Comprehensive Calibration of Hydrological Simulation Program: Phase 5 Insights
Phase 5 of the calibration project for the Hydrological Simulation Program - Fortran (HSPF) has yielded results that are consistent with previous calibrations in literature, notably improving over Phase 4. This phase involved advanced techniques for separating stormflow from baseflow and assessing water balance, leading to a better representation of seasonal changes. Key statistics were evaluated, including model efficiency and recession rates, indicating progress. While significant improvements have been made, a few areas still require attention, ensuring readiness for future sediment calibration.
Comprehensive Calibration of Hydrological Simulation Program: Phase 5 Insights
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Presentation Transcript
Hydrology Calibration Phase 5
Calibrators • USGS-MD • Jeff Raffensperger • Sarah Martucci • Joe Vrabel • Angelica Gutierrez • Gary Fisher
Calibrators • USGS-VA • Doug Moyer • Alan Simpson • Jen Krstolic • ICPRB • Ross Mandel • Julie Kiang
Calibrators • CBP • Sara Brandt • Jing Wu • Kate Hopkins • Lewis Linker • Gary Shenk
Status • Consistent with other HSPF calibrations in the literature • Better and more consistent overall than phase4 • Reaching point of diminishing returns
Strategy • Water Balance • Stormflow / Baseflow separation • Base Flow • Storm Flow • Seasonal Changes Adapted From: Users Manual for an Expert System (HSPEXP) for Calibration of the Hydrological Simulation Program—Fortran By Lumb, McCammon, and Kittle USGS-WRI Report
Statistics to judge overall calibration • Bias • Base / Storm separation • Recession rates • Model efficiency
Baseflow / Stormflow Stat Fraction of flow that is baseflow (simulated) Bstat = 1 - Fraction of flow that is baseflow (observed) baseflow / total flow (simulated) Bstat = 1 - baseflow / total flow (observed) stormflow / total flow (simulated) Qstat = 1 - stormflow / total flow (observed)
Baseflow / Stormflow Recession Statistic average Simulated recession index Q rec Index = 1 - average Observed recession index quick flow tomorrow ) Average Recession index = Average ( quick flow today
Nash – Sutcliffe Model efficiency (variance of errors) (variance of observed) Computed for daily, log of daily, and monthly values. 1 -
Reported values of N-S efficiency • Often reported, but little information on ‘standards’ of efficiency • Reported daily efficiencies 0.5 - 0.75 • Reported daily log efficiencies 0.5 - 0.75 • Reported monthly efficiencies 0.7 – 0.8
Reported values of N-S efficiency • Often reported, but little information on ‘standards’ of efficiency • Reported daily efficiencies 0.5 - 0.75 • Reported daily log efficiencies 0.5 - 0.75 • Reported Monthly efficiencies 0.7 – 0.8
Reported values of N-S efficiency • Often reported, but little information on ‘standards’ of efficiency • Reported daily efficiencies 0.5 - 0.75 • Reported daily log efficiencies 0.5 - 0.75 • Reported Monthly efficiencies 0.7 – 0.8
Where are we in relation to p4 • Better overall • More consistent parameterization • Calibrated at many more sites
Status • Consistent with other HSPF calibrations in the literature • Better and more consistent overall than phase4 • Reaching point of diminishing returns • Still a few small areas and issues that need attention in hydrology
Ready for Sediment? • River calibration cannot change significantly • Land calibration must have significant surface runoff
