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Environmental Modeling Community of Practice

BASINS Climate Assessment Tool Tutorials

The BASINS Climate Assessment Tool (CAT) provides a flexible set of capabilities for exploring the potential effects of climate change on streamflow and water quality using different watershed models in BASINS. Tools have been integrated into the BASINS system allowing users to create climate change scenarios by applying change factors to modify historical daily/hourly weather data. These data are then available as meteorological input to different BASINS watershed models. BASINS CAT version 1 was released with BASINS 4 in 2006 and was available for use only with the Hydrologic Simulation Program—FORTRAN (HSPF). BASINS CAT version 2 was released in 2013 with BASINS 4.1 and extends CAT capabilities to the Soil and Water Assessment Tool (SWAT) and Stormwater Management Model (SWMM) in BASINS. Minor cosmetic changes to the BASINS CAT interface were also implemented in version 2, and additional endpoints added that can be calculated based on model output.

For more information about BASINS CAT, the User’s Manual released with BASINS CAT version 1 provides technical information including a discussion of tool capabilities and a set of tutorials to support BASINS users interested in applying the CAT tool (BASINS 4.0 Climate Assessment Tool (CAT): Supporting Documentation and User's Manual (Final Report);

A more recent EPA report presents a series of short case studies using BASINS CAT version 2. Case studies in this report are designed to illustrate the flexible capabilities of BASINS CAT for conducting scenario-based assessments and sensitivity studies using the HSPF, SWAT, and SWMM models in BASINS (BASINS and WEPP Climate Assessment Tools (CAT): Case Study Guide to Potential Applications (Final Report;

EPA has also developed a series of lectures and exercises for BASINS CAT version 1. The lectures and exercises listed in the table below provide a case study example of how to apply the features of the CAT to a BASINS project

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