1,721,074 research outputs found
Land–Sea Distribution of Ground Precipitation in Mediterranean Storms
Full text linkThe Mediterranean basin is traditionally a hotspot where copious amounts of water vapor at low- and mid-tropospheric levels often favor atmospheric instability and the deepening of storms, leading to intense rainfall events with consequent flash floods. Moreover, this region includes sharp land-sea transitions, narrow maritime areas, and mountain chains which enhance convective precipitation. In this study, radar precipitation data were used to investigate the spatial distribution of rainfall swaths for seven severe cyclones originating over the Mediterranean Sea which produced intense flash inundation events along the western coast of Italy in the last decade (2011-2020). Based on 5 min precipitation amounts gridded at a 1 km spatial resolution, the temporal evolution of these storms displays a curvilinear path moving from sea to inland. Results show that more than half of the total precipitation for the analyzed events occurred on sea, and the total amount of storm rainfall over the marine surface exceeded that over land in four events out of the seven. Since the coastline strongly affects the rainfall pattern, we analyzed the land-sea discontinuity, which is a key factor controlling the spatial distribution of storm rates through their trajectory, where a small shift in precipitation target might smooth ground effects and mitigate flood impacts
Testing FEST-WB, a continuous distributed model for operational quantitative discharge forecast in the upper Po river
No full textAn Operational Hydro-Meteorological Chain to Evaluate the Uncertainty in Runoff Forecasting over the Verbano Basin
No full textThe development and implementation of a real-time flood forecasting system with a hydro-meteorological operational
alert procedure during the MAP-D-PHASE Project is described in this paper. This chain includes both probabilistic and deterministic
forecasts. The hydrological model used to generate the runoff simulations is the rainfall-runoff distributed FEST-WB model,
developed at Politecnico di Milano. The observed data to run the control simulations were supplied by ARPA-Piemonte. The analysis
is focused on Maggiore Lake basin, an Alpine basin between North-West of Italy and Southern Switzerland. Two hindcasts during
the D-PHASE period are discussed in order to evaluate certain effects regarding discharge forecasts due to hydro-meteorological
sources of uncertainties. In particular, in the June convective event it is analysed how the effect of meteorological model spatial
resolution can influence the discharge forecasts over mountain basins, while in the November stratiform event how the effect of the
initial conditions of soil moisture can modify meteorological warnings. The study shows how the introduction of alert codes appears to
be useful for decision makers to give them a spread of forecasted QDFs with the probability of event occurrence, but also how alert
warnings issued on the basis of forecasted precipitation only are not always reliable
Hydro-meteorological chain for flood forecasting in the Toce basin: a multi-model comparison
No full textMapping drought characteristics in northern Algerian Basins using the ERA5-Land dataset
Full text linkOver the past decades, drought events have led to significant agricultural losses and water shortages in the Algerian catchments; these hydro-meteorological phenomena strongly affect the entire Mediterranean region, and its frequency and intensity may increase due to climate change. The purpose of this study is to investigate drought conditions in the northern region of Algeria using the standardized precipitation index (SPI) at different monthly scales (3, 6, 12, 24 months), calculated through the ERA5-Land monthly dataset, which provides a much more detailed mapping of drought vulnerability across the country compared to observed rain gauge data, whose ground distribution is sparse and whose data archive is neither homogeneous nor complete for the study area. The main characteristics of drought events (e.g., quantity, duration, severity, and intensity), that have historically affected several hydrological basins in the northern part of the nation, are examined using the run theory applied to SPI values from 1950 to 2022. Although a high number of occurrences appear at shorter timescales, the results indicate that these episodes generally have shorter durations and lower severity compared to long-timescale droughts. Specifically, a decrease in the average number of drought events as the timescale increases is found: from 69 events for the 3-month SPI, with an average duration of about 2 months, to 17 events for the 24-month SPI, with an average duration of approximately 8 months. By analysing the spatial and temporal distribution of drought features, this approach aims to identify areas experiencing water stress and support more effective water management and mitigation strategies
Application potentiality of a costeffective X-band weather radar for the quantification of precipitation in northern Italy
No full textEvaluating the uncertainty of hydrological model simulations coupled with metorological forecasts at different spatial scales
No full textIn recent years, the interest in the prediction and prevention of natural hazards related to hydro-meteorological events has increased the challenge for numerical weather modeling, in particular for limited area models, to improve the Quantitative Precipitation Forecasts for hydrological purposes. In this study a hindcast for some precipitation events, occurred in Piemonte region and in the Maggiore Lake basin, is analyzed to evaluate how the uncertainty of meteorological forecasts influences the performance of hydrological predictions at different spatial scales. This hydro-meteorological chain includes both probabilistic forecasting based on ensemble prediction systems and deterministic forecasts based on high resolution atmospheric models. The hydrological model used to generate the runoff simulations is the rainfall-runoff distributed FEST-WB model, developed at Politecnico di Milano
Uso di misure eddy correlation e di un modello di bilancio di massa ed energia per meglio interpretare i flussi misurati
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