While moments of historic rupture do usher in radically new conditions for claiming urban space and power, the eras they cleave do not align neatly in the lives of the urban precariat. Rather, they ...overspill and interdigitate, saturating the present. This paper vivifies heterotemporality as an analytic, rather than descriptive, category for urban politics and scholarship. Drawing together Walter Benjamin's radical mode of historical and image‐centric inquiry with Mimi Nguyen's and Dai Jinhua's critiques of recombinant imperial formations, I seek to unsettle the uncritical chronopolitics of rupture that has practically and discursively undergirded dispossession in Phnom Penh, Cambodia. Arguing against strategic representations of urban rupture as only a break from the past, I offer instead a dialectical conception of rupture as interacting movements of break and amplification of the past in the present. Advancing ‘archiveology’ as an urban research praxis that activates a heterotemporal, collective urban archive – composed of the built landscape, oral accounts, historical records and filmic representations – shocks the potential of what has been, constellating alternative politics of the present. I suggest that this theoretical‐methodological framework offers critical insights beyond Phnom Penh, especially for other historic‐geographies that have been strategically attenuated via categorical post‐s (e.g., post‐colonial, post‐socialist, post‐conflict).
Short
Arguing against strategic representations of urban rupture as only a break from the past, this paper offers instead a dialectical conception of rupture as interacting movements of break and amplification of the past in the present. Methodologically, the paper advances ‘archiveology’ as an urban research praxis that actives a heterotemporal, collective urban archive in order to shock the potential of ‘what has been’, for an alternative politics of the present.
In the past decades, there has been a resurgence of public bike-sharing systems (BSSs). While it is claimed that social and environmental benefits are associated with the implementation of BSSs, few ...empirical studies have investigated the actual congestion reduction effect of BSSs on cities. To fill such gap, this paper aims to examine whether the launch of BSSs can reduce citywide congestion. With a panel dataset of 96 urban areas in the US from 2005 to 2014, we employed a difference-in-differences model with two-way fixed-effects panel regression. The results suggested that the introduction of BSSs shows a significant mixed impact on congestion in general: Larger cities get better off but richer cities get worse off. Such results are consistent with both subsample regression with propensity score matching and different congestion measures. Post-hoc analysis reveals that BSSs have a significant positive effect on reducing rush-hour congestion. Finally, implications, limitations, and future work directions are offered
•We examined the influence of bike-sharing system (BSSs) on congestion in 96 US urban areas across ten years (2005–2014).•We employed a difference-in-differences model with two-way fixed-effects panel regression.•The launch of BSSs has mixed effects on congestion in general.•By introducing BSSs, larger cities get better off while richer cities get worse off.•BSSs can reduce peak-hour congestion.
According to Dockry et al., informal relationships can be built by: a) writing a letter to the tribal government explaining a project proposal and asking for tribal input. b) holding an open public ...meeting and sending an invitation to tribal natural resource departments. c) attending a tribal community event like a feast, pow wow, or school science fair. 3.Scouse et al. found the benefit of combining American Community Survey Public Micro-data Samples with input-output analysis is to: a) better quantify the supply-chain relationships between industries. b) increase resolution at the household level of the social-accounting matrix. c) describe how individual earnings compare to household earnings. 7.According to Nowak and Greenfield, the states with the greatest amount of urban/community land are: a) Texas, California, Florida, Georgia, and Pennsylvania. b) New Jersey, Rhode Island, Massachusetts, Connecticut, and Maryland. c) Alaska, California, Texas, Florida, and Arizona. 9.
Urban areas are increasingly vulnerable to sudden flooding disasters caused by intense rainfall and high imperviousness degree, resulting in great economic losses and human casualties. Interactions ...between rainfall data and urban catchment characteristics highlight the urgent need of accurate and effective precipitation data to apply in reliable hydrological simulations. However, it remains a challenge to obtain accurate rainfall datasets on such small scales in urban areas. As satellite remote sensing is the only method that can achieve global observation, it is important to evaluate satellite precipitation products in their ability to accurately capture intense precipitation on urban flood scales. This study evaluates the performance of the latest version 06B (V06B) Integrated Multi-satellitE Retrievals for Global Precipitation Measurement (IMERG) in North China Plain, with using the Radar-Gauge merged precipitation estimates as reference data. First, it could be concluded that IMERG fails to accurately estimate precipitation in the whole study area, having the problem of overestimating light precipitation and underestimating heavy precipitation. Second, results show that IMERG has poor ability to capture heavy precipitation on small scales, with the percentage of Hit nearly 0 and the percentage of Miss higher than 40 % for all the precipitation cases. Third, with the expansion of heavy precipitation centers' coverage, the problem of IMERG not to detect heavy precipitation gets mitigated, with the percentage of Miss decreasing by 14 % (19 %). However, the ability to capture both spatial location and precipitation intensity is still not good, the percentage of Hit ranging from 0.05 % to 7 %, without obvious improvement. When IMERG is able to capture the center of strong precipitation, it also tends to overestimate the weak precipitation around the center of strong precipitation. Results of this study provide an improved understanding of how well the V06B IMERG products capture the heavy precipitation center at small scales in urban areas, which will be useful for both developers and users of IMERG.
