Man-made disaster on urban area: subsidence and underground salt dissolution in Maceio (Brazil) revealed by remote sensing and numerical modelling

2021 ◽  
Author(s):  
Magdalena Vassileva ◽  
Djamil Al-Halbouni ◽  
Mahdi Motagh ◽  
Thomas R. Walter ◽  
Torsten Dahm ◽  
...  
Keyword(s):  
Urban Areas ◽  
Material Removal ◽  
Distinct Element ◽  
Surface Displacement ◽  
Synthetic Aperture ◽  
Water Percolation ◽  
The World ◽  
Formation Of Cracks ◽  
Salt Mining ◽  
Precipitation Events

<p>Land subsidence hazard affects many highly populated urban areas of the world as a consequence of natural and/or anthropogenic derived geomechanical rock alterations. Here we exploit the full archive of Synthetic Aperture Radar (SAR data) and present a 16-years history (2004-2020) of surface displacement affecting the federal capital of Maceió (Alagoas, Brazil), where sinkhole formation and fractures on infrastructures have been intensified since early 2018, forcing authorities to relocate the affected residence and pose the building under demolition. The geodetic result shows that precursory deformations were already visible in early 2000’s, reaching in November 2020 a maximum cumulative subsidence of approximately 2 m near the Mundaú lagoon coast. The maximum rate of subsidence is estimated at 27 cm/year. Numerical elastic source modelling proves that the subsidence is associated with localized, deep seated material removal at the location and depth where salt mining is performed. More sophisticated 2D distinct element method highlights the formation of cracks in sedimentary layers that eventually enables strong water percolation from rather superficial aquifers into the deeper underground, with potential increase of material dissolution and erosion. We discuss the accelerating subsidence rates, the influence of severe precipitation events to the aforementioned geological instability and the related dynamic evolution of the subsidence hazard by generating dynamic geohazard maps valuable for further infrastructure risk assessment.</p>

scholarly journals A decade-long silent ground subsidence hazard culminating in a metropolitan disaster in Maceió, Brazil

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Magdalena Vassileva ◽  
Djamil Al-Halbouni ◽  
Mahdi Motagh ◽  
Thomas R. Walter ◽  
Torsten Dahm ◽  
...  
Keyword(s):  
Urban Areas ◽  
Ground Deformation ◽  
Anthropogenic Activities ◽  
Surface Displacement ◽  
Ground Subsidence ◽  
Anthropogenic Processes ◽  
Precipitation Events

AbstractGround subsidence caused by natural or anthropogenic processes affects major urban areas worldwide. Sinkhole formation and infrastructure fractures have intensified in the federal capital of Maceió (Alagoas, Brazil) since early 2018, forcing authorities to relocate affected residents and place buildings under demolition. In this study, we present a 16-year history (2004–2020) of surface displacement, which shows precursory deformations in 2004–2005, reaching a maximum cumulative subsidence of approximately 200 cm near the Mundaú Lagoon coast in November 2020. By integrating the displacement observations with numerical source modelling, we suggest that extensive subsidence can be primarily associated with the removal of localized, deep-seated material at the location and depth where salt is mined. We discuss the accelerating subsidence rates, influence of severe precipitation events on the aforementioned geological instability, and related hazards. This study suggests that feedback destabilization mechanisms may arise in evaporite systems due to anthropogenic activities, fostering enhanced and complex superficial ground deformation.

Urban Transport

2018 ◽  
Author(s):  
José van
Keyword(s):  
Urban Areas ◽  
Urban Transport ◽  
Transport Sector ◽  
Public And Private ◽  
Transport Services ◽  
Ride Sharing ◽  
The World ◽  
Private And Public ◽  
Selection Mechanisms

Platformization affects the entire urban transport sector, effectively blurring the division between private and public transport modalities; existing public–private arrangements have started to shift as a result. This chapter analyzes and discusses the emergence of a platform ecology for urban transport, focusing on two central public values: the quality of urban transport and the organization of labor and workers’ rights. Using the prism of platform mechanisms, it analyzes how the sector of urban transport is changing societal organization in various urban areas across the world. Datafication has allowed numerous new actors to offer their bike-, car-, or ride-sharing services online; selection mechanisms help match old and new complementors with passengers. Similarly, new connective platforms are emerging, most prominently transport network companies such as Uber and Lyft that offer public and private transport options, as well as new platforms offering integrated transport services, often referred to as “mobility as a service.”

