Assessing Streamflow and Sediment Loading Response to Storm Events in Apalachicola River under Climate and Land Cover Change

Abstract:

This study examines response of streamflow and sediment discharge in the Apalachicola River, Florida under storm events with return period of 25-year and duration of 24-hour under projected climate change and land use land cover (LULC) change. A hydrologic model using the Soil Water Assessment Tool (SWAT) was developed for the Apalachicola region to simulate discharge and sediment load under present (circa 2000) and future conditions (circa 2100). LARS-WG stochastic weather generator is utilized to temporally downscale temperature and precipitation projections from four Global Climate Models (GCM) under three carbon emission scenarios for A1B, A2, and B1. The projected 2100 LULC data obtained from the United States Geological Survey (USGS) EROS Center are correspondingly associated with each emission scenarios. The LULC only and coupled climate / LULC impacts on streamflow and sediment are assessed for the storm events. Results from this study are coupled to a hydro-marsh and then sediment transport model for the Apalachicola bay to further assess ecological effects of coupled sea level rise and terrestrial change.