PRZM Release Notes

This model is distributed by EPA as a legacy model, but no user support is available from EPA.

Version: 3.12.3

Corrections & Improvements to Prior Versions

  • Fixed foliar mass balance bug.
  • Added variable 'flitnum' (record 8).
    • Value of 'flitnum == 0' implies use of the przm 3.12.2 formulation of curve numbers.
    • Value of 'flitnum == 1' implies use of the Chow formulation of curve numbers.

Known Deficiencies

  • The parent/daughter routines do not function correctly. The production of daughter mass is miscalculated; however parent mass is correctly calculated.
  • Under certain conditions, consecutive Monte Carlo runs may not be initialized correctly. This issue is under investigation.
  • The variable IPIEND in Record 3 should only be set to 0, and pan evaporation should be read from the weather file. The Hamon option (IPIEND = 1 or 2) for determining evaporation is incorrectly coded in PRZM.
  • Pesticide associated with eroded solids is only removed from the top-most compartment. Changing the compartment size may result in dramatic changes to the pesticide mass removed by erosion.

Version: 3.12.2

Corrections & Improvements to Prior Versions

  • "Under canopy sprinkler irrigation" (IRTYP=4) no longer causes wash-off of pesticide. Water did not flow through the canopy and should not wash off pesticide.
  • Previously, water content was zero for the first day of the simulation. This caused irrigation to always occur on the first day of the simulation. To correct this, THETO now sets the initial soil water content.
  • Parameterization of wind speed improved.
  • Atmospheric stability functions of momentum and sensible heat, and the integrated momentum stability function parameterized in terms of the dimensionless .
  • Green-Ampt model (Infiltration volume) is solved explicitly using the Lambert W function.

Known Deficiencies

  • The parent/daughter routines do not function correctly. The production of daughter mass is miscalculated; however parent mass is correctly calculated.
  • Under certain conditions, consecutive Monte Carlo runs may not be initialized correctly. This issue is under investigation.
  • The variable IPIEND in Record 3 should only be set to 0, and pan evaporation should be read from the weather file. The Hamon option (IPIEND = 1 or 2) for determining evaporation is incorrectly coded in PRZM.
  • Pesticide associated with eroded solids is only removed from the top-most compartment. Changing the compartment size may result in dramatic changes to the pesticide mass removed by erosion.
  • The following deficiencies will be fixed in the next version:
    • Curve number functions CN1 and CN3 not defined for CN2 < 11.
    • The determination of the crop conditions active between the start of the simulation and the first emergence date fails.
    • "Array out of bounds" message for DelX.

Version: 3.12.1

Corrections & Improvements to Prior Versions

  • Repaired bug in irrigation routine.
  • The output file now reports how much irrigation is applied.
  • In PRZM 3.12 beta, irrigation was a function of the moisture deficit over the maximum root zone. In PRZM 3.12.1 only the active rooting zone is considered.

Known Deficiencies

  • Under certain conditions, consecutive Monte Carlo runs may not be initialized correctly. This issue is under investigation.

Version: 3.12

Corrections & Improvements to Prior Versions

  • Repaired bug in irrigation routine.
  • Enhanced irrigation options to allow irrigation without creating runoff.
  • Added CAM 9 and CAM 10 (see manual).
  • Documented error message 2170 (see manual).
  • Added ability to enter up to 32 curve numbers.
  • Corrected algorithms for production of metabolites to mirror approach in EXAMS, i.e., metabolites are produced as a mass fraction of degradation by phase.
  • Added output routines to support Express shell.
  • Added new warning message 2170: if CAM == 1, 2, or 3 and the soil incorporation depth (DEPI) is not equal to 4 cm, then
    • set DEPI equal to 4 cm.
    • issue warning message 2180. Table 11-1 (file CHAP11.PDF) modified accordingly. Execution continues.
  • Added new warning message 2180: if CAM == 4-10 and DEPI < DPN(1) then set DEPI to DPN(1) and issue message 2190. Execution continues.
  • Range check: incorrect values of CAM will be detected (error message 2200) and execution halted.
  • Manual has been updated appropriately.
  • Temperature bug fixed.
  • Because ANSI.SYS is not available for Windows 2000 and XP, ANSI control sequences have been removed.

Known Deficiencies

  • Under certain conditions, consecutive Monte Carlo runs may not be initialized correctly. This issue is under investigation.

