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Showing papers on "Urban climate published in 2000"


Journal ArticleDOI
TL;DR: In this article, the cooling effect of small urban green wooded sites of various geometric configurations in summer is studied experimentally at 11 different green sites in the Tel-Aviv urban complex during the period July-August 1996.

620 citations


Journal ArticleDOI
TL;DR: In this paper, the authors investigated if, how and when knowledge about the climate is used in the urban planning process and found that climate issues often have a low impact on the planning process in practice, despite the fact that the urban landscape creates a climate which influences human comfort, air quality and energy consumption.

412 citations


Journal ArticleDOI
Marc Antrop1
TL;DR: In this paper, the authors discuss the complex interaction of different processes which transform landscapes formed by rural life styles into urban like ones, and the existing cities and urban network form the framework for this change, which is affecting increasingly larger areas in the countryside.
Abstract: Urbanization refers to the complex interaction of different processes which transform landscapes formed by rural life styles into urban like ones. Urbanization causes profound changes in the ecological functioning of the landscape and gradually results in a changing spatial structure, i.e. forms new landscape patterns. The existing cities and urban network form the framework for this change, which is affecting increasingly larger areas in the countryside. Urbanization is mainly studied from social and economical viewpoints. Urban planners think about optimization of the land use and about aesthetics when reshaping the environment. Landscape ecology is lacking in urban planning because of different goals and concepts, but mostly because of missing significant information about these highly dynamical landscapes.

406 citations


01 Jan 2000
TL;DR: The first French geographical accounts of (intraand peri-) urban agriculture (UA) were published on Central Africa in the 1960s, scattered and isolated UA surveys by individual social scientists (e.g. Egziabher et al. 1994) have gradually been giving way to institutional projects led by multidisciplinary teams as mentioned in this paper.
Abstract: Ever since the first French geographical accounts of (intraand peri-) urban agriculture (UA) were published on Central Africa in the 1960s, scattered and isolated UA surveys by individual social scientists (e.g. Egziabher et al. 1994) have gradually been giving way to institutional projects led by multidisciplinary teams. As a result, more and better information is now available on a larger number of regions, countries and cities around the world. Over the same period, public initiatives pioneered by few local and national governments have been followed by more widespread awareness on the part of local authorities, in their regional and global fora, for the growth and potential of agriculture in and around cities. More urban governments are now seeking to exchange policy and technical experiences to better deal with a spreading phenomenon in their own city.

384 citations


Journal ArticleDOI
TL;DR: In this paper, the long-term urban climate effects are detectable from an analysis of the GHCN (Global Historical Climate Network) database and a comparison of urban versus rural temperature changes with decadal population data.
Abstract: Two Long-Term Ecological Research (LTER) sites now include urban areas (Baltimore, Maryland and Phoenix, Arizona). A goal of LTER in these cities is to blend physical and social science investigations to better understand urban ecological change. Research monitoring programs are under- way to investigate the effects of urbanization on ecosystems. Climate changes in these urban areas reflect the expanding population and associated land surface modifications. Long-term urban climate effects are detectable from an analysis of the GHCN (Global Historical Climate Network) database and a comparison of urban versus rural temperature changes with decadal population data. The relation of the urban versus rural minimum temperatures (⌉Tminu-r) to population changes is pronounced and non-linear over time for both cities. The ⌉Tmaxu-r data show no well-defined temporal trends.

