Impacts of Max-Stable Process Areal Exceedance Calculations to Study Area Sampling Density, Surface Network Precipitation Gage Extent and Density, and Model Fitting Method

Max-stable process (MSP) models can be fit to data collected over a spatial domain estimate areal-based exceedances while accounting for dependence in extremes. They have theoretical grounding within the framework of extreme value theory (EVT). In this work, we MSP three-day duration cool season precipitation maxima Willamette River Basin (WRB) Oregon and 48 h mid-latitude cyclone annual Upper Trinity (TRB) Texas. total, 14 were (seven based on WRB seven TRB data). These model fits developed applied explore how user choices study area sampling density, gage extent, fitting method impact areal precipitation-frequency calculations. The impacts density also evaluated. development each involved application recently introduced trend surface modeling methodology. Significant reductions computing times achieved, with little loss accuracy, applying random sample subsets rather than entire grid when calculating Cougar dam WRB. Explorations extent revealed poor consistency among MSPs generalized (GEV) marginal distribution scale parameter. gauge robustness Regardless method, final GEV shape parameter estimates all fourteen greater their prescribed initial values which obtained from that assumed independence When two only differed by selected notable differences observed resulting