Version: 3.12 Beta

Corrections & Improvements to Prior Versions

  • Recompiled and rebuilt all AIDE library (binary) files (WDM, ADWDM, UTIL) for version 3.0x using Lahey FORTRAN 32-bit, protected mode compiler, and Phar-lap linker version 5.01.
  • Created or updated PRZM model system and user support documentation files (READ.ME, RELEASE.TXT, UPDATE.TXT, ABSTRACT.TXT, RESPONSE.TXT).
  • Updated INSTALIT/MediaBuilder code and logic for product version description (.PVD) and installation (.INF) script files. Implemented numerous code changes to correct minor problems and add features/enhancements.
  • Updated Lahey FORTRAN MAKE utility (MAKEFILE) or DOS batch command file(s) for the AIDE library FORTRAN source code group files, and the PRZM model system FORTRAN source code.
  • Recompiled and relinked executable task image program file for the PRZM model, version 3.12 Beta, using Lahey FORTRAN 32-bit, protected mode compiler and Phar-lap linker.
  • Included new executable task image file (XPRZM3X.EXE) and updated run time support programs and files.
  • Included updated test output data files within the OUTPUT sub-directory to test the installation of the PRZM model.
  • Modified and updated the following PRZM run time support programs and files: PRZM.BAT (PRZM model execution DOS command file) and PRZMOPEN.SCR (PRZM model welcome screen file).
  • Application revisions to the PRZM model system, version 3.12 Beta, are included in the file UPDATE.TXT (PRZM Model System Update Notes). This document is available as an ASCII text (non-binary) file in the README sub-directory. Refer to file READ.ME in the README sub-directory for further information on the storage format and/or print/view requirements of this file.
  • Included application users' manual "PRZM-3, A Model for Predicting Pesticide and Nitrogen Fate in the Crop Root and Unsaturated Soil Zones: Users Manual for Release 3.0". This document is available as WordPerfect (version 6.1) documents in (binary, non-ASCII) files INTRO.WPD, CHAP1.WPD, CHAP2.WPD, CHAP3.WPD, CHPT4.WPD, CHAP5.WPD, CHPT6.WPD, CHAP7.WPD, CHAP8.WPD, CHAP9.WPD, CHAP10.WPD, and CHAP11.WPD within the DOCUMENT sub-directory. Refer to file READ.ME in the README sub-directory for further information on the storage format and hardware and/or software print/view requirement(s) of the user's manual files.
  • Users of PRZM2--versions 2.00 or 2.01 Beta as released and distributed through CEAM--should be aware that PRZM2 input files (e.g., .RUN, .INP, etc.) are not compatible with PRZM3 version 3.12 Beta also released and distributed through CEAM. The user is encouraged to refer to the PRZM3 User's Manual for additional examples and information concerning the content and storage format of PRZM3 input files (refer to item 10 above, file CHAP4.WPD).
  • Added nutrient algorithms to simulate agricultural application of nitrogen.
  • Added non-uniform mixing model for chemical application and subsequent extraction of runoff.
  • Added new features/enhancements as follows:
    • Nutrient algorithms to simulate agricultural application of nitrogen.
    • Non uniform mixing model for chemical application and subsequent extraction of runoff.
    • Calculation of peak flow as function of time of concentration.
    • Assignment of regional/seasonal storm event distributions to daily precipitation records.
    • Three sediment erosion modules: MUSS, MUST, and MUSLE.
    • Bi-phase degradation and transformation.
    • Transformation of metabolites in solid phase.
    • Correction of exponential decay term.
    • Each pesticide application and each chemical can have a different CAM.
    • User defined application efficiency.
    • Farm flag to prevent application on days with precipitation.
    • Temporal changes can be made to CN, USLE, C and Manning N.
    • Number of compartments allowed increased from 200 to 500.
    • Number of applications allowed increased from 200 to 800.
    • Availability of total, dissolved, gas, and sorbed phase concentrations in time series output file.
    • Ability to output averages and totals of time series variables over specified depth increments.
    • Ability to output averages depth-weighted soil pore-water concentrations.
    • Ability to output center of mass and maximum incursion available as time series output for leaching evaluations.
    • Metabolite transfer to EXAMSII model.
    • Ability to specify drift load as transfer to EXAMS II model.
    • Transformation of chemical on foliage.
    • Temperature dependent degradation.
  • Enhanced/expanded chemical application methods (CAM replaces FAM):
    • Surface application to soil with linear decrease with depth to 4cm.
    • Foliar application with linear soil interception.
    • Foliar application with exponential filtration.
    • Rototilling: uniform residue distribution to user defined depth.
    • Furrow: application of residue linearly with increasing depth to 4cm.
    • Incorporation: residue linearly decreasing with to user defined depth.
    • T-Band: user defined incorporation depth.
    • Shank injection: user defined incorporation depth.

Version: 2.3

Corrections & Improvements to Prior Versions

  • Implementation of FAM. Refer to PRZM23.PDF for more information.

Version: 2.01 Beta

Corrections & Improvements to Prior Versions

  • Updated and modified file RELEASE.TXT.
  • Recompiled and rebuilt AIDE library (binary) files (WDM, UTIL, and ADWDM) from version 3.0x using Lahey FORTRAN 32-bit, protected mode compiler and Phar-lap linker.
  • Implemented FORTRAN source code changes to correct minor errors and/or problems that occurred during model execution and added new features/enhancements as follows:
    • Date: Monday, 14 November 1994. Time: 15:41:06. Increased the number of pesticide applications from 400 to 600.
    • Date: Tuesday, 1 August 1995. Time: 13:06:21. Modified and corrected an input routine that reads an optional "special actions" command option within the special action line/field in a user specified PRZM2 input file (e.g., PRZM2.INP). The user specified input file is named by the user within the PRZM2 Run Time Supervisor file (PRZM2.RUN). With previous releases (version 2.00 and earlier) the user was required to left justify the special actions command option within an 8 character special action field. The following is an example line from a user specified PRZM2 input file. The special actions option "KD" is left justified in the 8 character input field as required with version 2.00 and earlier releases. For an example refer to the READ.ME file distributed with the model package. In the latest release (version 2.01 Beta), the user can enter a special actions option within a PRZM2 input file special action field either left justified, right justified, or at any point in between. For examples that are valid with version 2.01 Beta refer to the READ.ME file. The user should consult the PRZM2 User Manual (Version 2.00) file (USERSMAN.DOC) for valid Special Actions commands and command line options and their application in the PRZM2 model system.
  • Recompiled and relinked PRZM2 model using Lahey FORTRAN 32-bit, protected mode compiler, Phar-lap linker, and AIDE libraries listed above.
  • Included new executable task image file (XPRZM2X.EXE).

