TY - THES A1 - Schrauth, Philipp T1 - Agglomerations, air quality and urban transformation T1 - Ballungsräume, Luftqualität und städtischer Wandel N2 - Die vorliegende Dissertation stellt empirische Untersuchungen über den Zusammenhang von städtischem Leben und dessen ökonomische Kosten, insbesondere für die Umwelt, an. Dabei werden zum einen bestehende Forschungslücken des Einflusses von Bevölkerungsdichte auf die Luftqualität geschlossen und zum anderen innovative Politikmaßnahmen im Verkehrsbereich untersucht, die Ballungsräume nachhaltiger gestalten sollen. Im Zentrum der Betrachtungen stehen Luftverschmutzung, Staus und Verkehrsunfälle, die für Fragen der allgemeinen Wohlfahrt bedeutend sind und erhebliche Kostenfaktoren für urbanes Leben darstellen. Von ihnen ist ein beträchtlicher Anteil der Weltbevölkerung betroffen. Während im Jahr 2018 bereits 55% der Menschen weltweit in Städten lebten, soll dieser Anteil bis zum Jahr 2050 ungefähr 68% betragen. Die vier in sich geschlossenen Kapitel dieser Arbeit lassen sich in zwei Abschnitte aufteilen: In den Kapiteln 2 und 3 werden neue kausale Erkenntnisse über das komplexe Zusammenspiel von städtischen Strukturen und Luftverschmutzung erbracht. Kapitel 4 und 5 untersuchen anschließend politische Maßnahmen zur Förderung nicht-motorisierter Verkehrsmittel und deren Einfluss auf Luftqualität sowie Staugeschehen und Verkehrsunfälle. N2 - The present dissertation conducts empirical research on the relationship between urban life and its economic costs, especially for the environment. On the one hand, existing gaps in research on the influence of population density on air quality are closed and, on the other hand, innovative policy measures in the transport sector are examined that are intended to make metropolitan areas more sustainable. The focus is on air pollution, congestion and traffic accidents, which are important for general welfare issues and represent significant cost factors for urban life. They affect a significant proportion of the world's population. While 55% of the world's people already lived in cities in 2018, this share is expected to reach approximately 68% by 2050. The four self-contained chapters of this thesis can be divided into two sections: Chapters 2 and 3 provide new causal insights into the complex interplay between urban structures and air pollution. Chapters 4 and 5 then examine policy measures to promote non-motorised transport and their influence on air quality as well as congestion and traffic accidents. KW - air quality KW - urban transformation KW - public transport KW - cycling KW - population density KW - Luftqualität KW - Radverkehr KW - Bevölkerungsdichte KW - Öffentliche Verkehrsmittel KW - städtischer Wandel KW - Verkehr KW - traffic KW - Städte KW - cities KW - Umwelt KW - environment Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-586087 ER - TY - RPRT A1 - Borck, Rainald A1 - Schrauth, Philipp T1 - Urban pollution BT - A global perspective T2 - CEPA Discussion Papers N2 - We use worldwide satellite data to analyse how population size and density affect urban pollution. We find that density significantly increases pollution exposure. Looking only at urban areas, we find that population size affects exposure more than density. Moreover, the effect is driven mostly by population commuting to core cities rather than the core city population itself. We analyse heterogeneity by geography and income levels. By and large, the influence of population on pollution is greatest in Asia and middle-income countries. A counterfactual simulation shows that PM2.5 exposure would fall by up to 36% and NO2 exposure up to 53% if within countries population size were equalized across all cities. T3 - CEPA Discussion Papers - 60 KW - population density KW - air pollution KW - gridded data Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-572049 SN - 2628-653X IS - 60 ER - TY - JOUR A1 - Li, Yunfei A1 - Rybski, Diego A1 - Kropp, Jürgen T1 - Singularity cities JF - Environment and planning. B, Urban analytics and city science N2 - We propose an upgraded gravitational model which provides population counts beyond the binary (urban/non-urban) city simulations. Numerically studying the model output, we find that the radial population density gradients follow power-laws where the exponent is related to the preset gravity exponent gamma. Similarly, the urban fraction decays exponentially, again determined by gamma. The population density gradient can be related to radial fractality and it turns out that the typical exponents imply that cities are basically zero-dimensional. Increasing the gravity exponent leads to extreme compactness and the loss of radial symmetry. We study the shape of the major central cluster by means of another three fractal dimensions and find that overall its fractality is dominated by the size and the influence of gamma is minor. The fundamental allometry, between population and area of the major central cluster, is related to the gravity exponent but restricted to the case of higher densities in large cities. We argue that cities are shaped by power-law proximity. We complement the numerical analysis by economics arguments employing travel costs as well as housing rent determined by supply and demand. Our work contributes to the understanding of gravitational effects, radial gradients, and urban morphology. The model allows to generate and investigate city structures under laboratory conditions. KW - Gravity models KW - population density KW - urban fraction KW - fractal geometry Y1 - 2021 U6 - https://doi.org/10.1177/2399808319843534 