scholarly journals High Diversity in Urban Areas: How Comprehensive Sampling Reveals High Ant Species Richness within One of the Most Urbanized Regions of the World

Diversity ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 358
Author(s):  
François Brassard ◽  
Chi-Man Leong ◽  
Hoi-Hou Chan ◽  
Benoit Guénard
Keyword(s):  
Exotic Species ◽  
Urban Areas ◽  
Urban Landscapes ◽  
Dual Roles ◽  
Ant Communities ◽  
Continuous Increase ◽  
Tropical Regions ◽  
The World ◽  
Ant Diversity ◽  
The Vertical Distribution

The continuous increase in urbanization has been perceived as a major threat for biodiversity, particularly within tropical regions. Urban areas, however, may still provide opportunities for conservation. In this study focused on Macao (China), one of the most densely populated regions on Earth, we used a comprehensive approach, targeting all the vertical strata inhabited by ants, to document the diversity of both native and exotic species, and to produce an updated checklist. We then compared these results with 112 studies on urban ants to illustrate the dual roles of cities in sustaining ant diversity and supporting the spread of exotic species. Our study provides the first assessment on the vertical distribution of urban ant communities, allowing the detection of 55 new records in Macao, for a total of 155 ant species (11.5% being exotic); one of the highest species counts reported for a city globally. Overall, our results contrast with the dominant paradigm that urban landscapes have limited conservation value but supports the hypothesis that cities act as gateways for exotic species. Ultimately, we argue for a more comprehensive understanding of ants within cities around the world to understand native and exotic patterns of diversity.

scholarly journals Development of a Radar Reflector Kit for Older Adults to Use to Signal Their Location and Needs in a Large-Scale Earthquake Disaster

2021 ◽  
Vol 13 (10) ◽  
pp. 1883
Author(s):  
Yuma Morisaki ◽  
Makoto Fujiu ◽  
Ryoichi Furuta ◽  
Junichi Takayama
Keyword(s):  
Older Adults ◽  
Synthetic Aperture Radar ◽  
Satellite Imagery ◽  
Disaster Response ◽  
Large Scale ◽  
Synthetic Aperture ◽  
Earthquake Disaster ◽  
Large Numbers ◽  
The World ◽  
Vulnerable People

In Japan, older adults account for the highest proportion of the population of any country in the world. When large-scale earthquake disasters strike, large numbers of casualties are known to particularly occur among seniors. Many are physically or mentally vulnerable and require assistance during the different phases of disaster response, including rescue, evacuation, and living in an evacuation center. However, the growing number of older adults has made it difficult, after a disaster, to quickly gather information on their locations and assess their needs. The authors are developing a proposal to enable vulnerable people to signal their location and needs in the aftermath of a disaster to response teams by deploying radar reflectors that can be detected in synthetic aperture radar (SAR) satellite imagery. The purpose of this study was to develop a radar reflector kit that seniors could easily assemble in order to make this proposal feasible in practice. Three versions of the reflector were tested for detectability, and a sample of older adults was asked to assemble the kits and provide feedback regarding problems they encountered and regarding their interest in using the reflectors in the event of a large-scale disaster.

Analysing urban floods and combined sewer overflows in a changing climate

2011 ◽  
Vol 2 (4) ◽  
pp. 260-271 ◽  
Author(s):  
V. Nilsen ◽  
J. A. Lier ◽  
J. T. Bjerkholt ◽  
O. G. Lindholm
Keyword(s):  
Climate Change ◽  
Time Series ◽  
Urban Areas ◽  
Convective Precipitation ◽  
Urban Drainage ◽  
Combined Sewer Overflows ◽  
Extreme Precipitation Events ◽  
Combined Sewer ◽  
Sewer Overflows ◽  
Precipitation Events

Climate change is expected to lead to an increased frequency and intensity of extreme precipitation events. For urban drainage, the primary adverse effects are more frequent and severe sewer overloading and flooding in urban areas, and higher discharges through combined sewer overflows (CSO). For assessing the possible effects of climate change, urban drainage models are run with climate-change-adjusted input data. However, current climate models are run on a spatial–temporal scale that is too coarse to resolve processes relevant to urban drainage modelling, in particular convective precipitation events. In the work reported here the delta-change method was used to develop a high-resolution time series of precipitation for the period 2071–2100 based on a recently produced climate model precipitation time series for Oslo. The present and future performance of the sewer networks was determined using MOUSE software. The simulations indicated future increases in annual CSO discharge of 33% when comparing years of maximum annual runoff. There is also an 83% increase in annual CSO discharge when comparing years of maximum annual precipitation. In addition, there are increases in the flooding of manholes and increased levels of backwater in pipes, which translates into more flooding of basements.

