Stefano Tibaldi

Stefano Tibaldi
CMCC - Euro-Mediterranean Center on Climate Change · Climate Simulation and Prediction

Laurea in Fisica
Research in Numerical Seasonal Forecasting

About

108
Publications
7,766
Reads
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3,773
Citations
Introduction
Additional affiliations
September 2015 - present
Centro Euro-Mediterraneo sui Cambiamenti Climatici
Position
  • Researcher
July 2008 - March 2015
Arpa Emilia-Romagna
Position
  • Director General
July 1996 - June 2008
Arpa Emilia-Romagna
Position
  • Head of Regional HydroMetClimate Service

Publications

Publications (108)
Article
Full-text available
Can multi-annual variations in the frequency of North Atlantic atmospheric blocking and mid-latitude circulation regimes be skilfully predicted? Recent advances in seasonal forecasting have shown that mid-latitude climate variability does exhibit significant predictability. However, atmospheric predictability has generally been found to be quite li...
Article
This paper reviews the historical development of concepts and practices in the science of ocean predictions. It begins with meteorology, which conducted the first forecasting experiment in 1950, followed by wind waves, and continuing with tidal and storm surge predictions to arrive at the first successful ocean mesoscale forecast in 1983. The work...
Chapter
A large number of hydrological forecasting systems exist across the globe. Recent advances have pushed the limits of predictability of discharge and other hydrological variables from a few hours to several days or even months. In this chapter, we aim to give an overview of Hydrological Ensemble Prediction Systems across the globe. It provides brief...
Article
Full-text available
NEGLI ULTIMI ANNI SONO MOLTO CRESCIUTE LE ASPETTATIVE (E LE LAMENTELE) RELATIVE ALLE PREVISIONE METEOROLOGICHE, CHE NON POSSONO TUTTAVIA SUPERARE UN CERTO GRADO DI INCERTEZZA INTRINSECA. BISOGNA AFFIANCARE ALLA PREVISIONE DETERMINISTICA UNA PREVISIONE PROBABILISTICA DI “ENSEMBLE”? SERVE UNA TRANSIZIONE CULTURALE.
Article
Full-text available
C on la pubblicazione della prima edizione del Rapporto integrato di sostenibilità (disponibile su www.arpa.emr.it/ris), Arpa Emilia-Romagna si è posta l' obiettivo di misurare e comunicare la responsabilità delle proprie azioni. Il documento, che presenta i dati relativi al 2013 e a cui a breve seguirà un aggiornamento al 2014, è disponibile sia i...
Article
Full-text available
La qualità e la disponibilità di prodotti e servizi meteo in Italia sono aumentati, ma non si sta chiudendo il gap con il resto dell'Europa: mancanza di un servizio nazionale civile, scarsità di fondi, disinteresse dell'accademia per la formazione dei meteorologi continuano a caratterizzare il nostro paese.
Article
Full-text available
The patterns which explain the largest fraction of the large-scale variability over the Euro-Atlantic and the Pacific regions are described using the National Centers for Environmental Prediction analysis data. In the description, special attention is given to the relation between these patterns and local weather regimes. The dynamical characterist...
Article
In this paper, an optimum interpolation scheme is applied to produce an objective daily mesoscale analysis of minimum and maximum temperatures in the Emilia Romagna region of northern Italy (essentially the Po Valley). This system is operational at the Regional Meteorological Service. The study of the autocorrelation structures of these fields show...
Article
Full-text available
The principal sources of uncertainty in hydrological forecasts are given by input errors, because of inaccurate rainfall predictions of meteorological numerical models. Many efforts have been devoting since last years to reduce this uncertainty and, now, the ensemble technique seems to be one of the most fruitful in interfacing hydrological and met...
Article
Full-text available
Summer bioclimatic discomfort is a significant public health problem. Bioclimatic characterisations of populations living in urban areas are usually very poor, although the risks are relatively higher in cities because of the phenomenon known as the "urban heat island". We compared airport, rural, and urban bioclimatic conditions in terms of appare...
Article
Full-text available
The "sea state" is the description of the properties of the sea surface waves at a given time and location. This might be given in terms of wave spectrum or more simply in terms of significant wave height, wave direction, mean and peak period; this information can be obtained by means of numerical models. The sea state operational forecast system,...
Article
Regimes of the northern extratropical circulation in winter are identified in this paper as clusters of atmospheric states in a low-dimensional phase space generated by the leading EOFs of eddy geopotential fields. In order to define the clusters, our algorithm seeks points corresponding to local maxima for the density of atmospheric states; subseq...
