5,476 research outputs found
Italian Academy Colombia Fellowship
No full textDuring the fall semester spent at the Italian Academy , cosponsored by the Earth and Environmental Engineering Department of Columbia University of New York, I worked on the research project ‘ Climate changes from decade to century: flood/drought dynamics’.
Such a research project involves different partners and Institutions , namely Columbia University (USA) , University of Rome ‘ La Sapienza’(Italy) , National Research Center (CNR-Italy), Institute of Numerical Model (Russian Science Academy), University of Tuscia Italy).
The research goal is to produce scientifically sound scenarios of flood and drought risk in N. America and Europe and their projected changes under IPCC scenarios.
A novel integrated modelling approach is used to address this issue. The approach entails integration of analyses from a low order dynamical systems model, a medium resolution current ocean-atmosphere GCM, and statistical tools for connecting atmospheric moisture transport and extreme precipitation incidence to the underlying low frequency climate state.
A low order model explores the interactions of the key natural modes of ocean-atmosphere variability and their interaction with the mid-latitude atmosphere.
The CGM model INMCM3.0 (Volodin & Diansky 2006) allows to simulate planetary climatic conditions for long periods of time under current conditions and under enhanced greenhouse gases conditions. However, given its complexity only a limited number of ensemble runs can typically be performed for a fixed set of parameters. Thus, its use is complementary to the low order models where substantial exploration of the parameters and the associated regimes can be done.
In the Fall semester spent in the Italian Academy the research has been addressed to study:
- the organization and evolution of climate extremes in the mid-latitude as they are influenced by low-frequency climate modes associated with ocean-atmosphere interactions; specifically such influences have been explored by using observations and low-order models.
- precipitation extremes simulated by the medium resolution GCM ( INMCM3.0) as are analyzed for the Mediterranean region.
The main findings of the study are extensively discussed in the paper ‘Surface Temperature Gradient and their relation to Mid-latitude Circulation Dynamics & Interannual Precipitation variability: Trends and links to Enso in Observations and Low-order Climate Models ’ by C. Karamperidou, F. Cioffi & U. Lall, and in the two presentations at the AGU2010 Fall Conference , namely (a) ‘"Northern Hemisphere Meridional and Zonal Temperature Gradients and their Relation to Hydrologic Extremes at Mid-latitudes: Trends, Variability and Link to Climate Modes in Observations and Simulations" , by C. Karamperidou, U. Lall & F. Cioffi ; (b) GCM Projections of Precipitation Extremes in the Mediterranean: Changes and Low frequency Characteristics by F. Cioffi ; U. Lall , E. Volodin , C. Karamperidou , R. Purini .
These findings are summarized in the following. The analysis of rainfall patterns under global warming shows an increase of rainfall extremes in both frequency and intensity in northern Europe and a decrease in most of the Mediterranean. In the latter region an increase of dry conditions is also observed. The change in the rainfall patterns can be explained by a northward shift of the North Atlantic winter storm track that is one of the main factors in determining moisture and heat transport associated with extreme hydrological events. It depends on how the jet stream dynamics are modulated by large scale ocean-land boundary conditions which depend in turn on both the state of evolution of the known inter-annual and multi-decadal natural variability ( e.g. El Nino-Southern Oscillation (ENSO) and the North Atlantic Oscillation (NAO)) and on changes in meridional and zonal surface temperature gradients ( Equator- Pole gradient (EPG) and Ocean-Land contrast ( OLC), respectively). From the 20th century observations is emerged that different combinations of EPG and OLC are associated with precipitation anomalies at mid-latitudes as Mediterranean and European regions. The Northward shift of the North Atlantic storm track and the associated rainfall patterns are related to a reduction of both EPG and OLC as a consequence of anthropogenic forcing
Ricerche di Architettura dalla città al territorio
No full textGli studi presentati in questa silloge, supportate da ricerche archivistiche e supportati da incisive riflessioni critiche, raccolgono gli esiti di ricerche incentrate sull'analisi di contesti urbani e territoriali finora poco esplorati. Cioffi indaga gli esiti delle politiche per l’abitazione del governo fascista attraverso l’esame delle case rurali costruite dall’Opera Nazionale Combattenti, che rappresentano un momento qualificato della ricerca architettonica italiana degli anni Trenta del Novecento. Cirillo propone una circostanziata ricerca su alcuni spazi commerciali progettai dall’architetto Davide Pacanowfsky che seppe conferire alle proprie opere caratteri originali ispirati alla lezione della modernità milanese e al fascino irresistibile di Le Corbusier, conosciuto personalmente tra il 1930 e il 1935. Jacazzi amplia i confini della grande stagione del Settecento napoletano attraverso lo studio degli edifici costruiti a L’Avana dall’ingegnere Francesco Vanvitelli. Infine, Serraglio descrive il progetto del centro di fondazione di Pedrinhas Paulista, costruito tra il 1951 e il 1953 nella provincia di San Paolo per una colonia di agricoltori italiani emigrati in Brasile nel secondo dopoguerra
Rifare dalle rovine. Città di scheletri a Pescopagano.
