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CALMIM

    The California Landfill Methane Inventory Model is a 1-dimensional soil gas transport and oxidation model that calculates annual landfill methane emissions based on the cover soil characteristics and annual climatic data for a given global location.

    WeedCast Version 4

      The WeedCast Software Suite is a decision aid that currently includes the WeedCast and WheatScout models. These models were created by the USDA ARS and the University of Wisconsin. The software is written in Java and is free to download and use. The source code is released under the GPL.

      SolarCalQ - Version 1

        The purpose of the SolarCalQ Version 1 JAVA model is to simulate the spectral quality of incident solar radiation for any location on the globe, down to one minute time steps.

        Nitrogen Decision Aid

          The Nitrogen Decision Aid is a computerized program that predicts the amount of N mineralized from planting to side-dress or 5-leaf growth-stage. By applying just enough N-fertilizer to reach the critical soil nitrate concentration it is possible reduce this waste. This model is designed for Northern climates that will have some frost in the soil during the winter.

          Sorption Isotherm Spreadsheet

            Spreadsheet from the paper entitled: On the Use of Linearized Langmuir Equations by C.H. Bolster and G.M. Hornberger, Soil Science Society of America Journal, 2007, 71(6): 1796-1806.

            Modified Langmuir Equation Spreadsheet

              Spreadsheet from the paper entitled: Revisiting a Statistical Shortcoming when Fitting the Langmuir Model to Sorption Data by C.H. Bolster, Journal of Environmental Quality, 2008, 37:1986-1992. Spreadsheet has been modified to make a correction to the calculation of E for weighted data. (3/18/2010).

              The Ogallala Agro-Climate Tool

                The Ogallala Agro-Climate Tool is a Visual Basic application that estimates irrigation demand and crop water use over the Ogallala Aquifer region.

                Cotton Irrigation Tool

                  A Web Application for Estimating Irrigated and Dryland Cotton Profitability using Modeled Yield Data.

                  Bushland ET Calculator

                    The Bushland Reference ET calculator was developed at the USDA-ARS Conservation and Production Research Laboratory, Bushland, Texas. Although it was designed and developed for use mainly by producers and crop consultants to manage irrigation scheduling, it can also be used in educational training, research, and other practical application. It uses the ASCE Standardized Reference Evapotranspiration (ET) Equation for calculating grass and alfalfa reference ET at hourly and daily time steps. This program uses the more complex equation for estimating clear-sky solar radiation provided in Appendix D of the ASCE-EWRI ET Manual. Users have the option of using single set or time series weather data to calculate reference ET. Daily reference ET can be calculated either by summing the hourly ET values for a given day or by using averages of the climatic data.