scholarly journals The effects of human movements on urban climate over Eastern China

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Lingyun Wu ◽  
Jingyong Zhang
Keyword(s):  
Human Mobility ◽  
Eastern China ◽  
Urban Climate ◽  
Intensity Variation ◽  
Large Cities ◽  
Complex Interactions ◽  
Spring Festival ◽  
Human Movements ◽  
Background Period ◽  
Cooling Effects

AbstractWe live on an urban planet with unprecedented human mobility. In this study, we collectively analyze ten large cities over densely populated Eastern China, and detect that mass people outflows during Spring Festival (SF) holiday significantly cool down urban climate expressed as urban heat island intensity variation particularly at the nighttime after minimizing the effects of other factors. We estimate that the average nighttime cooling effects of the ten large cities over Eastern China during the SF holiday relative to the nearby background period are 0.63 °C stronger during the 2000s than during the 1990s. The attribution analysis points to that the urban cooling effects are primarily caused by mass people outflows during the SF holiday. Our findings help to better understand the complex interactions of human population dynamics, urban development, and the environment, and may have important implications for promoting sustainable, people-centered, and resilient development of our urban planet.

scholarly journals Tracking the global reduction of marine traffic during the COVID-19 pandemic

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
David March ◽  
Kristian Metcalfe ◽  
Joaquin Tintoré ◽  
Brendan J. Godley
Keyword(s):  
Large Scale ◽  
Human Mobility ◽  
Western Mediterranean ◽  
Western Mediterranean Sea ◽  
Marine Traffic ◽  
Human Movements ◽  
Exclusive Economic Zones ◽  
Global Impacts ◽  
Economic Zones

AbstractThe COVID-19 pandemic has resulted in unparalleled global impacts on human mobility. In the ocean, ship-based activities are thought to have been impacted due to severe restrictions on human movements and changes in consumption. Here, we quantify and map global change in marine traffic during the first half of 2020. There were decreases in 70.2% of Exclusive Economic Zones but changes varied spatially and temporally in alignment with confinement measures. Global declines peaked in April, with a reduction in traffic occupancy of 1.4% and decreases found across 54.8% of the sampling units. Passenger vessels presented more marked and longer lasting decreases. A regional assessment in the Western Mediterranean Sea gave further insights regarding the pace of recovery and long-term changes. Our approach provides guidance for large-scale monitoring of the progress and potential effects of COVID-19 on vessel traffic that may subsequently influence the blue economy and ocean health.

Statistical modeling of fire brigade operations with respect to extreme precipitation events over Berlin

2021 ◽  
Author(s):  
Alexander Pasternack ◽  
Ines Langer ◽  
Henning W. Rust ◽  
Uwe Ulbrich
Keyword(s):  
Urban Climate ◽  
Heavy Precipitation ◽  
Radar Data ◽  
Climate Conditions ◽  
Large Cities ◽  
Fire Brigade ◽  
Extreme Precipitation Events ◽  
Highly Sensitive ◽  
Part Modeling ◽  
Precipitation Events

<p>Large cities and urban regions are highly sensitive to impacts caused by extreme events (e.g. heavy rainfall). As problems caused by hazardous atmospheric events are expected to intensify due to the Anthropogenic Climate Change, adequate adaptation planning of urban infrastructure is needed. Planning adaptations not only requires further research on potential impacts under changing climate conditions as a basis, but also a check of the practical feasibility for stakeholders.</p><p>Under the BMBF research program “Urban Climate Under Change” ([UC]²), we relate heavy precipitation events over Berlin to the respective fire brigade operations. Here, the precipitation data are based on temporally high resolved radar data. The fire brigade operation data are available on time and location, but the number of recorded events is small, and their distribution is highly overdispersive compared to a Poisson model. To account for this problem we apply a two part hurdle model with one part modeling the probability of the occurrence of fire brigade operations and one part modeling the actual number of operations given that at least one operation occurs. In the corresponding statistical models the parameters of the distributions are described by additive predictors, which are based on precipitation duration and intensity as well as building density. Based on 10 years of data with a cross validation setup, both the occurrence model and the model for the number of operations significantly outperform the reference climatology for certain areas over Berlin.</p>

scholarly journals Research on Collective Human Mobility in Shanghai Based on Cell Phone Data

