Air pollution and emigration behaviors – evidence of Hanoi

Expeditious increase in population and industrialization has led to alarming rates of air pollution in all countries. However, developing economies have had to face a more adverse and severe impact. This had led to many changes in the day to day living of citizens. In this paper we have focused on the psychological process and predictors of migration intention of the people living in Hanoi, Vietnam. Two stratified random datasets of 475 people were used, and Bayesian analysis was performed on this dataset. We found out that the intent to move was negatively associated to the individual’s satisfaction with air quality. We also found that people who have family members that have fallen victim to a disease caused by air pollution are more likely to migrate. This paper discusses an important topic: immigration of the younger demographic, i.e. the Hanoi workforce, which may cause restrictions and hurdles in the city's urbanisation and development. The findings suggest that, if measures against air pollution are not taken, economic forces may be disrupted, posing a threat to urban growth. As a result, collaborative activities and steps need to be taken by the government to curb this unfortunate consequence.

Urban Form Dynamics and Modelling towards Sustainable Hinterland Development in North Cianjur, Jakarta–Bandung Mega-Urban Region

The urban form is the physical configuration of a city, developed over time and space. Urban form can be considered at different scales, from region to neighborhood, each carrying a different focus. North Cianjur serves as the hinterland and one of the conurbation corridors of the Jakarta–Bandung Mega-Urban Region, meaning that the balance between its function as an environmental buffer area and the destination of urban growth needs to be planned carefully. This paper explores the dynamics in North Cianjur and employs several model scenarios as a planning intervention using landscape dynamic tools and land-change modeling, with three scenarios employed: Business as Usual (BAU), Spatial Planning Policy (SPP), and Urban Containment (UCT). The result show that North Cianjur has transformed into a polycentric region with two urban zones, a peri-urban zone, and a rural zone in the northernmost part of the region. Urban form trends show a sprawling built-up pattern outside urban zones, and a compacted trend in urban zones due to expansion from the Jakarta and Bandung Metropolitan Area. UCT models appear to be the most optimal for implementation in North Cianjur, representing a way to accommodate urban growth and expansion inside the urban center while still maintaining regional sustainability.

Modelling and simulating ‘informal urbanization’: An integrated agent-based and cellular automata model of urban residential growth in Ghana

The global urban population is expected to grow by 2.5 billion over the next three decades, and 90% of this growth will occur in African and Asian countries. Urban expansion in these regions is often characterised by ‘informal urbanization’ whereby households self-build without planning permission in contexts of ambiguous, insecure or disputed property rights. Despite the scale of informal urbanization, it has received little attention from scholars working in the domains of urban analytics and city science. Towards addressing this gap, we introduce TI-City, an urban growth model designed to predict the locations, legal status and socio-economic status of future residential developments in an African city. In a bottom-up approach, we use agent-based and cellular automata modelling techniques to predict the geospatial behaviour of key urban development actors, including households, real estate developers and government. We apply the model to the city-region of Accra, Ghana, drawing on local data collection, including a household survey, to parameterise the model. Using a multi-spatial-scale validation technique, we compare TI-City’s ability to simulate historically observed built-up patterns with SLEUTH, a highly popular urban growth model. Results show that TI-City outperforms SLEUTH at each scale, suggesting the model could offer a valuable decision support tool in similar city contexts.

Mesure de la vulnérabilité des milieux urbains au Cameroun face au changement climatique

Les différentes catastrophes survenues en milieu urbain au Cameroun récemment, mettent en exergue les désormais dangers permanents qui pèsent sur les habitants. On note une augmentation des extrêmes : de hautes températures, des perturbations des régimes pluvieux et la récurrence des vents violents. Certains de ces effets sont amplifiés par la géographie contraignante de plusieurs villes et par l’influence anthropique sur l’environnement. En effet, d’une part les sites de plusieurs villes camerounaises ont soit des reliefs accidentés qui favorisent l’érosion des terrains, soit des configurations planes qui limitent l’évacuation gravitaire de l’eau de ruissellement. D’autre part, la croissance urbaine rapide et la prolifération des bidonvilles qui couvrent près de 65 à 70% de la superficie urbaine, usent plus rapidement les ouvrages et infrastructures d’assainissement urbaines lorsqu’ils existent dus à l’imperméabilisation accélérée et continue du sol urbain ainsi qu’à la mauvaise gestion des déchets. L’urgence de trouver des solutions durables à ce phénomène est désormais sans équivoque. Elle nécessite un encadrement normatif inclusif plus performant que celui actuellement en vigueur, qui amène le pays vers la résilience. The disasters that’ve occurred recently in urban areas in Cameroon, highlight the permanent dangers weighing on the inhabitants. There is an increase in extremes climate parameters: high temperatures, rainfall disturbances and the recurrence of gales. Some of these effects are amplified by both the constraining relief of several cities and human influence on the environment. In fact, on the one hand, the sites of several Cameroonian cities either have rugged reliefs that promote land erosion, or flat configurations that limit the gravity discharge of runoff water. On the other hand, the rapid urban growth and the proliferation of slums which cover nearly 65 to 70% of the urban area, wear out more quickly the works and urban sanitation infrastructures when they exist due to the accelerated and continuous waterproofing soil in addition to the poor waste management. The urgency to find lasting solutions to this phenomenon is now unequivocal. It requires an inclusive normative framework that is more effective than that currently in force, which brings the country towards resilience.

Air pollution and emigration behaviors – evidence of Hanoi

Expeditious increase in population and industrialization has led to alarming rates of air pollution in all countries. However, developing economies have had to face a more adverse and severe impact. This had led to many changes in the day to day living of citizens. In this paper we have focused on the psychological process and predictors of migration intention of the people living in Hanoi, Vietnam. Two stratified random datasets of 475 people were used, and Bayesian analysis was performed on this dataset. We found out that the intent to move was negatively associated to the individual’s satisfaction with air quality. We also found that people who have family members that have fallen victim to a disease caused by air pollution are more likely to migrate. This paper discusses an important topic: immigration of the younger demographic, i.e. the Hanoi workforce, which may cause restrictions and hurdles in the city's urbanisation and development. The findings suggest that, if measures against air pollution are not taken, economic forces may be disrupted, posing a threat to urban growth. As a result, collaborative activities and steps need to be taken by the government to curb this unfortunate consequence.

Public Transit Development Predicts Spatial Distribution of Dengue Virus Incidence in Medellín, Colombia

Dengue is a growing global threat in some of the world’s most rapidly growing landscapes. Urbanization and human movement affect the spatial dynamics and magnitude of dengue outbreaks; however, precise effects of urban growth on dengue is not well understood because of a lack of sufficiently fine-scaled data. We analyzed nine years of address-level dengue case data in Medellin, Colombia during a period of public transit expansion. We correlate changes in the spread and magnitude of localized outbreaks to changes in accessibility and usage of public transit. Locations closer to and with a greater utilization of public transit had greater dengue incidence. This relationship was modulated by socioeconomic status; lower socioeconomic status locations experienced stronger effects of public transit accessibility and usage on dengue incidence. Public transit is a vital urban resource, particularly among low socioeconomic populations; these results highlight the importance of public health services concurrent with urban growth.