The sea breeze at Venice,as related to daily global solar radiation     

Dario Camuffo 《Boundary-Layer Meteorology》1982,23(2):175-184

Although the sea breeze at Venice and on her hinterland is influenced by orography - mainly the Alps — to the north and the Po Valley to the west, the search for a correlation between the frequency of development of the sea breeze and the daily global solar radiation seems to be desirable, and may be useful for the management of emissions from the industrial area near Venice. Three different cases are examined: (i) the sea breeze occuring in the absence of any appreciable gradient wind; (ii) the sea breeze superimposed on a prevailing wind; (iii) the sea breeze not developing at all. The frequency distributions of these cases related to the global solar radiation at Venice are discussed.  相似文献   

Contents of Volume 53     

Dario Camuffo  Claudio Cocheo  Giovanni Sturaro 《Climatic change》2002,53(4):531-533

Volume Contents

Contents of Volume 53  相似文献   

The Role of Data Processing and Uncertainty Management in Seismic Hazard Evaluations: Insights from Estimates in the Garfagnana–Lunigiana Area (Northern Italy)     

D'amico  Vera  Albarello  Dario 《Natural Hazards》2003,29(1):77-95

Significantly different estimates of seismic hazard may result for the same site as aneffect of different methodological choices underlying the adopted procedures. In orderto explore this aspect, two approaches devoted to probabilistic seismic hazard assessment are considered for the evaluation of hazard in a seismic area in Northern Italy. In particular, results of a standard procedure are compared with those obtained by an innovative approach. Fundamental features of this last methodology are the extensive use of intensity data relative to seismic effects observed at the site of interest during past earthquakes and the basic role attributed to the parameterisation of uncertainty which affects the considered pieces ofinformation. The analysis indicates that the new approach supplies results significantlydifferent from those obtained from standard methodology and that these differences strongly depend on strategies adopted for data processing and for the management of uncertainties which affect input parameters.  相似文献   

Coupled conduit and atmospheric dispersal dynamics of the AD 79 Plinian eruption of Vesuvius     

Augusto Neri  Paolo Papale  Dario Del Seppia  Roberto Santacroce 《Journal of Volcanology and Geothermal Research》2003,120(1-2):141-160

The AD 79 eruption of Vesuvius is certainly one of the most investigated explosive eruptions in the world. This makes it particularly suitable for the application of numerical models since we can be quite confident about input data, and the model predictions can be compared with field-based reconstruction of the eruption dynamics. Magma ascent along the volcanic conduit and the dispersal of pyroclasts in the atmosphere were simulated. The conduit and atmospheric domain were coupled through the flow conditions computed at the conduit exit. We simulated two different peak phases of the eruption which correspond to the emplacement of the white and gray magma types that produced Plinian fallout deposits with interlayered pyroclastic flow units during the gray phase. The input data, independently constrained and representative of each of the two eruptive phases, consist of liquid magma composition, crystal and water content, mass flow rate, and pressure–temperature–depth of the magma at the conduit entrance. A parametric study was performed on the less constrained variables such as microlite content of magma, pressure at the conduit entrance, and particle size representative of the eruptive mixture. Numerical results are substantially consistent with the reconstructed eruptive dynamics. In particular, the white eruption phase is found to lead to a fully buoyant eruption plume in all cases investigated, whereas the gray phase shows a more transitional character, i.e. the simultaneous production of a buoyant convective plume and pyroclastic surges, with a significant influence of the microlite content of magma in determining the partition of pyroclast mass between convective plumes and pyroclastic flows.  相似文献   

History of the Long Series of Daily Air Temperature in Padova (1725–1998)     

Dario Camuffo 《Climatic change》2002,53(1-3):7-75

The history of the origin of the study of meteorology in Padova and its connection to the major developments of this science in Italy and the international context are presented. Special topics are: the scientific legacy of Galileo Galilei and the Accademia del Cimento,the birth of the first meteorological networks, i.e., Ferdinand II and Leopold de' Medici who created the Rete Medicea, J. Jurin and the network of the RoyalSociety, London, L. Cotte and the Société Royale de Médicine, Paris, J. J. Hemmerand the Societas Meteorologica Palatina, Mannheim. After outliningthe cultural background that favoured the development of meteorology, emphasis is given to the plurisecular time series of meteorological observations, taken in Padova since 1725, in its national and international context. This long series includes barometric pressure, air temperature, wind direction and speed; state of the sky and occurrence of meteorological events and precipitation. Special reference is made to indoor and outdoor temperature observations. Solar radiation falling on each exposure has been modelled in order to know when data were fully reliable and when they were less so. A vertical profile of air temperature has allowed corrections of the change of instrument level, when necessary. In terms of homogeneity, the series can be divided into several periods, during which instruments and operational methods, position, general criteria were unchanged: origins in homes of the first observers (1725–1767); the First Period at the Specola(1768–1812); the Second Period at the Specola (1813–1864); the Third and Fourth Periodsat the Specola (1865–1937); the Last Measurements at theSpecola (1938–1962); the Giovanni Magrini Observatoryof the Water Magistrate (1920–today); the Gino Allegri Airport(1926–1990), the Botanical Gardens (1980–today), the CNR (1984–1986; 1993–today). The latestperiod with the birth of new weather stations, is the most affected byanthropic effect. The simultaneous presence of an urban and a rural weather station pointed out local effects which dominate the urban heat island.  相似文献   

Errors in Early Temperature Series Arising from Changes in Style of Measuring Time, Sampling Schedule and Number of Observations     