Version: 2.00

Corrections & Improvements to Prior Versions

  • Updated, added, and/or modified files RELEASE.TXT, UPDATE.TXT, and READ.ME.
  • Composed new INSTALIT/MediaBuilder code and logic. Upgraded INSTALIT/MediaBuilder product version description and INF script files from version 3.19c to version 5.03d. Implemented numerous code changes to correct minor problems and add features/enhancements.
  • Recompiled and relinked PRZM2 model using Lahey FORTRAN 32-bit, protected mode compiler, Phar-lap linker, and AIDE WDM, UTIL, and ADWDM libraries. Eliminated the need for Interacter graphics libraries during the PRZM2 model link step. Updated, recompiled, and rebuilt all AIDE library (binary) files (*.LIB) from version 2.0x to version 3.0x.
  • Replaced compile and link DOS batch command files with Lahey make files for the PRZM2 model and the PRZM2/HSPF and PRZM2/WASP programs.
  • Included new executable task image file (*.EXE) and all updated run time support programs and files to include FORTRAN source code for the PRZM2 model system version 2.00.
  • Implemented numerous FORTRAN source code changes to correct minor errors and/or problems that occurred during program and/or model execution and added new features/enhancements. For further information, refer to the addendum user's manual file, PRZDOCAD.DOC.
  • Compiled and linked the PRZM2 to HSPF and PRZM2 to WASP bridge (linkage) programs using Lahey FORTRAN 32-bit protected mode compiler, Phar-lap linker, and AIDE library (*.LIB) files.
  • Added PRZM2 to HSPF and PRZM2 to WASP bridge (linkage) program executable task image files (*.EXE) and all updated run time support programs and files to include test input and output data, and FORTRAN source code files for each program.
  • Added "Model Enhancements and Description of Bridge Programs for PRZM-2/HSPF and PRZM2/WASP Applications--Addendum to the Users Manual for Release 2.0 of the PRZM-2 Model" documentation file in WordPerfect (binary) format. For further information, refer to the addendum user's manual file, PRZDOCAD.DOC. Donigian, A.S., Jr., R.F. Carsel, J.C. Imhoff, and P.R. Hummel. 1994. Model Enhancements and Description of Bridge Programs for PRZM-2/HSPF and PRZM2/WASP Applications--Addendum to the Users Manual for Release 2.0 of the PRZM-2 Model. U.S. Environmental Protection Agency, Athens GA. (In Preparation).

Version: 1.02

Corrections & Improvements to Prior Versions

  • Modified INSTALIT/MediaBuilder PRZM2.PVD and PRZM2.INF file code and logic for the release and installation of version 1.02.
  • READ.ME: Updated and modified for release of version 1.02.
  • USERSMAN.DOC: Replaced all user manual *.WP WordPerfect files with this file. This is the final release of the user's manual with all figures.
  • PRZM2.RUN: Modified file to include documentation and instruction for the execution of PRZM2 MONTE CARLO simulation using input data files MC.INP, PRZM3.INP, and VADF3.INP.
  • PRZM2.EXE: New executable task image file.
  • PESTAP.FOR: Modified FORTRAN source code file where pesticide application is weighted by compartment size. Change included within file PRZM2.EXE. Modification transparent to user.
  • INITEM.FOR, PRZECH.FOR, PRZM2.FOR: Files that display version number and release date. Updated for release of version 1.02. Changes included within file PRZM2.EXE.
  • MET.INP: Deleted all 1981 records as data was incomplete. All test data sets distributed with model system execute correctly with this file.
  • MC.INP: MONTE CARLO test input file added. It can be used in conjunction with test input files PRZM3.INP and VADF3.INP. Refer to PRZM2.RUN file for further information.

Version: 1.01

Corrections & Improvements to Prior Versions

  • Updated and modified READ.ME file for release of version 1.01.
  • Upgraded and replaced INSTALIT/MediaBuilder code and logic version 2.68/P with version 3.19/C.
  • Increased the number of pesticide applications from 50 to 400. This allows the user to simulate multiple applications per year for an extended number of years. Increased the number of compartments in PRZM from 100 to 200 and in VADOFT from 100 to 400. This allows the user more flexibility with regard to soil profile depth.

Version: 1.00

Corrections & Improvements to Prior Versions

  • First release: October 1992.

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