SN - 2399-8083 SN - 2399-8091 VL - 48 IS - 1 SP - 43 EP - 59 PB - Sage Publ. CY - London ER - TY - JOUR A1 - Rybak, Alexander A1 - Bents, Dominik A1 - Krüger, Johanna A1 - Groth, Detlef T1 - The end of the secular trend in Norway BT - spatial trends in body height of Norwegian conscripts in the 19th, 20th and 21st century JF - Journal of biological and clinical anthropology : Anthropologischer Anzeiger ; Mitteilungsorgan der Gesellschaft für Anthropologie N2 - Aim: We aimed to examine the distribution and secular changes of conscript body height in the geographic network of Norway since 1878 and to study its association with the degree of urbanization, and population density. Material and methods: Data on body height of Norwegian military conscripts were provided by the Statistics Norway Department (SSB). The sample comprised eight cohorts with the following measurement years: 1st 1877, 1878 and 1880, 2nd 18951897, 3rd 1915-1917, 4th 1935-1937, 5th 1955-1957, 6th 1975-1977, 7th 1995-1997, and 8th 2009-2011. For determining neighborhood correlations, a network was created consisting of neighboring counties, sharing a common border. Results: Average body height of Norwegian men increased by 10.9 cm between 1878 and 2010, but this trend was heterogeneous. Some counties increased by more than 1 cm per decade (Finmark) others by only 7 mm per decade (Sor-Trondelag). Urban counties and counties with higher population density showed stronger height trends than rural counties. The largest spread in body height between the various counties was observed in 1936 when for the first time people living in the more urban counties got taller than rural people. The height advantage of urban counties however, disappeared after 1996. At this time, also the secular trend in height had come to a halt. The secular trend in height had become obvious after the dissolution of the union between Norway and Sweden in 1905 and World War I, and was strongest between 1936 and 1956. During this period maximum between-county heterogeneity in height existed with body height differences of more than 6 cm between the tallest and the shortest county. The end of this period was characterized by social democratic reforms that flattened the income distribution, eliminated poverty, and ensured social services after World War II. Conclusion: The temporal coincidence between the trends in height, the degree of urbanization and the onset of the political transition of Norway from a Swedish province into an independent democratic wealthy modern European state after World War I and particularly after World War II, and the abatement of this trend after this period of transition had stabilized, suggest social and political components interfering with the regulation of physical growth in humans. KW - male body height KW - degree of urbanization KW - population density KW - Norway Y1 - 2020 U6 - https://doi.org/10.1127/anthranz/2020/1254 SN - 0003-5548 VL - 77 IS - 5 SP - 415 EP - 421 PB - Schweizerbart CY - Stuttgart ER - TY - RPRT A1 - Borck, Rainald A1 - Schrauth, Philipp T1 - Population density and urban air quality T2 - CEPA Discussion Papers N2 - We use panel data from Germany to analyze the effect of population density on urban air pollution (nitrogen oxides, particulate matter and ozone). To address unobserved heterogeneity and omitted variables, we present long difference/fixed effects estimates and instrumental variables estimates, using historical population and soil quality as instruments. Our preferred estimates imply that a one-standard deviation increase in population density increases air pollution by 3-12%. T3 - CEPA Discussion Papers - 8 KW - population density KW - air pollution Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-427719 SN - 2628-653X IS - 8 ER - TY - JOUR A1 - Thieken, Annegret A1 - Apel, Heiko A1 - Merz, Bruno T1 - Assessing the probability of large-scale flood loss events: a case study for the river Rhine, Germany JF - Journal of flood risk management N2 - Flood risk analyses are often estimated assuming the same flood intensity along the river reach under study, i.e. discharges are calculated for a number of return periods T, e.g. 10 or 100 years, at several streamflow gauges. T-year discharges are regionalised and then transferred into T-year water levels, inundated areas and impacts. This approach assumes that (1) flood scenarios are homogeneous throughout a river basin, and (2) the T-year damage corresponds to the T-year discharge. Using a reach at the river Rhine, this homogeneous approach is compared with an approach that is based on four flood types with different spatial discharge patterns. For each type, a regression model was created and used in a Monte-Carlo framework to derive heterogeneous scenarios. Per scenario, four cumulative impact indicators were calculated: (1) the total inundated area, (2) the exposed settlement and industrial areas, (3) the exposed population and 4) the potential building loss. Their frequency curves were used to establish a ranking of eight past flood events according to their severity. The investigation revealed that the two assumptions of the homogeneous approach do not hold. It tends to overestimate event probabilities in large areas. Therefore, the generation of heterogeneous scenarios should receive more attention. KW - damage estimation KW - discharge pattern KW - exposure KW - flood risk analysis KW - frequency analysis KW - land-use KW - population density Y1 - 2015 U6 - https://doi.org/10.1111/jfr3.12091 SN - 1753-318X VL - 8 IS - 3 SP - 247 EP - 262 PB - Wiley-Blackwell CY - Hoboken ER -