Urban air quality
Urban air quality
复制标题
DOI：
10.1016/s1352-2310(99)00290-3
复制
发表时间：
1999-12-01
影响因子：
5
通讯作者：
Fenger, J
中科院分区：
文献类型：
--
作者：
Fenger, J
自 1950 年以来，世界人口增加了一倍以上，全球汽车数量增加了 10 倍。同一时期，居住在城市地区的人口比例增加了 4 倍。到 2000 年，这一数字将接近世界人口的一半。大约20个城市地区的人口将超过1000万。从较长时期来看，主要城市的污染在建成阶段往往会增加，经过一个峰值后，随着减排策略的制定，污染会再次减少。在工业化的西方世界，城市空气污染在某些方面已进入最后阶段，二氧化硫和烟尘水平已有效降低。然而，近几十年来，交通流量的增加已将人们的注意力转向氮氧化物、有机化合物和小颗粒。在一些城市，光化学空气污染是一个重要的城市问题，但在欧洲北部，这是一个大规模的现象，城市街道的臭氧水平通常低于农村地区。东欧的城市已经（并且在许多情况下仍然）受到严重污染。经过最近的政治动荡、短暂的衰退以及随后新技术的引入，情况似乎有所改善。然而，私家车数量的不断增加是一个新问题。在大多数发展中国家，快速的城市化迄今已导致增长失控和环境恶化。这里的空气污染水平在许多方面仍在上升。除了当地空气污染的来源之外，城市活动也是跨界污染和全球温室气体浓度不断上升的重要因素。通过引入更清洁、更节能的技术来解决城市问题的尝试通常会对这些大规模问题产生有益的影响。另一方面，基于城市规划并分散活动的尝试可能会产生更多的交通，因此可能会产生相反的效果。 (C) 1999 Elsevier Science Ltd. 保留所有权利。
Since 1950 the world population has more than doubled, and the global number of cars has increased by a factor of 10. In the same period the fraction of people living in urban areas has increased by a factor of 4. In year 2000 this will amount to nearly half of the world population. About 20 urban regions will each have populations above 10 million people.Seen over longer periods, pollution in major cities tends to increase during the built up phase, they pass through a maximum and are then again reduced, as abatement strategies are developed. In the industrialised western world urban air pollution is in some respects in the last stage with effectively reduced levers of sulphur dioxide and soot. In recent decades however, the increasing traffic has switched the attention to nitrogen oxides, organic compounds and small particles. In some cities photochemical air pollution is an important urban problem, but in the northern part of Europe it is a large-scale phenomenon, with ozone levels in urban streets being normally lower than in rural areas. Cities in Eastern Europe have been (and in many cases still are) heavily polluted. After the recent political upheaval, followed by a temporary recession and a subsequent introduction of new technologies, the situation appears to improve. However, the rising number of private cars is an emerging problem. In most developing countries the rapid urbanisation has so far resulted in uncontrolled growth and deteriorating environment. Air pollution levels are here still rising on many fronts.Apart from being sources of local air pollution, urban activities are significant contributors to transboundary pollution and to the rising global concentrations of greenhouse gasses. Attempts to solve urban problems by introducing cleaner, more energy-efficient technologies will generally have a beneficial impact on these large-scale problems. Attempts based on city planning with a spreading of the activities, on the other hand, may generate more traffic and may thus have the opposite effect. (C) 1999 Elsevier Science Ltd. All rights reserved.