326 citations


Journal ArticleDOI
TL;DR: Results indicate that, despite regional differences, in nearly all cases the species studied flower earlier in urbanised areas than in the corresponding rural areas, and rural areas showed a higher trend towards an earlier flowering than did urban areas for the period from 1980 to 1995.
Abstract: In order to examine the impacts of both large-scale and small-scale climate changes (urban climate effect) on the development of plants, long-term observations of four spring phenophases from ten central European regions (Hamburg, Berlin, Cologne, Frankfurt, Munich, Prague, Vienna, Zurich, Basle and Chur) were analysed. The objective of this study was to identify and compare the differences in the starting dates of the pre-spring phenophases, the beginning of flowering of the snowdrop (Galanthus nivalis) and forsythia (Forsythia sp.), and of the full-spring phenophases, the beginning of flowering of the sweet cherry (Prunus avium) and apple (Malus domestica), in urban and rural areas. The results indicate that, despite regional differences, in nearly all cases the species studied flower earlier in urbanised areas than in the corresponding rural areas. The forcing in urban areas was about 4 days for the pre-spring phenophases and about 2 days for the full-spring phenophases. The analysis of trends for the period from 1951 to 1995 showed tendencies towards an earlier flowering in all regions, but only 22% were significant at the 5% level. The trends for the period from 1980 to 1995 were much stronger for all regions and phases: the pre-spring phenophases on average became earlier by 13.9 days/decade in the urban areas and 15.3 days/decade in the rural areas, while the full-spring phenophases were 6.7 days earlier/decade in the urban areas and 9.1 days/decade earlier in the rural areas. Thus rural areas showed a higher trend towards an earlier flowering than did urban areas for the period from 1980 to 1995. However, these trends, especially for the pre-spring phenophases, turned out to be extremely variable.

250 citations


Journal Article
TL;DR: In this paper, the authors examined trends of urban population change in less developed and more developed regions and discussed policies to manage cities and urban growth, incorporating concepts of the city that have recently emerged in urban population studies.
Abstract: Managing urban population change will be one of the worlds most important challenges in the next few decades. In less developed countries where 80% of the worlds population resides central issues will be on how to cope with an unprecedented increase in the number of people living in urban areas and the growing concentration of these urbanites in large cities with millions of residents. In more developed countries such as the US the urban feature involve the dealing with complex changes in the composition of urban populations. This issue of the Population Bulletin examines trends of urban population change in less developed and more developed regions. Among more developed countries particular attention is given to the US. The report describes the demographic sources of urban growth in less developed countries traits that distinguish urban from rural populations in these countries and some of the critical challenges posed by the urban demographic revolution. Policies to manage cities and urban growth are discussed; incorporating concepts of the city that have recently emerged in urban population studies.

239 citations


01 Jan 2000
TL;DR: In one century, global urban populations have expanded from 15 to 50% of the total, which itself has gone up from 1.5 to nearly 6 billion as mentioned in this paper, and the size of modern cities in terms of numbers as well as physical scale is unprecedented.
Abstract: At the end of the 20 century, humanity is involved in an unprecedented experiment: we are turning ourselves into an urban species. Large cities, not villages and towns, are becoming our main habitat. Urban growth is changing the face of the earth and the condition of humanity. In one century, global urban populations have expanded from 15 to 50% of the total, which itself has gone up from 1.5 to nearly 6 billion. The size of modern cities in terms of numbers as well as physical scale is unprecedented. In 1800, there was only one city with a million people, London. By 1990, the world's 100 largest cities accommodated 540 million people and 220 million people lived in the 20 largest cities, megacities of over 10 million people, some extending to hundreds of thousands of hectares.

219 citations


Journal ArticleDOI
TL;DR: In this article, the authors show that land use patterns of urban and rural character next to each other in Asian mega-cities have not achieved significant success in controlling air and water pollution and lack of adequate urban infrastructure.

211 citations


Book
01 Jan 2000
TL;DR: The first national assessment of urban forest resources in the United States and details variations in urbanization and urban tree cover across United States by state, county, and individual urban area as mentioned in this paper.
Abstract: Urban areas (cities, towns, villages, etc) cover 35 percent of the 48 conterminous states and contain more than 75 percent of the population urban areas, about 38 billion trees cover 271 percent of the land On a broader scale, metropolitan areas (urban counties) cover 245 percent of the conterminous United States and contain 744 billion trees that cover 334 percent of these counties Between 1950 and 1990, metropolitan areas nearly tripled in size; urban areas doubled in size over the past 20 to 25 years This report is the first national assessment of urban forest resources in the United States and details variations in urbanization and urban tree cover across the United States by state, county, and individual urban area It illustrates local-scale variation, complexity, and connectedness of the urban forest resource and how this resource changes through time in response to a wide range of powerful forces The report concludes by outlining future areas of emphasis that will facilitate comprehensive, adaptive, and sustainable urban forest management and improve environmental quality, enhance human health, and connect people with ecosystems in the 21st century