Article
A classification of hemispheric flow patterns into clusters corresponding to circulation regimes is used to analyse the errors in geopotential fields predicted by the ECMWF models in the medium range during winter. It is found that the probability distributions of both the r.m.s. error over the northern hemisphere and the amplitude of large-scale p...
Chapter
Introduction The improvement of quantitative precipitation forecasting (QPF) is still one of the major challenges in numerical weather prediction (NWP). Despite the constant increase of computer power resources, which has allowed the development of more and more sophisticated and resolved NWP models, accurate forecasts of extreme weather conditions...
Article
Full-text available
The predictability of the flood event affecting Soverato (Southern Italy) in September 2000 is investigated by considering three different configurations of ECMWF ensemble: the operational Ensemble Prediction System (EPS), the targeted EPS and a high-resolution version of EPS. For each configuration, three successive runs of ECMWF ensemble with the...
Article
The use of Ensemble Prediction Systems with General circulation models is well established regarding the medium-range and beyond. The possibility of applying an ensemble approach with limited area models, even at shorter time ranges, has recently been considered as a new and potentially important branch to be investigated to better quantify the unc...
Article
The limited-area ensemble prediction system COSMO-LEPS has been running operationally at ECMWF since November 2002. Five runs of the non-hydrostatic limited-area model Lokal Model (LM) are available every day, nested on five selected members of three consecutive 12-hour lagged ECMWF global ensembles. The limited-area ensemble forecasts range from 2...
Article
The CLOUDS study defines a small satellite addressing the objective of cloud-radiation interaction monitoring for improved climate and weather prediction. The study was funded by the EC, and now various paths are explored to provide study continuation and eventual programme implementation. The payload only includes passive radiometers, covering the...
Article
Possible connections between spatial patterns, of limited regional extent and identified in teleconnection patterns and in blocking climatology studies, with hemispheric planetary-wave activity modes defined by the wave amplitude index (WAI) are investigated. The WAI probability density function (PDF) for the northern extratropics winter fields is...
Article
Full-text available
Many researches have highlighted the influence of climate on mortality, showing a high increase in mortality in summer time during “heatwaves”, periods with very high temperature and humidity levels. This relation seems to be stronger than those between mortality and other environmental factors, such as atmospheric pollution.1 According to estimate...
Article
Full-text available
The winter precipitation variability over the Alpine region is described by a standard principal component analysis (PCA), performed starting from monthly precipitation anomalies for the 1971-1992 winters. With respect to the temporal variability, significant trends are found over some areas within the domain. In particular, the Alpine orography si...
Article
A high-resolution ensemble system, based on five runs of a limited-area model (LAM), is described. The initial and boundary conditions for the LAM integrations are provided by the representative members (RMs) selected from the European Centre for Medium-Range Weather Forecasts Ensemble Prediction System (EPS). EPS members are grouped in five cluste...
Article
In the framework of the Integrated Decision Support System for air quality assessment and management operating at the Emilia-Romagna Region Meteorological Service, an appropriate meteorological input is necessary: 1) to provide meteorological information for evaluation of the pollution data observed at the urban monitoring stations; 2) as input dat...
Conference Paper
CLOUDS is a project supported by the European Union, conducted by 12 European partners (7 scientific institutes and 5 industrial companies), also cooperating with NOAA/ETL. It is the mission study of a monitoring satellite to perform measurements necessary to describe cloud-radiation interaction in operational models for climate and weather predict...
Article
Full-text available
Possible connections between spatial patterns, of limited regional extent and identified in teleconnectionpatterns and in blocking climatology studies, with hemispheric planetary-wave activitymodes defined by the wave amplitude index (WAI) are investigated. The WAI probabilitydensity function (PDF) for the northern extratropics winter fields is est...
Article
Pollutant concentrations relative to the years 1993-1995 measured in the Bologna urban area by a network of automatic stations (S.A.R.A. Sistema Automatico di Rilevamento Ambientale) are analysed to estimate the typical behaviour of the pollutants, especially with regard to periodicities and meteorological dependencies and to attempt prediction for...
Article
Pollutant concentrations relative to the years 1993-1995 measured in the Bologna urban area by a network of automatic stations (S.A.R.A. Sistema Automatico di Rilevamento Ambientale) are analysed to estimate the typical behaviour of the pollutants, especially with regard to periodicities and meteorological dependencies and to attempt prediction for...