2020 ◽  
Vol 9 (1) ◽  
pp. 44-62
Author(s):  
Xiyuan Ren ◽  
De Wang
Keyword(s):  
Temporal Variation ◽  
High Frequency ◽  
Cell Phone ◽  
Large Scale ◽  
Human Mobility ◽  
Indicator System ◽  
Data Sources ◽  
Census Tracts ◽  
Aggregate Distribution ◽  
Human Movements

The high-frequency mobility of a massive population has caused an enormous influence on the urban internal structure, which is unable to be described by traditional data sources. While recent advances in location-based technologies provides new opportunities for researchers to understand daily human movements and the structure as a whole. The article aims to explore human spatial movements and their aggregate distribution in Shanghai using large-scale cell phone data. The trajectory of each individual is extracted from cell phone data after data cleansing. Then, an indicator system which includes mobility intensity, mobility stability, influential range, and temporal variation is developed to describe collective human mobility features in census tracts scale. Finally, spatial elements are extracted using the indicator system and the structure of human mobility in Shanghai is discussed.

From Online BL Fandom to the CCTV Spring Festival Gala

2018 ◽  
Author(s):  
Shuyan Zhou
Keyword(s):  
Social Implications ◽  
Internet Culture ◽  
Complex Interactions ◽  
Spring Festival ◽  
Media Discourses ◽  
Different Cultures ◽  
A Performance

Regarding the question of politics and play in Chinese Internet culture, this chapter re-examines particular effects of netizens’ carnival practices, as well as the complex interactions and contradictions among cyberculture, the official culture, and consumerism in China, by centering on a specific case of “Looking for Leehom” (zhao Lihong) and its related media discourses in 2012 and 2013. The case serves as an influential online carnival, starting from an online Boy’s Love fandom of those who participated in the fantasy matchmaking of two male celebrities. Further, it raises large questions about resistance, complicity, and negotiation among different cultures and media, particularly considering that online carnival was appropriated by a performance on the CCTV Spring Festival Gala in 2013 and then commented on by newspapers and magazines. The chapter inspects how the pleasure of Boy’s Love fantasy has been transferred, censored, and re-enabled between cyberculture and offline societies. By rethinking Bakhtin’s interpretation of carnival, the chapter concludes by exploring the cultural and social implications of “Looking for Leehom” and the potential power of the netizens’ fantasy.

Urban Climate and Risk

2017 ◽  
Author(s):  
Teodoro Georgiadis
Keyword(s):  
Large Scale ◽  
Heat Waves ◽  
Urban Climate ◽  
Urban Heat Islands ◽  
Urban Metabolism ◽  
Extreme Weather Events ◽  
Management Skills ◽  
Urban Centers ◽  
Heat Islands ◽  
Complex Interactions

This work reports on the main physical processes that arise in the environment of the megacity from the “urban metabolism”—the complex interactions of the climate with the activities performed in the city and its built structure and texture—as well as on associated large-scale processes that generate hazards for the megacity’s inhabitants. It is estimated that in a few decades most of the world’s population will live in urban centers. Both the growth of megacities and climate change will increase the vulnerability of huge sectors of the population to climatic consequences of the urban metabolism. These include urban heat islands, pollution, and extreme weather events such as heat waves and floods. Developing policies to mitigate these threats will require integrating scientific knowledge with management skills, communication among cities about effective approaches, and taking into account residents’ needs for health and the capacity to live safely.