169 citations


Journal ArticleDOI
TL;DR: In this paper, the authors propose the addition of three social dimensions to characteristics defining urban gradients: landuse, land management effort, and historical context, which correspond with major types of social activities that modify the physical environment.
Abstract: Urban ecosystems are complex mosaics in which the biophysical characteristics are transformed over time by a concentrated, diverse set of human activities. Understanding their complexity requires the continuing development of interdisciplinary approaches. The use of gradient approaches has pointed towards the need to examine in greater detail the roles of human influences. In this paper, I propose the addition of three social dimensions to characteristics defining urban gradients: landuse, land management effort, and historical context. These dimensions correspond with major types of social activities that modify the physical environment. They are intended to augment research by explicitly elaborating on the social factors contributing to the variation along the complex, indirect gradients that typify urban areas. The diversity of urban landuses has numerous influences, obvious and subtle, on the complex urban land gradients. Incorporating new information on historical and spatial characteristics of management practices supports more direct fine-scale analyses of the impact of human activities on the environment. This path of inquiry also requires engaging in more detailed research on historical dimensions of urban development in conjunction with biophysical analyses. Examples from Columbia, South Carolina, illustrate the ways that social and historical processes contribute to urban ecology.

Book
01 May 2000
TL;DR: In this article, the authors examined the role of land re-adjustment (LR) in shaping patterns of urban development in the rapidly growing northern suburbs of Tokyo in Saitama prefecture.
Abstract: Land Readjustment (LR) is a land development technique used in many countries around the world including Germany, Sweden, Japan, Taiwan and Korea. In essence it is a method whereby an irregular pattern of agricultural land holdings is re-arranged into regular building plots and equipped with basic urban infrastructure such as roads and drains. A percentage of each landowner’s holding is contributed to provide land for roads and parks, and for some plots to sell to pay the costs of the project. Its use has been particularly widespread in Japan where it is responsible for some 30% of the existing urban area, and is commonly referred to as ‘The Mother of City Planning’ (Toshi Keikaku no Haha). LR has for 20 years also been the focus of an international effort to introduce the technique to the developing countries of South East Asia. Although there is now a large literature on Japanese LR as a result of that project, however, virtually all of that literature focusses on practical aspects of how to implement projects, and on case studies of individual projects. Little attention has been paid to the role of LR in Japanese urban growth and urban planning at a city or regional scale, although such an examination is necessary to understanding LR in Japan, and Japanese urbanisation and urban planning more generally. The present research examines the role of LR in shaping patterns of urban development in the rapidly growing northern suburbs of Tokyo in Saitama prefecture. In particular, the claim commonly made by Japanese writers that LR prevents urban sprawl is examined. Sprawl and its prevention have long been a preoccupation of both Western and Japanese urban planners for aesthetic and efficiency reasons. However, it has recently gained importance as the critical interconnections between urban form and urban travel patterns, and greenhouse gas emissions and global warming have become more widely recognised. The case studies examine the role of LR in land development and urban growth at the regional scale (Saitama prefecture) and at the local scale (Urawa, Omiya and Ageo cities). GIS mapping and analysis of the case study areas, and interviews with planners and participants are used to examine the role and impacts of LR projects in suburban land development in Japan. The research suggests that while there are various impacts of LR projects because they are so widely used, in a range of different contexts, it is fair to say that LR projects contribute to increased sprawl at the regional scale, while largely failing to prevent it at the local scale.


Journal ArticleDOI
TL;DR: The authors describes the conflict between agriculture and urban development in the Pampa Ondulada, the eco-region where the city of Buenos Aires is located and which is one of the world's richest a...
Abstract: This paper describes the conflict between agriculture and urban development in the Pampa Ondulada, the eco-region where the city of Buenos Aires is located and which is one of the world’s richest a...


