For more information on the USGS-the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment-visit http://www.usgs.gov or call 1-888-ASK-USGS.For an overview of USGS information products, including maps, imagery, and publications, visit http://store.usgs.gov.Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner.Suggested citation: Webb, R.M.T., and Parkhurst, D.L., 2017, Water, Energy, and Biogeochemical Model (WEBMOD), user's manual, version 1: U.S. Geological Survey Techniques and Methods, book 6, chap. B35, 171 p., https://doi.org/10.3133/tm6B35. ISSN 2328-7055 (online) iii Preface This report describes the U.S. Geological Survey Water, Energy, and Biogeochemical Model. The performance of the program has been tested in a variety of applications. Future applications, however, might reveal errors that were not detected in the test simulations. Users are requested to send notification of any errors found in this report or the model program to:Office of Surface Water U.S. Geological Survey 411 National Center Reston, VA 20192 (703) The latest version of the model program and this report can be obtained using the Internet at address https://doi.org/10.5066/F7P26W9K.
Conversion FactorsInch/Pound to International System of Units
MultiplyBy Altitude, as used in this report, refers to distance above the vertical datum. The vertical datum is usually mean sea level with altitude expressed as meters above mean sea level (mamsl) A water year is the 12-month period beginning October 1 for any given year through September 30 of the following year. The water year is designated by the calendar year in which it ends.
Supplemental InformationResults for measurements of stable isotopes of an element in water, solids, and dissolved constituents commonly are expressed as the relative difference in R sample , the ratio of the number of the less abundant isotope to the number of the more abundant isotope measured for a sample, with respect to R standard , the same ratio in a measurement standard. This ratio of ratios is greater than 1.0 when the sample contains a greater proportion of the less abundant isotope than proportion measured in the standard, and less than 1.0 for the converse situation. The relative abundance of the light isotope is commonly expressed as delta, δ = (R sample /R standard -1)1000, in parts per thousand (‰).
Formatting ConventionsThe Modular Modeling System (MMS) represents Earth-system processes in modules that share parameters, variables, and dimensions. Parameters are user-specified values that do not change during a simulation. Variables are simulation states and fluxes that can vary with each time step. Dimensions define the array sizes of ...