No full textRifare dalle rovine. Città di scheletri a Pescopagano. Responsabile Scientifico: Cherubino Gambardella, Gruppo di ricerca: Efisio Pitzalis, Marino Borrelli, Luca Molinari, Lorenzo Capobianco, Gianluca Cioffi, Francesco Costanzo, Corrado Di Domenico, Maria Gelvi, Fabrizia Ippolito, Raffaele Marone, Concetta Tavoletta. Dottoranti: Francesca Filosa, Marco Pignetti, Luigi Arcopinto
Studenti: Antonella Lanzano, Federica Leone
Progetto esposto nella sezione Università per La Biennale di Venezia 202
Analisi dei profili di velocità e concentrazione di solidi in un canale rettangolare a fondo mobile
No full textFrom rooted to floating vegetal species in lagoons as a consequence of the increases of external nutrient load: An analysis by model of the species selection mechanism
No full textIn this paper, the substitution mechanism of rooted aquatic plants (as eelgrass) with floating species (as Ulva r.) in lagoons are inquired by using a eutrophication model. The simulations carried out for the specific case of the Lagoon of Tortolì, in Sardinia (Italy), demonstrate the determinant role played by the increase of external phosphorous loads in the vegetal species selection and offer a possible explanation of the selection mechanism. Once the maximum accumulation capability of adsorbed phosphorous in sediments is reached, the rate of external phosphorous loads produces an increment in the dissolved phosphorous in the water column; such an increment favours the growth of floating species which inhibit, mainly due to light competition effect, the growth of rooted plants. In the paper, the serious consequences of such a selection in terms of eutrophication processes and vulnerability of anoxic crises are emphasised. © 2005 Elsevier Inc. All rights reserved
A two-dimensional self-adaptive hydrodynamic scheme for the assessment of the effects of structures on flooding phenomena in river basins
No full textIn order to assess the effects of river and floodplain engineering projects on flooding, a new self-adaptive hydrodynamic scheme for the simulation of two-dimensional river flows is proposed. The depth-averaged motion equations are solved numerically using a fractional step method, in which the convective terms are calculated using the inverse characteristics method and the remaining terms with an explicit method based on a finite difference method. The integration is performed on a dynamically self-adaptive calculus grid, which allows representation of the movable boundary between wetting and drying regions of the basins to follow the effective developments in time and space, of the expansion phenomenon of flood. The proposed procedure allows the grid's dynamic refinement to avoid coordinate transformation or the use of unstructured grids. The proposed method is simple and allows the thickening of the grid to accommodate the flooding phenomena on the floodplain and to calculate the velocity in the domain regions in which a higher space resolution is required. Therefore, flows running through structures such as weirs, gates, bridges or culverts can be simulated. In the paper two different-case studies, approached with the proposed self-adaptive calculation scheme, are discussed. The studies concern the analysis of the effects of structures, such as roads or embankments, on flooding phenomena in the Tiber and Tanaro basins respectively. Copyright (C) 2003 John Wiley Sons, Ltd
Management strategies for the control of eutrophication processes in Fogliano Lagoon (Italy): a long term analysis using a mathematical model
No full text
Dynamic behaviour of lagoon ecosystems
No full textAn analysis of coastal lagoon ecosystem dynamics is proposed the aim is to achieve a better understanding of mechanisms responsible of vegetal species substitution and water anoxia phenomena occurring in lagoons as a consequence of eutrophication such a understanding is fundamental to individuate more effective management strategies for the control of eutrophication processes.
The analysis is carried out by using a eutrophication model which allows the simulation of the temporal evolution of the concentration in the water column and into sediments of the significant species affecting eutrophication phenomena.
The dynamic behaviour of the lagoon ecosystem state, for an assigned parameter space, is analysed by simulations carried out varying both the phosphorous external load and the maximum tidal flow rate at the inlet connecting the lagoon to the sea , which were assumed as control parameters.
The response diagram, obtained by simulations, varying the value of control parameters, shows the existence of different ranges of stability of the ecosystem, characterized by the dominance of a specific group of primary producers and by a different ecosystem vulnerability to summer water anoxia. A catastrophic bifurcation, which manifests as an abrupt change of the dominant species from eelgrass to macro algae, occurs for some critical values of the control parameters
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