Century5 Reference
Document Revision History

Date Description
10 Jun 99 Draft version 1.
16 Nov 99 Draft version 2.
May 2000 Draft version 3.
Added the Font, Previous TOC topic, and Next TOC topic buttons to the Microsoft Windows HTML Help toolbar.
Added most of the remaining Century 4 manual describing the Century model.
Added the following pages: glossary; management events; site parameters (climate, soil, external nutrients, crop SOM, forest SOM, mineral NPS, soil water); model parameters (crop, cult, fert, fire, fix, graz, harv, omad, tree, trem); weather data file; Century error messages; site parameter editor; literature cited; units; limits.
Reorganized the table of contents.
Added an index to the Microsoft Windows HTML Help compiled help file.
June 2000 Draft version 4.
Added more hypertext links to various sections.
Added more description to the soil submodel.
Added appendix for output variables.
Feb 2001 Draft version 5.
Misc. editing.
Updated description of erosion and deposition algorithms, and output variables.
March 2001 Draft version 6.
Added pages for (1) the layered soil submodel, and (2) the submodel for the depth distribution of organic C.
November 2001 Draft version 7.
Moved the page "Century Version 5 Release Notes" to the main level table of contents so it can easily be found.
Misc. editing of several pages.
Expanded the Running with Command-Line Options page.
Updated the Specifying Preferences page to reflect the new command-line options.
Updated the following pages: Crop and Grass Submodel, Nitrogen Submodel, Running the Century Simulation, Troubleshooting Your Simulation Configuration, Erosion File.
Updated the version release notes.
December 2001 Draft version 8.
Updated the following pages: Implementation of an Algorithm for a Layered Soil Submodel, Exponential Depth Distribution of Organic Carbon, Site Parameters for Soil and Physical Controls, Plant Production Submodels: Overview, Soil Organic Matter Submodel, Nitrogen Output Variables, Phosphorus Output Variables, Phosphorus Submodel, Sulfur Submodel, Sulfur Output Variables, Erosion File, Site Parameters for Initial Mineral N, P, and S.
Updated the version release notes; the structure of the document has been enhanced to clarify information about changes to each release.
Dec 2002 Draft version 9.
Updated pages for the N submodel, site parameters, "Units Used in Century", and "Running with Command-Line Options". Several other pages had minor changes.
July 2003 Updated and enhanced the description of the water submodel.
Nov 2004 Updated the following pages: Fixed Parameters, Grassland/Crop Submodel.
Jan 2005 Added pages for DayCent5 site parameters: Hydrology and Biophysical Controls; Soil Temperature.
Modified pages: Editing Site Parameters, Site Parameters for Soil and Physical Controls.
Feb 2005 Modified pages: Running Century and CMI with Command-Line Options, Preparing for a Century Simulation, Editing Site Management, Editing Site Parameters.
April 2005 Modified pages: Nitrogen Submodel; Crop and Grassland Submodel; Forest Submodel; Fertilizer Additions; Nitrogen Output Variables; Water and Temperature Output Variables; Site Parameters for Soil and Physical Controls.
May-June 2005 Modified pages: Utilities for the Century5 Model; Crop and Grassland C Output Variables; Nitrogen Output Variables; Phosphorus Output Variables; Sulfur Output Variables; Fixed Parameters; Soil Organic Matter Submodel; Water Budget, Leaching and Soil Temperature; Fire; Running Century and CMI with Command-Line Options.
August 2005 Modified pages: Tree Removal Parameters ; Forest Submodel ; Fixed Parameters ; List of Figures .
October 2005

Added pages: Running a Century Simulation to Equilibrium; Site Parameters Validation; DayCent5
Modified pages: Running Century and CMI with Command-Line Options

April 2007 Expanded DayCent5 trace gas submodel page. Added output variable table to maintenance respiration page. Added output variable table to soil water submodel page.
May 2007 Clarified several of the tree parameters (tree.100 file).
August 2007 Further editing of tree, crop, and fixed parameter descriptions. Update pages for Fire and Crop/Grass Fire Parameters.
April 2008 Updated the page describing the DayCent5 soil hydrology submodel. Clarified evaporation algorithm. Modified other text to match the current model algorithms.
Feb 2009 Corrected descriptions of fixed parameters OMLECH(3) and MINLCH so as to distinguish between monthly and daily models' values.
Added missing descriptions of NEE and NBP output variables to the Foreset C page.
Updated Utilities: added Century5.R.
March 2009 Added output variables NEEA and NBPA to the Forest C page. Clarified the description of the FERTOT(*) output variables.
August 2010 Updated the pages: welcome, copyright, contact-nrel, index, top, bottom, left-frame.
Added the image file Daycent5_Flows.png.
Nov 2010 Updated the pages: Savanna Submodel; Tree Parameters.
May 2011 Added page: C5MPI.
Added graph: Factor for N Availability to Grasses In Savanna.
Modified the page on the Forest submodel to clarify LAI parameters.
Modified the page on the Savanna submodel to include a link to the new graph.
June 2011 Moved descriptions of the fixed parameters PPRPTS(*) to the obsolete fixed parameters page.
Updated the crop submodel page to describe the new algorithm for the soil water effect upon production. Added a figure to show the curve.
Added page Monthly Weather Data in a NetCDF File.
Sep 2013 Added pages Site Parameters: netCDF file, Site Parameters: Spatial netCDf file, Soils NetCDF file.
Modified pages site.100 file, Site Parameters, Utilities.
May 2014 Modified pages regarding IDEF parameter: Soil Organic Matter Submodel, Fixed Parameters.
Fixed parameters TEFF: Added a graph showing the behavior of the Century5 and DayCent5 functions for the temperature effect on decomposition.
Nov 2014 Modified pages Fertilizer Additions, Crop and Grassland Submodel.
Jan 2015 Modified pages to contain a description of new output variables EFERT(*): Fertilizer Additions, and the N, P, S Output Variable pages.
Mar-June 2015 Modified the page Century Model Parameters to describe how create and use custom parameter sets.
Updated the page Preparing for a Century Simulation.
Added new appendix page Building and using the models in the Cygwin environment.
Rearranged the order of the appendices.
Modified the display of the Users Guide menu and start page for a less cluttered look.
Modified the page Weather Data to better describe the possible locations of weather data files.
Modified the page Fixed Parameters to show a list of fixed parameter files provided in the model distribution.
Modified the page Management Blocks: reorganized text and added new keywords for certain fields.
Updated pages: Preparing for a Simulation, Running a Simulation, Files and Directories, Examining Simulation Results, Management Events, Utilities, C5MPI.
Oct 2018 Site parameter tables: added CSS-specified formatting.