Search results for "URBAN SYSTEM"
showing 10 items of 10 documents
Assessing Urban System Vulnerabilities to Flooding to Improve Resilience and Adaptation in Spatial Planning
2018
Fluvial, pluvial and coastal flooding are the most frequent and costly natural hazard. Cities are social hubs and life in cities is reliant on a number of services and functions such as housing, healthcare, education and other key daily facilities. Urban flooding can cause significant disruption to these services and wider impacts on the population. These impacts may be short or long with a variably spatial scale: urban systems are spatially distributed and the nature of this can have significant effects on flood impacts. From an urban-planning perspective, measuring this disruption and its consequences is fundamental in order to develop more resilient cities. Whereas the assessment of phys…
Aviation Contrail Cirrus and Radiative Forcing Over Europe During 6 Months of COVID‐19
2021
Abstract The COVID‐19 pandemic led to a 72% reduction of air traffic over Europe in March–August 2020 compared to 2019. Modeled contrail cover declined similarly, and computed mean instantaneous radiative contrail forcing dropped regionally by up to 0.7 W m−2. Here, model predictions of cirrus optical thickness and the top‐of‐atmosphere outgoing longwave and reflected shortwave irradiances are tested by comparison to Meteosat‐SEVIRI‐derived data. The agreement between observations and modeled data is slightly better when modeled contrail cirrus contributions are included. The spatial distributions and diurnal cycles of the differences in these data between 2019 and 2020 are partially caused…
Optical Remote Sensing in Urban Environments
2016
International audience; Cities today face a variety of issues: attractiveness and economic development, living conditions and urban redevelopment, the quality of life of citizens and the environmental conditions of the urban system as a whole. These challenges reflect the situations in urban territories where the economic development and population growth required for stabilizing the urban system come into conflict with the promotion of esthetic urban improvements appropriate for social cohesion and ensuring the safety of users while guaranteeing a reduction of the environmental impact caused by urban spread [WGI 14, WEB 15, MAC 07, WIL 11]. The process of urbanization, which has significan…
Territorial tripolarization in Bolivia : genesis and current situation
2012
The Bolivian urban system is outstanding : three major cities concentrate about half of the nation’s population and employment. Their territories’ trajectories lead us to question their economic role in the face of the successful economic achievement of Potosi and Tarija, territories well endowed in natural resources. We wanted to highlight the Bolivian current territorial tripolarization, firstly by studying its emergence, through the study of their economical history; secondly, by investigating the most recent economical data in order to display the strengths and weaknesses of this tripolarized system. Each component of the tripole is situated in a different geographical setting. In the W…
Comprehending city and its production in Africa through a systemic approach : example of the city of Diamniadio, Dakar
2022
For a long time, the analysis of the production of the city in Africa was based on an exogenous perception according to urban models theorized and experimented with in the Occidental countries, then diffused and applied through different mechanisms in the South, bearing witness to historical relations - through the making of the colonial city - and present relations - in the context of the making of new towns. After independence, researchers looked at the redefinition of the city in Africa with its complexity and plurality according to geographical and historical trajectories, proposing new urban theories that were more nuanced and linked to local and contextual realities. Therefore, follow…
Modelling urban networks sustainable progress
2019
In this paper, we analyse the relations between thermodynamics and city networks: an increase in the complexity and the organized information in such urban systems leads to less demand for resources and less social entropy, which overall makes them more efficient and stable. The goal of this study is to propose a method to measuring city networks sustainable progress based on statistical models, derived from Eurostat databases and NASA satellite images, and capable of analyzing different conceptual scenarios of urban development in Europe. The obtained probability-based indices enable us to evaluate the dynamics of city networks in terms of three components of sustainable progress – economi…
Historia urbana y mezzogiorno de Italia en la Edad Moderna: propuesta de un cuestionario
1998
The history of urbanization has barely been analyzed for the Mezzogiorno in Italy. This has partly been due to the persistence of stereotypes in Italian historiography, and partly due to the current definition of city functions. The article results from a meeting of specialists in Early Modern southern Italian history organized to undertake the rigorous and detailed study of the common features and the differences within the urban systems of the Mezzogiorno, in order to synthesize the specific character of urbanization in southern Italy over the long term. The author outlines the main areas under study and establishes its methodological foundations and first hypotheses.
Transformaciones sociales y territoriales en el incremento de la movilidad por razón de trabajo en Andalucía
2007
Entre 1991 y 2001, tal como se deduce de la información de los censos de población de ambos años, se ha producido un importante incremento de la movilidad en Andalucía por razón de trabajo, especialmente de los desplazamientos entre municipios cercanos. Este trabajo indaga sobre los factores relacionados como causas, y también como consecuencias, con tal incremento. En primer lugar, los cambios en la estructura sectorial, ocupacional y socioeconómica de la población ocupada. En segundo lugar, la ampliación espacial de los mercados locales de trabajo. Y, en tercer lugar, la evolución de la organización espacial de la movilidad, especialmente de la movilidad metropolitana. La conclusión es qu…
Measuring the hierarchical organisation of an urban system
1993
International audience
L’aire urbaine de Valencia dans le système global des villes : Les effets de la crise économique sur le réseau des liens financiers des entreprises m…
2021
El artículo analiza el impacto que la crisis económica ha tenido sobre las redes de relaciones de propiedad-filiación de las empresas multinacionales, consideradas en la literatura científica como uno de los factores más importantes en la integración de las ciudades en la globalización. El caso de estudio es el área metropolitana de Valencia, un centro de segundo nivel en las redes económicas mundiales que ha sido duramente golpeado por los efectos de la crisis desde 2008. A partir del análisis de bases de datos de empresas multinacionales en dos fechas de referencia, 2010 y 2013, se constata que la crisis económica ha provocado un retroceso en la inserción del área metropolitana en dichas …