Article
Full-text available
 As a part of the Atmospheric Model Intercomparison Project (AMIP), the behaviour of 15 general circulation models has been analysed in order to diagnose and compare the ability of the different models in simulating Northern Hemisphere midlatitude atmospheric blocking. In accordance with the established AMIP procedure, the 10-year model integration...
Article
Full-text available
 An analysis of blocking events is conducted on the output of four integrations of the ECHAM3 atmospheric general circulation model with different configurations of horizontal spectral truncation and oceanic surface temperatures. The definition of local blocking and sector blocking is obtained by using an objective index based on a measure of the l...
Article
Full-text available
 To assess the extent to which atmospheric low-frequency variability can be ascribed to internal dynamical causes, two extended runs (1200 winter seasons) of a three level quasi-geostrophic model have been carried out. In the first experiment the model was forced by an average forcing field computed from nine winter seasons; in the second experimen...
Article
Full-text available
We outline here the logical flow of papers that attack the problem of estimating the wave conditions in front of and at the Venetian littoral. We start from the determination of the wind fields, followed by that of the wave fields. The wave data are then transferred to the coast. We end by analysing the wave conditions inside the main inlet to the...
Article
Full-text available
We propose to use an Artificial Neural Network (ANN) for meteorological blocking recognition. The network output is presented as a number which ranges between 0 (absence of blocking) and 1 (blocked situation). This output is then compared with the step function obtained with a blocking index used in meteorological analysis and in the recognition of...
Article
Full-text available
A severe storm in the Adriatic Sea has been hindcast with two meteorological models, respectively at the local (LAMBO) and global scale (T213). We have found that the increase of resolution is not paralleled by a corresponding increase of the overall accuracy. This is particularly true when the wind fields are used to evaluate the corresponding wav...
Article
After a description of the monthly distribution of thunderstorm occurrence in the Po Valley and in the Northern Adriatic region and an identification of the homogeneous areas in terms of the contemporary occurrence of the phenomenon, this study examines the dynamic and thermodynamic characteristics of the atmosphere that are conducive to the develo...
Article
Full-text available
The main observational difference between blocking in the two hemispheres is in the number of preferred locations: Atlantic and Pacific blocking in the Northern Hemisphere, and only one broad region in the Southern Hemisphere, around 180° longitude. Forecasting the onset of blocking events is in general a task that the model finds difficult, wherea...
Article
An attempt is made to characterize the mesoscale climatological structures of the daily maximum and minimum temperature anomalies (with respect to monthly climatology) and total daily precipitation of the Emilia Romagna region of northern Italy (essentially the Po Valley) by means of multivariate statistical analysis techniques. Firstly, a definiti...
Article
In this study, a possible relationship between global wintertime weather regimes in the northern hemisphere (NH) mid latitudes and the total precipitation over mainland China in the season following is investigated. Weather regimes are defined, as by Molteni et al. (1990), as clusters in the low-dimensional phase space of the leading rotated EOFs o...
Chapter
Atmospheric General Circulation Models (AGCMs) are being employed more and more extensively for climate impact studies, often coupled with Ocean General Circulation Models (OGCMs) to give what is commonly referred to as a Global Climate Model.
Article
Nel presente lavoro viene analizzata la capacità di un modello di circolazione generale (ECMWF), usato operativamente per previsioni del tempo, di prevedere i campi di precipitazione su scala regionale per periodi dell'ordine del mese, alla luce dei miglioramenti più recenti, sia in termini di risoluzione spaziale, sia in termini di parametrizzazio...
Article
A number of forecast experiments were performed in order to assess the capability of reproducing, by means of a limited-area numerical model, the highly structured mesoscale circulations occurring in the Po Valley of Northern Italy during a north-westerly cold front passage across the Alpine chain, with particular attention to the modelling of the...
Article
In this paper the problem of computing large-scale trajectories of atmospheric parcels is examined in the framework of a numerical limited-area model used for weather prediction. The parcel of air is considered to be a completely passive tracer, having no interaction with the environment, even when going through an area of deep atmospheric convecti...
Article
Full-text available
Results from a 3 1/2-yr experimental program of extended-range integrations of the European Centre for Medium-Range Weather Forecasts (ECMWF) numerical weather prediction model are summarized. The topics discussed include1) The evolution of extended-range systematic error and skill in forecasting large-scale weather regime transitions;2) The depend...
Article
The influence of horizontal resolution on model systematic error and skill scores are examined for both winter and summer seasons from a set of extended-range integrations of the European Centre for Medium Range Weather Forecasts (ECMWF) numerical weather prediction model. the forecast data are composed of 24 30-day integrations, two per month from...