Journal ArticleDOI
TL;DR: The presence and recorded the characteristics of an urban heat island in the small coastal city of Aveiro, Portugal, developed through the scheduled measurements of air temperature and the analysis of the geographical, meteorological and urban conditions.
Abstract: This project arose from the need to study the phenomenon of the urban heat island, since only by recognising this phenomenon can we moderate it to improve the human and urban environments. Not only big cities develop urban heat islands. This study detected the presence and recorded the characteristics of an urban heat island in the small coastal city of Aveiro, Portugal. The study was developed through the scheduled measurements of air temperature and the analysis of the geographical, meteorological and urban conditions. The form and intensity of Aveiro’s heat island are a response to the interaction of three principal factors: the urban morphology (the hottest zones in the city are those with the tallest and the highest density of buildings, without green spaces and with intense generation of heat from traffic, commerce and services); the meteorological conditions (the intensity of the island is at its maximum when the sky is totally clear and there is no wind, and at its minimum in those situations when there is atmospheric instability, such as wind, cloud and precipitation); and the proximity of the coastal lagoon (which borders the city to the west and northwest and moderates seasonal temperatures. The urban heat island influences the comfort and health of its inhabitants, thus urban planning is very important in the moderation and prevention of this phenomenon.

Journal ArticleDOI
TL;DR: In this paper, the authors used an extension of the Carlino and Mills and Boarnet models to test for city size and growth influences on rural population and employment changes.

19 Aug 2000
TL;DR: In this paper, the authors highlight the importance of urban trees and related vegetation in and around densely populated areas in both industrialized and developing countries and highlight the implications of urbanization for development cooperation, benefits of urban forests, poverty alleviation, innovative publicprivate partnerships and multiresource management.
Abstract: Urban dwellers are increasingly recognizing and articulating the importance of urban forests as a vital component of the urban landscape, infrastructure and quality of life. Municipalities together with diverse stakeholders around the world have launched often quite ambitious urban forestry programmes. Much progress has been achieved in urban forestry research and development in industrialized countries. However, multipurpose urban forestry in developing countries is still in its infancy. In addition, forestry work is conspicuously absent from urban development cooperation initiatives, despite the accelerated urbanization process taking place in developing countries. This article highlights the importance of urban trees and related vegetation in and around densely populated areas in both industrialized and developing countries. The focus is on implications of urbanization for development cooperation, benefits of urban forests, poverty alleviation, innovative publicprivate partnerships and multiresource management. URBANIZATION AND ITS CONSEQUENCES Accelerated urban growth in developing countries Urbanization is a worldwide trend. In 1995 some 73 percent of Latin Americans lived in cities, making the region roughly as urbanized as Europe and North America. In Asia and Africa onethird of the total population was classified as urban. The new millennium will be an urban millennium. Urban areas in developing countries will account for nearly 90 percent of the projected world population increase of 2 700 million people between 1995 and 2030. By the year 2030, almost 85 percent of Latin Americans and 50 percent of all Africans and Asians will live in cities. The most explosive urban growth is expected in Africa and Asia. Asia will have the largest urban population in the world, with almost twice as many people living in cities as in Africa and Latin America combined (UN, 1998). Peri-urban areas have the highest growth rates and receive up to 70 percent of the migrants from rural areas as well as migrants from the city itself. These areas are in most ways integrated with the city, yet most forestry projects in peri-urban areas are designed as rural projects. If not integrated into urban planning, they are doomed to fail.

01 Jan 2000
TL;DR: In this paper, the authors present information about the climatic design of buildings today, using passive techniques and give recommendations on how to carry out the design in different climates, but urban climate is also considered.
Abstract: Buildings in developing countries are often designed without taking sufficient account of the climate. Factors such as the urban surroundings or site characteristics, orientation and architectural design of the building, choice of building materials, etc are not given enough importance. Consequently buildings often have a poor indoor climate, which affects comfort, health and efficiency. The problem is found in dwellings as well as workplaces or public buildings, such as schools and hospitals. As living standards rise people want to install heating and/or cooling equipment to improve thermal comfort. For buildings not adapted to the climate, the amount of energy to run the equipment, and its cost, will be excessively high, and it will have a negative impact on the environment. A good, or at least acceptable, indoor climate can often be achieved with little or no extra input of energy. Apart from a general lack of norms and regulations, one reason why buildings are poorly adapted to the climate is lack of knowledge among architects, planners and engineers. Central concepts such as thermal capacity and thermal insulation are often misunderstood. The knowledge from traditional construction, which was fairly well adapted to the climate, is often lost or difficult to translate to modern techniques and society. The objective of this study is to present information about the climatic design of buildings today, using passive techniques. It explains central concepts in climatic design and gives recommendations on how to carry out the design in different climates. The focus is on building design, but urban climate is also considered. Ways to gain more knowledge are presented and illustrated with a case study. This study was carried out as a desk study. The work is based on: compilation of the author’s experience as a designer and researcher in North Africa, South-East Asia and Latin America, survey of the literature survey on experiences in other regions, synthesis of personal and collected information. Each building site offers its own conditions for a good climatic design, and it is the task of the designer to exploit the positive and avoid the negative. Even if it is impossible to give any general rules, recommendations in the form of a checklist are summarized for each main climate type.

