comma separated value file making it more generally accessible to a variety of spreadsheet programs.
  • The units of Fugacity for Type 1 and 3 chemicals were corrected in the save-to-file output.
  • The save-to-file output was recording the sediment D value for reaction as that of soil. This has been corrected.
  • A listing of environment properties used were added to the save-to-file output.
  • A date and time stamp was added to save-to-file.
  • Layout of the save-to-file output was generally improved.

  • All input values are italicized in the printed output to facilitate future simulation duplication.
  • The layout of the printed output of chemical parameters was improved.
  • The aerosol-air partition coefficient is no longer printed for Type 2 chemicals where it is not applicable.
  • The aerosol-water partition coefficient is no longer printed for Type 1 where it is unnecessary and illogical.
  • The "Save Diagram" option was removed. It did not work consistently. The diagram can be captured using the "Print Screen" button on the keyboard, and pasted into a file to be saved. A note was added to the Help file for the Diagram to indicate this.

  • A date and time stamping option was added to the printed output.

    Special thanks to Jenn Brimacombe, Angela McLeod, Chris Warren and the WE512 class of 2001 for checking the model results.

    Since the Version 2.10 (September 1999) release:

  • The values displayed in the Diagram for concentration in soil and sediment have been corrected. Previously there was an error in the unit conversion.
  • The units listed for Fugacity in the Tables of Printed Results have been corrected.
  • The typographical error in the "note" about the air and water densities was corrected.

    Model Description

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    Last updated August 12, 2011.