Dario Camuffo 《Climatic change》2002,53(1-3):331-352

Study of the Padova series (1725–today) is a useful example, of general interest, of a critical revision of long time series. These are composed of a number of inhomogeneous parts, each of them with mean daily values, and extremes, computed in different ways, based on observations taken at different times, or with the time expressed in different styles. Imprecise clocks, little care for the schedule established for meteorological readings, changing style of evaluating time, inappropriate choice of observing schedules, too small a number of readings to compute the daily average, generated errors that caused significant departures in time series, that could be interpreted as a climate signal. In the past, average values were obtained with only a few daily measurements. The first problem is to correct the data and extrapolate the hourly temperatures needed to evaluate the daily minimum, maximum and average values in a homogeneous way. The change of style in temporal reference introduced spurious seasonal changes. Styles (or combinations of styles) used were: Italian time in use till 1789, in which the hours werecomputed starting from twilight; apparent solar time based on theactual motion of the sun; mean solar time based on the average motion of the sun; local time referred to the actual passage of thesun across the local meridian (local culmination); French timestarting at midnight and regulated on the local culmination; Western European Time regulated on theculmination of fictitious average solar motion on a reference meridian 15° East. A test was performed to verify whether the times chosen for readings were appropriate, in particular when observations were performed not close to the daily minimum and maximum. In effect, in the early period with Morgagni and Toaldo, the choice of schedule of observations was good, but afterwards the introduction of new observations, not always established at the most appropriate schedule, reduced the representativity of the data. The error in calculating the daily average temperature after a given number of observations taken at different hours of the day has been analysed. National, and especially international recommendations have been particularly important in the choice of observations times, and in determining averages. These recommendations have been simultaneously applied on a large number of sites, causing an in-homogeneity that may be misinterpreted as a well-documented, widespread climate change.  相似文献   

Two-mica and tourmaline leucogranites from the Everest–Makalu region (Nepal–Tibet). Himalayan leucogranite genesis by isobaric heating?     

Dario Vison    Bruno Lombardo 《Lithos》2002,62(3-4):125-150

In the Higher Himalaya of the region from Cho Oyu to the Arun valley northeast of Makalu, the Miocene leucogranites are not hosted only in the upper High Himalayan Crystallines (HHC); a network of dykes also cuts the lower HHC and the Lesser Himalayan Crystallines (LHC).

The plutons and dykes are mainly composed of two-mica (muscovite+biotite±tourmaline±cordierite±andalusite±sillimanite) leucogranite, with tourmaline≤2.6% and biotite>1.5% modal, and tourmaline (muscovite+tourmaline±biotite±sillimanite ±garnet±kyanite±andalusite±spinel±corundum) leucogranite, with tourmaline>2.2% and biotite<1.5% modal.

Both leucogranite types were produced by partial melting in the andalusite–sillimanite facies series, under LP/HT conditions constrained by the occurrence of peritectic andalusite and cordierite. The geochemical features of the leucogranites suggest that tourmaline leucogranite was produced by muscovite dehydration melting in muscovite-rich metapelites at P350 MPa and T≥640°C, whereas two-mica leucogranite was produced by biotite dehydration melting in biotite-rich metapelites at P300 MPa and T≥660–710 °C.

Melting in fertile muscovite-rich metapelites of the top of both the HHC and LHC produced magmas which were emplaced at the same structural level in which they had been generated. Melting in the biotite-rich gneiss of both the HHC and LHC produced hotter magmas which were transported upwards by dyking and eventually coalesced in the plutons of the upper HHC. A similar process also produced a network of two-mica granite at the top of the LHC in the Ama Drime–Nyönno Ri Range northeast of Makalu.

The prograde character of leucogranite melt-producing reactions in the Everest–Makalu area suggests that, here, the generation of Miocene leucogranites took place in a regime of nearly isobaric heating following nearly adiabatic decompression.  相似文献   

Instrumental seismological data since 1900 for northeastern Italy     

Claudio Margottini  Guido Martini  Dario Slejko 《地震工程与结构动力学》1993,22(12):1017-1030

Statistical analyses on a catalogue of instrumental data for earthquakes in northeastern Italy since 1900 are presented. The different types of magnitude, which are the main parameters under study, have been evaluated so as to be as homogeneous as possible. Comparisons of the different magnitude values show linear dependence, at least in the medium magnitude range represented by the available data set. Correlations between the magnitude most significant for this region and chosen macroseismic data indicate a methodology for assessing the macroseismic magnitude of historical earthquakes which seems to be stable.  相似文献   

Different approaches to the seismic hazard of Sannio-Matese (Southern Italy)     

Livio Siro  Dario Slejko 《Natural Hazards》1989,2(3-4):329-348

The seismic hazard of Sannio-Matese is calculated using a new seismogenetic zoning of southern Italy of seven areas and different, azimuth-dependent, attenuation laws. Various approaches (Gumbel's first and third asymptotic distribution, Cornell) lead to similar results for the different exposure times considered (100 and 200 years) and probability levels (37 and 68%). The present seismic regulation proposed in 1980 by the Italian National Council for Researches, and based on a different approach, is, in general, confirmed by the results.  相似文献   

Seismic behaviour of girder bridges for horizontally propagating waves     

Dario R. Somaini 《地震工程与结构动力学》1987,15(6):777-793

The results obtained from a parametric study on the influence of horizontally propagating waves for the earthquake behaviour of continuous girder bridges are presented. The investigation is performed for floating-supported bridges excited by an earthquake acting in their vertical planes. The shallow foundations are assumed to be supported on the surface of either a visco-elastic halfspace or a visco-elastic layer resting on an elastic halfspace. Steady-state response for harmonic excitation and transient response for an artificial time history are investigated. Approximate equations describing the influence of horizontally propagating waves are presented and criteria are derived indicating when an increase of the internal forces and of the relative motion between the girder and the abutments can be expected.  相似文献