scholarly journals SRMM: A Social Relationship-Aware Human Mobility Model

Electronics ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 221 ◽  
Author(s):  
Dat Van Anh Duong ◽  
Seokhoon Yoon
Keyword(s):  
Social Context ◽  
Social Relationships ◽  
Social Relationship ◽  
Human Mobility ◽  
Real Life ◽  
Human Movement ◽  
Mobility Model ◽  
Power Law Distribution ◽  
Road Map ◽  
Human Movements

Since human movement patterns are important for validating the performance of wireless networks, several traces of human movements in real life have been collected. However, collecting data about human movements is costly and time-consuming. Moreover, multiple traces are demanded to test various network scenarios. As a result, a lot of synthetic models of human movement have been proposed. Nevertheless, most of the proposed models were often based on random generation, and cannot produce realistic human movements. Although there have been a few models that tried to capture the characteristics of human movement in real life (e.g., flights, inter-contact times, and pause times following the truncated power-law distribution), those models still cannot reflect realistic human movements due to a lack of consideration for social context among people. To address those limitations, in this paper, we propose a novel human mobility model called the social relationship–aware human mobility model (SRMM), which considers social context as well as the characteristics of human movement. SRMM partitions people into social groups by exploiting information from a social graph. Then, the movements of people are determined by considering the distances to places and social relationships. The proposed model is first evaluated by using a synthetic map, and then a real road map is considered. The results of SRMM are compared with a real trace and other synthetic mobility models. The obtained results indicate that SRMM is consistently better at reflecting both human movement characteristics and social relationships.

scholarly journals Comparative Study on the Cooling Effects of Green Space Patterns in Waterfront Build-Up Blocks: An Experience from Shanghai

2020 ◽  
Vol 17 (22) ◽  
pp. 8684
Author(s):  
Yunfang Jiang ◽  
Shidan Jiang ◽  
Tiemao Shi
Keyword(s):  
Green Space ◽  
Urban Climate ◽  
Regression Tree ◽  
Cooling Effect ◽  
Distribution Data ◽  
View Factor ◽  
Marginal Effect ◽  
Adaptive Planning ◽  
Boosted Regression Tree ◽  
Cooling Effects

Different structural patterns of waterfront green space networks in built-up areas have different synergistic cooling characteristics in cities. This study’s aim is to determine what kinds of spatial structures and morphologies of waterfront green spaces offer a good cooling effect, combined with three different typical patterns in Shanghai. A multidimensional spatial influence variable system based on the cooling effect was constructed to describe the spatial structural and morphological factors of the green space network. The ENVI-met 4.3 software, developed by Michael Bruse at Bochum, German, was used to simulate the microclimate distribution data, combined with the boosted regression tree (BRT) model and the correlation analysis method. The results showed that at the network level, the distance from the water body and the connectivity of green space had a stronger cooling correlation. The orientation of green corridors consistent with a summer monsoon had larger cooling effect ranges. In terms of spatial morphology, the vegetation sky view factor (SVF) and Vegetation Surface Albedo (VSAlbedo) had an important correlation with air temperature (T), and the green corridor with a 20–25 m width had the largest marginal effect on cooling. These results will provide useful guidance for urban climate adaptive planning and design.

scholarly journals Spatial Assessment of Urban Climate Change Vulnerability during Different Urbanization Phases

2019 ◽  
Vol 11 (8) ◽  
pp. 2406 ◽  
Author(s):  
Cheng He ◽  
Liguo Zhou ◽  
Weichun Ma ◽  
Yuan Wang
Keyword(s):  
Climate Change ◽  
Urban Areas ◽  
Anthropogenic Activities ◽  
Urban Climate ◽  
Rapid Urbanization ◽  
Climate Change Vulnerability ◽  
Complex Interactions ◽  
Societal Changes ◽  
Vulnerability Framework ◽  
The Relationship

