Showing papers on "Urban climate published in 1981"

A model analysing the urban thermal environment in physiologically significant terms

Abstract: Traditional heat island studies usually do not include bioclimatic aspects and are therefore of limited use to planners. We suggest a quantitative model for the assessment of the thermal urban climate component in physiologically significant terms. It is based on an adaption of Fanger's comfort (PMV) equation to outdoor conditions. This is achieved by parameterizing short and long wave radiative fluxes using easily obtainable meteorological data. Special emphasis is given to the change in radiation conditions within different urban structures. The spatial distribution of PMV values for a daytime and a nighttime situation in Freiburg i.Br., FRG, is presented.

Urban Development In Modern China

Abstract: This is a collection of studies that illustrate the geographical political and economic aspects of the Chinese city beginning with urbanization in the late nineteenth and early twentieth centuries and emphasizing contemporary urban patterns. Topics covered include recent growth and change in Chinas urban system policies favoring the growth of smaller urban places between 1949 and 1979 trends in urban planning and development and causes of urban sprawl. (ANNOTATION)

Conversion of rural land to urban: a canadian profile

Abstract: How do land conversion rates throughout the urban hierarchy respond to changes in economic, demographic, and physical factors? An analysis of the quantity and intensity of rural land consumed for urban development highlights certain regularities in the urban growth process as well as great variability. Population change, economic function, and soil capability show the greatest promise in explaning the provision of land for urban development. It is concluded that more systematic and sensitive measures of urban land-use requirements are needed before urban and rural land uses can be budgeted effectively.

Extra urban and intra urban rainfall enhancement by a medium sized city

Abstract: An experiment on urban effects of warm season rainfall of a moderately sized city and its downwind towns found no evidence of global enhancement. However, there are grounds for believing that the intra urban distribution of precipitation is influenced by urban variables among which air pollution and urban roughness are considered primary. The presence of an urban heat island did not appear to improve rainfall. On the contrary, it appears to be a factor in the relative aridity of the downtown sector of the city.

Fluctuations in the land-use composition of urban development during the industrial era

Abstract: Wahl der Wochenmitten oder Wochenenden, der Weinfe ste, der Bevorzugung bestimmter Jahreszeiten usw., auf die im Text naher eingegangen wurde. Die fiir Pkw-Zahlungen und Befragungen ausgewahlten Tage werden in der Literatur oft als ?reprasentativ\" bezeichnet. Aus den hier vorgelegten Untersuchungsergebnissen geht m. E. eindeutig hervor, dafi es solche fur die ganze Saison ?reprasentativen Tage\" nicht

Population and the urban future.

Abstract: Urbanization is a recent phenomenon. Around the year 1800 less than 3% of the worlds population lived in urban areas; by 1920 the figure had risen to 14% and by 1950 to 25%. It is estimated that by the year 2000 51% of the worlds population will be concentrated in urban areas. The urban population of the world has been growing at nearly 3% per annum 1.7% in developed countries and over 4% in developing countries. By the year 2000 12 giant cities with a population in excess of 10 million will be in less developed countries. The nature and composition of rural-urban migration in developing countries have caused the proliferation of urban slums pollution and degeneration of the environment congested living conditions and excessively high urban energy costs. Urban employment already a big problem will intensify. Population policies must be integrated into urban planning and programming; decentralized investment of capital and the geographical redistribution of employment opportunities must be encouraged; at the same time social services and living opportunities in rural areas must be improved and the growth of smaller cities promoted. 4 elements should be included into a strategy for national planning for the urban future: 1) policies for redistribution of population 2) policies for revitalization of urban centers 3) policies for decentralization of development and 4) measures to stabilize the population within cities.

Air Pollution Effects on Climate at Urban Scale

Abstract: After a general introduction, air pollution influence on urban climate is described. Following this, there is a description of urban boundary layer, urban canopy layer and the urban heat island. This last is held responsible for various climatic characteristics of the urban area. Then, there is a discussion about two main meteorological elements characterizing the urban climate: precipitation and wind velocity. Finally, urban area visibility is briefly presented.

The Urban Environment

Abstract: The environment-behavior literature related to the urban environment is in many ways as complex and diverse as the city itself. While traditionally the province of urban sociology, the urban crises of the past two decades have prompted considerable research into the nature and consequences of city life from a social psychological perspective as well. Some of the most recent work in this area has endeavored to apply and integrate environment- behavior theory and research on such concepts as density, crowding and sensory overload with more traditional views of urban life.