Using RIST to Convert Rainfall Records into Erosion Model Inputs |
Seth Dabney and D. C. Eagles | |
Introduction: Time-and-date-stamp data loggers provide better rainfall intensity data than do fixed-interval dataloggers because memory is not filled during periods without rain, yet short intervals between tips are recorded. Two of these loggers record precipitation data from tipping-bucket gages at the Little Topashaw Creek project. However, efficiency of data storage by such loggers is offset by having records that are not of uniform or predictable length. We developed RIST to summarize rainfall data and to convert that data into formats useful for several erosion and water-quality prediction models currently supported by the USDA-Agricultural Research Service(ARS). The current version of RIST is available as a free download from: | |
Standard outputs:for RUSLE include a storm-by-storm summary of total precipation, kinetic energy, and maximum 30-minute intensity; monthly rainfall; and bi-weekly El distribution. Options include omission of small storms, definition of storm break criteria, and selection between two kinetic energy equations. Output example:RIST was used to analyze a record of over 15,000 tips collected from 9/1/1999 through 10/23/2002 at Little Topashaw Creek. Computed 3-yr El distribution (right) matched that for Jackson, MS in the default RUSLE database within about 10% (observed annual R=480 vs. 440 for Jackson size=2>). |