In urban areas, concentrated populations and societal changes intensify the influence of climate change. However, few studies have focused on vulnerability to climate-related risks on the scale of a single urban area. Against this backdrop, we reconstructed a spatial vulnerability framework based on the drivers-pressures-state-impact-response (DPSIR) model to reflect the complex interactions between urbanization and climate change and to integrate the natural and socio-economic factors of urban areas into this framework. Furthermore, to explore the relationship between rapid urbanization and climate change, we studied data from two years that represented different stages of urbanization. The results showed that the index framework was able to reconcile these two concepts to reflect the complex interactions between urbanization and climate change. The assessment results indicate that the overall degree of climate change vulnerability exhibits a generally increasing and dispersing trend after rapid urbanization. The increasing trend is influenced by an increase in low-vulnerability areas, and the dispersing trend is influenced by anthropogenic activities caused by rapid urbanization. The changes are reflected in the following observations: 1. The suburbs are affected by their own natural environmental characteristics and rapid urbanization; the vulnerability level has risen in most areas but has declined in certain inland areas. 2. High-vulnerability regions show minor changes during this stage due to the lasting impact of climate change. Finally, the main environmental problems faced by high-vulnerability areas are discussed based on existing research.

scholarly journals Exploring the Roles of Local Mobility Patterns, Socioeconomic Conditions, and Lockdown Policies in Shaping the Patterns of COVID-19 Spread

2021 ◽  
Vol 13 (5) ◽  
pp. 112
Author(s):  
Mauricio Herrera ◽  
Alex Godoy-Faúndez
Keyword(s):  
Latin American ◽  
Low Income ◽  
Large Scale ◽  
Human Mobility ◽  
Epidemiological Data ◽  
High Income ◽  
Metropolitan Region ◽  
Mobility Patterns ◽  
Large Cities

The COVID-19 crisis has shown that we can only prevent the risk of mass contagion through timely, large-scale, coordinated, and decisive actions. This pandemic has also highlighted the critical importance of generating rigorous evidence for decision-making, and actionable insights from data, considering further the intricate web of causes and drivers behind observed patterns of contagion diffusion. Using mobility, socioeconomic, and epidemiological data recorded throughout the pandemic development in the Santiago Metropolitan Region, we seek to understand the observed patterns of contagion. We characterize human mobility patterns during the pandemic through different mobility indices and correlate such patterns with the observed contagion diffusion, providing data-driven models for insights, analysis, and inferences. Through these models, we examine some effects of the late application of mobility restrictions in high-income urban regions that were affected by high contagion rates at the beginning of the pandemic. Using augmented synthesis control methods, we study the consequences of the early lifting of mobility restrictions in low-income sectors connected by public transport to high-risk and high-income communes. The Santiago Metropolitan Region is one of the largest Latin American metropolises with features that are common to large cities. Therefore, it can be used as a relevant case study to unravel complex patterns of the spread of COVID-19.

scholarly journals Emergence of Urban Growth Patterns from Human Movements

2020 ◽  
Author(s):  
Fengli Xu ◽  
Yong Li ◽  
Chaoming Song
Keyword(s):  
Urban Growth ◽  
Large Scale ◽  
Scaling Laws ◽  
Human Mobility ◽  
Human Movement ◽  
Urban Morphology ◽  
Growth Patterns ◽  
Spatial Correlations ◽  
Movement Model ◽  
Human Movements

Abstract Cities grow in a bottom-up manner, leading to fractal-like urban morphology characterized by scaling laws. Correlated percolation has succeeded in modeling urban geometries by imposing strong spatial correlations. However, the origin of such correlations remains largely unknown. Very recently, our understanding of human movements has been revolutionized thanks to the increasing availability of large-scale human mobility data. This paper proposes a novel human movement model that offers a micro-foundation for the dynamics of urban growth. We compare the proposed model with three empirical datasets, which evidences that strong social couplings and long-memory effects are two fundamental principles responsible for the mystical spatial correlations. The model accounts for the empirically observed scaling laws, but also allows us to understand the city evolution dynamically.

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