Article
In practice, about a third of the ensemble-mean forecasts, at forecast days 11-20, were more skilful than both persistence and climate, and, in addition, were more skilful than the latest member of the ensemble. At days 21-30, only one of the ensemble-mean forecasts was similarly skilful. Whilst there is an overall hemispheric scale correlation bet...
Article
Diagnostics of zonal average 30-day mean wind and temperature error show a systematic reduction in the extratropics over three years. It is argued that these improvements are consistent with the changes in model formulation. Eddy fluxes of heat and momentum, and levels of eddy kinetic energy are similarly improved. We also show that the ability to...
Article
The entire 7-year archive of ECMWF operational analysis and forecast data is used to assess the skill of the Centre's model in short- and medium-range forecasting of atmospheric blocking. The assessment covers 7100-day periods, from 1 December to 10 March of all winters from 1980-81 to 1986-87, inclusive. A slightly modified version of the Legenäs...
Article
Regimes of the northern extratropical circulation in winter are identified in this paper as clusters of atmospheric states in a low-dimensional phase space generated by the leading EOFs of eddy geopotential fields. Our algorithm seeks points corresponding to local maxima for the density of atmospheric states; subsequently, a cluster is defined arou...
Article
In this paper, an optimum interpolation scheme is applied to produce an objective daily mesoscale analysis of minimum and maximum temperatures in the Emilia Romagna region of northern Italy (essentially the Po Valley). This system is operational at the Regional Meteorological Service. The study of the autocorrelation structures of these fields show...
Article
Full-text available
Using 10-day forecast 500 mb height data from the last 7 yr, the potential to predict the skill of numerical weather forecasts is discussed. Four possible predictor sets are described. The first, giving the consistency between adjacent forecasts, is apparently more skillful if the anomaly correlation coefficient, rather than RMS difference, is used...
Article
Based on the continuity of the atmosphere, a new scheme is developed to diagnose the atmospheric mean meridional circulations. ECMWF analyses four times per day of January 1982 were retrieved to evaluate the global mean meridional circulation. Investigations and calculations show that this new scheme produced more reasonable results in comparison w...
Article
Experiments using a quasi-geostrophic model and theECMWF T21 spectral model with and without orography are performed to investigate the effects of mechanical forcing on the mean meridional circulation. Results show that mechanical forcing intensifies the horizontal poleward heat flux and redistributes the eddy angular momentum in the vertical, and...
Article
Cyclogenesis is known to take place frequently near the principal mountain complexes of the earth. However, a coherent and comprehensive theory of orographic cyclogenesis has never been offered in the literature. We propose here a unified theory of cyclogenesis in the presence of orography of various configurations, based on the generalization of a...
Article
This chapter describes the envelope orography and maintenance of the quasistationary circulation in the European Centre for Medium-range Weather Forecasts (ECMWF) global models. The global data for the month of January 1981, notable for the anomalously large amplitude of the monthly-mean error of the operational ECMWF forecast model, have been repr...
Article
The role of surface thermal forcing in increasing the predictability of low-frequency large-scale atmospheric anomalies was assessed using model runs of winter 1982 to 1983, with the strong El-Nino event. The experiment is composed of two lagged-average forecasting sets of integrations, each consisting of 9 forecasts initiated from adjacent analysi...
Chapter
The importance of the corrugations of the lower boundary of the Earth’s atmosphere in causing both weather and climate to depart from axial symmetry has long been recognized (e.g. Charney and Eliassen, 1949; Bolin, 1950). General Circulation Models (GCMs), if they are to represent realistic mean atmospheric states and departures from them, must hav...
Article
Two Observing System Experiments were carried out at (ECMWF). The European Center for Medium Range Weather Forecasting impact of various observing systems were examined for two periods during the EGGE year: November 8 to 9, 1979 (OSE-1) and February 22 to March 7, 1979 (OSE-II). Attempts were made to understand the effect of the observing systems o...
Article
Full-text available
The onset of the 1979 summer monsoon is investigated using the ECMWF grid-point model. The role of the Tibetan Plateau in this process is investigated by means of parallel model integrations with different orographies. Similarly, the relative roles of land-sea thermal contrast, latent heat release and Southern Hemisphere influence are studied. The...
Article
In part II of this paper, the effects of diabatic heating and the Tibetan Plateau on the seasonal transition of the general circulation over Asia is investigated. It is shown that the effect of diffefential heating mainly due to land-sea contrast dominates even for a medium time scale. The effect of the Piateau seems to reinforce but not radically...