HYDROTREND: A CLIMATE-DRIVEN HYDROLOGIC-TRANSPORT MODEL FOR PREDICTING DISCHARGE AND SEDIMENT LOAD TO LAKES OR OCEANS

HYDROTREND is an ANSI-standard FORTRAN-77 numerical model that creates synthetic river discharge time series as a function of climate trends. As a drainage basin simulator, the model provides simulation of daily discharge hydraulics at a river mouth, including the sediment load properties. Model outputs may provide direct input to lake or shelf circulation and sedimentation models. HYDROTREND accepts direct input from meteorological station data or global circulation model output (monthly statistics of temperature, precipitation and evaporation and their interannual variations), and input of basin characteristics (attitudinal temperature gradients, topography, glacier equilibrium line altitudes, and sediment transport and erosion coefficients). HYDROTREND applied to the temperate Eel River drainage basin provides a test of the model's handling of rare flood events brought on decadal, centennial or longer climatic events. The USGS observations on the Eel River include the decadal storms and the 400 y-return 1964 flood event. HYDROTREND captures the range in magnitude and return interval of peak discharge events and their sediment loads.