Journal ArticleDOI
TL;DR: In the Brazilian Amazon during the 1980s, urban population growth outstripped rural growth, and by 1991, most of the region's population resided in urban areas, which resulted in high pollution as mentioned in this paper.
Abstract: In the Brazilian Amazon during the 1980s,urban population growth outstripped rural growth, andby 1991, most of the region's population resided inurban areas. Much of this urban growth involvedestablishment of unplanned housing with inadequateinfrastructure, which resulted in rising pollution. This paper compares indicators of environmentalquality in urban populations of the Amazon in 1980 and1991, and among different kinds of urban populationsin 1991. The results show that environmental qualityin the region deteriorated during the 1980s as theproduction of and exposure to environmental hazardsrose while resources to ward off hazards eroded. Thefindings also show that environmental quality wasparticularly poor in more rapidly growing urbancenters. The urban Amazon may not afford an adequatestandard of living and this may generate out-migrationfrom the region.

01 Jan 2000
TL;DR: The Mexico City metropolitan zone (MCMZ) covers an area of 7,860 km and includes the Federal District and 54 municipalities as mentioned in this paper and is located in the Valley of Mexico, at the centre of the Mexican highlands It extends over 1,479 km, has an average altitude of 2,238 m above sea level and is surrounded by mountains of up to 3880 m.
Abstract: The Mexico City Metropolitan Zone (MCMZ) covers an area of 7,860 km and includes the Federal District and 54 municipalities (Programa 1983 cited by Delgado 1994) Mexico City (Federal District) is located in the Valley of Mexico, at the centre of the Mexican highlands It extends over 1,479 km, has an average altitude of 2,238 m above sea level and is surrounded by mountains of up to 3880 m The main soil types are litosoles, andosoles, feozem, regosoles and solonchak (CETENAL 1977) The climate is temperate, with summer rains Mean temperature ranges between 18oC and 24oC, and average annual rainfall ranges between 100 and 1,400 mm

Journal ArticleDOI
TL;DR: In this article, numerical simulations of thermal field variation due to land use changes, such as the reduction of the lacustrine system and the growth of the urban area, in the Basin of Mexico are presented.
Abstract: Numerical simulations of thermal field variation due to land use changes, such as the reduction of the lacustrine system and the growth of the urban area, in the Basin of Mexico are presented. It is shown that the historically recorded warming in the basin could be attributed, not only to the growth of the urban area, but more importantly to the drastic reduction in the lacustrine system that existed in the basin.

Journal ArticleDOI
TL;DR: In this article, the authors analyzed the sensitivity of the urban water sector in the Southwest to climatic variability and provided an essential foundation for effective evaluation of the region's sensitivity to longer term climate change.
Abstract: Stresses on water resources in the Southwest take many forms and emanate from many different sources, among which are complex institutional arrangements, significant areal and temporal climatic variability, and high urban growth rates. Further challenges to managing supply and demand in this water-scarce region are posed by environmental, social, and legal differences within and between the individual urban areas. Analysis of the sensitivity of the urban water sector in the Southwest to climatic variability requires careful consideration of these factors. Such analysis, in turn, provides an essential foundation for effective evaluation of the region's sensitivity to longer term climate change.

