Per la serie di seminari in meteorologia ambientale dell’Università di Trento, giovedì 9 maggio 2024 alle ore 17:30, Paolo Reggiani, del Department of Civil Engineering, Research Institute for Water andEnvironment dell’Università di Siegen (Germania), terrà un seminario dal titolo: A retrospective hydrological uncertainty analysis using precipitation estimation ensembles for the poorly gauged Upper Brahmaputra Basin. Il seminario si terrà in presenza nell’aula 1P (primo piano) del DICAM – Università di Trento, in via Masiano 77, e sarà possibile seguirlo in streaming su Zoom attraverso il seguente link: https://unitn.zoom.us/j/83986532497 Meeting ID: 8398653 2497, Passcode: 708707 AbstractWe study the impact of uncertain precipitation estimates on simulatedstreamflows for the poorly gauged Chinese Upper Brahmaputra Basin (UBB)in High Mountain Asia. The process-based hydrological model TOPKAPI at0.5 km resolution is driven by an ensemble of precipitation estimationproducts (PEPs), including analyzed ground observations, high-resolutionprecipitation estimates, climate data records and reanalyses over the2008-2015 control period. The model is then forced retrospectively from1983 onward to obtain seamless discharge estimates till 2007, a periodfor which there is very sparse flow data coverage in this part of thebasin. Whereas temperature forcing is considered deterministic,precipitation is sampled from the predictive distribution, which isobtained through processing PEPs by means of a probabilistic processorof uncertainty. The employed Bayesian processor combines the PEPs andoutputs the predictive densities of daily precipitation depthaccumulation as well as the probability of precipitation occurrence,from which random precipitation fields to force the hydrological modelare sampled. The predictive density of precipitation is conditional onthe precipitation estimation predictors that are bias-corrected andvariance adjusted. For the UBB, discharges simulated from reanalysis andclimate data records score lowest against observations at three flowgauging points, whereas high-resolution satellite estimates performbetter,but are still outperformed by precipitation fields obtained fromanalyzed observed precipitation and merged products, which we correctedagainst ground observations.The methodology employed in this hydrological study indicates howmissing flows for poorly gauged sites can be successfully retrieved. Themethod can be further extended for hydrological projections of climate.BioPaolo Reggiani holds the Chair of Water Resources Management and ClimateImpact Research at the University of Siegen, Germany. He graduated atthe University of Trento, Italy, in 1994 in Environmental Engineeringwith a Masters in Engineering. In 2000 he was awarded a Ph.D. with‘Distinction’ in Environmental Engineering from the University ofWestern Australia. Between 1999 and 2000 P. Reggiani worked at CSIROLand and Water in Floreat Park, WA, where he developed modelingapproaches to assess dryland salinity in Australia. After his return toEurope in late 2000 he participated as “Marie Curie Fellow” at thesoil science lab “Laboratoire des Transferts en Hydrologie etEnvironnement” (LTHE) in Grenoble, France. In 2002 he took up anappointment as researcher and scientific consultant at the InstituteDeltares in Delft, The Netherlands. In 2014 he was appointed FullProfessor at the University of Siegen. During his career, P. Reggianiworked in various applied scientific and consulting projects in Asia,Africa and Europe. An important focal point of his scientific work hasbeen the interface between numerical weather prediction and hydrologicalforecasting, including the area of forecasting uncertainty, as well asoperational water management in data-poor areas. P. Reggiani haspublished more than 60 papers in different areas of hydrology, climatechange impacts on water resources, flood forecasting, channel hydraulicsand soil science. He also acted as coordinator for several projects,among which the FP5 project “European Flood Forecasting System(EFFS)”. P. Reggiani partakes in several scientific boards on waterresources issues. He frequently acts as expert reviewer for scientificevaluations in the fields of catchment hydrology, flood forecasting,climate change impacts and natural hazard risk assessment. He is Memberof the Hydrological Services Commission at the WMO (SERCOM-HYD).