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•IMERG can capture spatial distribution of precipitation on a large spatial scale•IMERG has poor ability to detect heavy precipitation at small scales•When the coverage of heavy precipitation expands, the performance of IMERG to capture heavy precipitation gets improved•IMERG tends to overestimate the weak precipitation around the center of strong precipitation
The article is devoted consideration of the processes of ecologization of urbanized territories. The author notes that urbanization has caused many environmental problems, among which the ...vulnerability of urban systems and the low level of environmental quality can be noted. In the modern Russian Federation, 75% of the total population of the country lives in urban areas. The features of the development of modern urbanized territories, leading to environmental pollution and further degradation, are highlighted. Improving the system of green spaces, based on urban zoning, soil conditions, climatic features, can significantly improve the ecological situation in the urban environment. It is noted that urban ecology leads to an increase in the quality of life of the population living in these territories through the greening of urban landscapes, approaching the natural environment, phytomelioration , and the formation of an attractive image of the city. Some physiological and ecological features of green spaces, which determine their important role in the greening of urban areas, have been studied. Plant species that are most suitable for landscaping urban areas in modern conditions are proposed. It is also noted that the growth of the ecological and economic competitiveness of the territory based on the use of an environmentally sound approach in the creation and operation of urban green spaces can cause an increase in revenues to the municipal budget.
Ground-level ozone (O3), fine particles (PM2.5), and nitrogen dioxide (NO2) are the most harmful urban air pollutants regarding human health effects. Here, we aimed at assessing trends in concurrent ...exposure of global urban population to O3, PM2.5, and NO2 between 2000 and 2019. PM2.5, NO2, and O3 mean concentrations and summertime mean of the daily maximum 8-h values (O3 MDA8) were analyzed (Mann-Kendall test) using data from a global reanalysis, covering 13,160 urban areas, and a ground-based monitoring network (Tropospheric Ozone Assessment Report), collating surface O3 observations at nearly 10,000 stations worldwide. At global scale, PM2.5 exposures declined slightly from 2000 to 2019 (on average, − 0.2 % year−1), with 65 % of cities showing rising levels. Improvements were observed in the Eastern US, Europe, Southeast China, and Japan, while the Middle East, sub-Saharan Africa, and South Asia experienced increases. The annual NO2 mean concentrations increased globally at 71 % of cities (on average, +0.4 % year−1), with improvements in North America and Europe, and increases in exposures in sub-Saharan Africa, Middle East, and South Asia regions, in line with socioeconomic development. Global exposure of urban population to O3 increased (on average, +0.8 % year−1 at 89 % of stations), due to lower O3 titration by NO. The summertime O3 MDA8 rose at 74 % of cities worldwide (on average, +0.6 % year−1), while a decline was observed in North America, Northern Europe, and Southeast China, due to the reduction in precursor emissions. The highest O3 MDA8 increases (>3 % year−1) occurred in Equatorial Africa, South Korea, and India. To reach air quality standards and mitigate outdoor air pollution effects, actions are urgently needed at all governance levels. More air quality monitors should be installed in cities, particularly in Africa, for improving risk and exposure assessments, concurrently with implementation of effective emission control policies that will consider regional socioeconomic imbalances.
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•We used 20-year of observationally constrained modelled data and ground-based observations covering 13,160 urban areas.•We estimated the city-level trends of urban population exposure to O3, PM2.5, and NO2.•Global PM2.5 exposure declined (− 0.2 % year−1) with 65 % of cities showing rising levels.•The annual NO2 mean concentrations increased at 71 % of cities (+ 0.4 % year−1).•Global exposure of urban population to O3 increased at 89 % of stations (+ 0.8 % year−1).
Abstract
Traditional understanding of urban income segregation is largely based on static coarse-grained residential patterns. However, these do not capture the income segregation experience implied ...by the rich social interactions that happen in places that may relate to individual choices, opportunities, and mobility behavior. Using a large-scale high-resolution mobility data set of 4.5 million mobile phone users and 1.1 million places in 11 large American cities, we show that income segregation experienced in places and by individuals can differ greatly even within close spatial proximity. To further understand these fine-grained income segregation patterns, we introduce a Schelling extension of a well-known mobility model, and show that experienced income segregation is associated with an individual’s tendency to explore new places (place exploration) as well as places with visitors from different income groups (social exploration). Interestingly, while the latter is more strongly associated with demographic characteristics, the former is more strongly associated with mobility behavioral variables. Our results suggest that mobility behavior plays an important role in experienced income segregation of individuals. To measure this form of income segregation, urban researchers should take into account mobility behavior and not only residential patterns.
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