Journal ArticleDOI
TL;DR: In this article, a multi-temporal analysis of mainly the limits of the built up urban areas and their surrounding land cover is used to study the manner, rate, extent and impact of the expansion of the urban cluster of Rosetta City.
Abstract: Unplanned urban expansion of the new urban cluster of Rosetta City, Egypt is reaching a critical stage. This unplanned expansion of slum areas threatens the land on which the high quality palm trees, by which Rosetta region is known, are cultivated. This research is concerned with studying the manner, rate, extent and impact of the expansion of the urban cluster of Rosetta City. A multi-temporal analysis of mainly the limits of the built up urban areas and their surrounding land cover is the main evaluation technique. By using Geographic Information Systems, it was possible to study the geographic base of the concerned area. An increase in area of the urban clusters of about 0.1 km2 occurred from 1917–1945, and a second increase of over 0.07 km2 occurred from 1945–1963. Just after the end of the Second World War, an abrupt increase took place in 1963–1993 that reached 1.7 km2. The majority of all the urban expansion was unplanned. By studying the topographic map of Rosetta city and the urban clusters on the western bank of the river Nile, it was found that most of the urban conglomeration of the city is located on relatively elevated land. The western part of the urban area is of an elevation varying around 5.0 m, and inclining with moderate slope towards the eastern edge of the city adjacent to the river Nile. The urban expansion on inclined land has caused severe problems with the sanitary drainage, as the city lacks any sanitary drainage systems. Sanitary drainage currently operates through precipitation trenches. Sanitary sewage gather beneath the ground forming continuos streams which reach the basements of many of the monuments present.

01 Jan 2000
TL;DR: The management of urban forests has important implications for the health and well-being of the residents of urban and urbanizing areas; but its influence on the forest management extends well beyond the boundaries of urban areas as mentioned in this paper.
Abstract: Urban forest management promises to play a critical role in the management of .... our nation's forest resources in the 21st century. Urban forests are significant and diverse ecosystems with intricate connections among their physical, biological, and social components; as well as with other elements of urban and natural resource systems. Urban forests are also dynamic systems, shaped by the relatively slow growth and development of trees in the context of rapidly changing urban environments. To sustain forest structure, health, and benefits over the long-term, comprehensive, and adaptive management approaches are needed. The management of urban forests has important implications for the health and well-being of the residents of urban and urbanizing areas; but its influence on the forest management extends well beyond the boundaries of urbanizing areas.

01 Jan 2000
TL;DR: Wang et al. as mentioned in this paper explored how to exact residential information from topographic map and remote sensing images at first, then it studies the spatial pattern and change characters of urban and rural residential areas in Changjiang River Delta according to fractal theory.
Abstract: Changjiang River Delta is a developed and rich area in China, which has become one of the most crowded urban and rural residential areas. From the late 1970s, urbanization process in Changjiang River Delta has been quickened greatly, which resulted in number increasing and spatial expansion of urban and rural settlements. In the 1990s urbanization level in Changjiang River Delta has been about 50%, and many cities such as Suzhou, Wuxi and Changzhou have become large cities with a population of more than one million, many small cities have also become medium sized cities with a population of 100 thousand to 200 thousand. At the same time, the most typical economic development character in Changjiang River Delta is prosperous rural industrial enterprises. So spatial pattern of urban and rural residential areas has changed greatly, which was reflected mainly in spatial diffusion. Along with the above mentioned spatial changes, the problem of how can we realize sustainable development of urban and rural residential areas in scale, form, pattern and function in a certain spatial and temporal range should be paid attention to. In light with above mentioned problem, we need to analyze urban and rural residential spatial pattern and find inner basic law of spatial pattern change. But the basics to study spatial pattern change lie in how to extract information of urban and rural residential areas rapidly and exactly. The paper explores how to exact residential information from topographic map and remote sensing images at first, then it studies the spatial pattern and change characters of urban and rural residential areas in Changjiang River Delta according to fractal theory.

Journal Article
TL;DR: In this article, two new enhanced versions of the UCLM (Urban Canopy Layer Model) model, Landsat/Thematic Mapper data sets and meteorological data collected over a square area 30 km of side including Milan and its hinterland.
Abstract: The study of the urban heat island has been carried out through two new enhanced versions of the UCLM (Urban Canopy Layer Model) model, Landsat/Thematic Mapper data sets and meteorological data collected over a square area 30 km of side including Milan and its hinterland. The urban climate can be described in different summer and winter radiative settings. The input data are divided into two classes: 1) parameters related to urban and rural local properties (albedo and emissivity, vegetation index NDVI, surface roughness length, land cover...); 2) meteorological data related to the general synoptic conditions. The bulk system of the model is made up of four independent equations expressed in terms of four unknowns, i.e., the temperature values at ground level, canopy level and reference level (100 m) and relative humidity within the urban structure. The study area is divided by a regular square mesh of variable dimension (from 30 m to 1500 m); both the input and output data are average cell values. UCLM30 and UCLM60 calculates the temperature excess as well as the turbulent heat exchanges and the heat storage in the urban canopy as a function of the radiative and dynamic forcing. As can be observed in reality, the model shows that in summer the highest urban heating occurs in early morning and after sunset and that, in extreme conditions, the temperature can be up to 8°C warmer in town than in the nearby rural lands.

Journal ArticleDOI
TL;DR: In this article, a new definition of the urban forest is proposed that recognizes the need for an ecosystem approach to urban forest management and the integral role that humans play in that ecosystem.
Abstract: The pressures created by urban sprawl are leading to a reduction in forested land in Canada and North America. Poorly controlled land-use planning contributes to the haphazard urbanization of many small communities within commuting distance of major urban centres. Urban forests are largely ignored as an asset and the potential benefits they can offer to communities are often not acknowledged in the planning process. Relatively few communities across Canada have any form of urban forest management. A new definition of the urban forest is proposed that recognizes the need for an ecosystem approach to urban forest management and the integral role that humans play in that ecosystem. To facilitate the implementation of urban forest management plans in small communities, a simple strategic planning framework is presented. Using this approach, many small towns can maintain their rural character and benefit from a wealth of environmental, social and economic benefits. Key words: urban forestry, community planning...


Journal ArticleDOI
TL;DR: In this article, the authors discuss urban agricultural functions and their changes in the metropolitan area of Tokyo prefecture and demonstrate the multi-functional system of urban agriculture with a case study in the Nishi-Ooizumi area of Nerima ward.
Abstract: In this paper, the author discusses urban agriculturalfunctions and their changes in the metropolitan area of Tokyo prefecture. Following this discussion, the author analyzes some factors that have caused changes infunctions of urban agriculture, and she demonstrates the multi-functional system of urban agriculture with a case study in the Nishi-Ooizumi area of Nerima ward. Nerima is located in the northwestern suburbs of metropolitan Tokyo about ten kilometersfrom the metropolitan center, and Nishi-Ooizumi is located in the northwestern part of the ward. Although this area has had good accessibility to the metropolitan center in terms of commuting, agriculture has continued to be practiced since the 1970s. Productive green land, an importantfactor in the sustainability of urban agriculture, comprised 66.4 percent of all thefarmland in Nerima ward in 1997.Based onfield surveys and land use maps, somefunctions in terms of both agriculture andfarmland wereidentified in Nishi-Ooizumi area. They have beenclassified intofive types: agricultural production, amenity and environment, disaster prevention, leisure activity, and land supply. Changes in these functions have been divided into threeperiods: urban fringe agriculture, early urban agriculture, and growth of urban agriculture. In each period, the author considers the interaction among functions and the conditions affecting them.In the period of urbanfringe agriculture, before the early 1960s, farmland was the dominant use of land in the Nishi-Ooizumi area, and agriculture there was mono-functional and belonged to the agricultural production function. In the period of early urban agriculture, the latter 1960s and the 1970s, the land supplyfunction dominated because of high economic growth and the enforcement of the City Planning Act, but because some agriculture in the area fell under the agricultural production function, there was a dual functional system at this time. In the period of urban agriculture growth, during andafter the 1980s, agriculture continued tofall into the agricultural production and land supply functions, but the other three functions-amenity and environment, disaster prevention, and leisure-were introduced at this time. Thus, thesefivefunctions have interacted with eachother and created a multi-functional system in the last two decades. This multifunctionalization was caused by rising land prices, a review of measures against calamities after the Hanshin earthquake in 1995, and environmental conservation.The land supply function has been regarded as detrimental for sustainable urban agriculture because it also appropriated land for nonagricultural use and thus contributed to the decline of agriculture. Nevertheless, urban farmland also performed an important function in getting funds for farmers. Accordingly, sustainability of urban agriculture depended on the land supply function.In summary, the differences in function in each period were caused by the influence of enforcement of laws, business conditions, and urbanization of the area. Although urban agriculture originally was mono-functional and fell under the agricultural production function, it came to include other functions as a dual-functional and then a multi-functional system.