Beyond studentification in United States College Towns: Neighborhood change in the knowledge nodes, 1980–2010

2017 ◽  
Vol 49 (6) ◽  
pp. 1341-1360 ◽  
Author(s):  
Nathan S Foote
Keyword(s):  
United States ◽  
Middle Class ◽  
Knowledge Economy ◽  
Urban Areas ◽  
Global Economy ◽  
Neighborhood Change ◽  
Global Knowledge ◽  
College Towns ◽  
The World ◽  
Social Geographies

With the rise of the cognitive-cultural (or knowledge) economy, urban areas around the world have experienced significant changes in their social geographies. Studentification is one such change that has occurred in cities hosting major universities around the world. This study extends the analysis of social change to vital knowledge nodes in the networked global economy: United States college towns. K-means cluster analysis is used to identify neighborhood types in ten cities with major research universities across four Census years: 1980, 1990, 2000, and 2010. Temporal and spatial analyses are then conducted to determine how these knowledge nodes have changed with the decline of the industrial economy and the rise of the knowledge economy. The analysis indicates the presence of six neighborhood types in these college towns: Middle Class, Minority-Concentrated, Stability, Elite, Mix/Renter, and Student. Over the course of the study period, the number of Elite neighborhoods increased considerably, while the number of Middle Class neighborhoods plummeted. The number of Mix/Renter neighborhoods also increased. Spatially, Student and Minority-Concentrated neighborhoods generally remained fairly clustered in the same areas across the study period. Elite neighborhoods spread across wider geographical areas over the course of the study period. These results are compared to previous studies on neighborhood change. The comparisons reveal that the knowledge nodes show some similar patterns to studentifying cities and to rapidly growing nodes in areas with ties to the global knowledge economy.

Reconceptualizing the Public Spaces of New Urban Areas in Hanoi: The End or the New of Public-Making?

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Minh-Tung Tran ◽  
◽  
Tien-Hau Phan ◽  
Ngoc-Huyen Chu ◽  
◽  
...  
Keyword(s):  
Public Space ◽  
Urban Areas ◽  
Public Spaces ◽  
The Public ◽  
Doi Moi ◽  
The World ◽  
Relationship Of ◽  
The Relationship ◽  
The City ◽  
Neighborhood Level

Public spaces are designed and managed in many different ways. In Hanoi, after the Doi moi policy in 1986, the transfer of the public spaces creation at the neighborhood-level to the private sector has prospered na-ture of public and added a large amount of public space for the city, directly impacting on citizen's daily life, creating a new trend, new concept of public spaces. This article looks forward to understanding the public spaces-making and operating in KDTMs (Khu Do Thi Moi - new urban areas) in Hanoi to answer the question of whether ‘socialization’/privatization of these public spaces will put an end to the urban public or the new means of public-making trend. Based on the comparison and literature review of studies in the world on public spaces privatization with domestic studies to see the differences in the Vietnamese context leading to differences in definitions and roles and the concept of public spaces in KDTMs of Hanoi. Through adducing and analyzing practical cases, the article also mentions the trends, the issues, the ways and the technologies of public-making and public-spaces-making in KDTMs of Hanoi. Win/loss and the relationship of the three most important influential actors in this process (municipality, KDTM owners, inhabitants/citizens) is also considered to reconceptualize the public spaces of KDTMs in Hanoi.

Cancer: A Life Threatening Peril Becoming Lifestyle Disease

2021 ◽  
pp. 03
Author(s):  
Sara Hayee ◽  
Amna Rehman
Keyword(s):  
Cancer Patients ◽  
Urban Areas ◽  
Past History ◽  
The World ◽  
Cause Of Deaths ◽  
Life Threatening ◽  
Abnormal Cells ◽  
Lifestyle Disease ◽  
First Time ◽  
Day By Day

Caner a dreadful disease is actually one large group of diseases which dates back to times of “Hippocrates”, The Father of Medicine, (460-370BC) who used this name for the first time to talk about non-ulcer and ulcer forming tumors. Theevidence of its presence from the very past history comes from fossilized “Egyptian Mummies” having tumors on bones. Then Galen (130-200 AD) used the term “Oncos” to explain tumors. So it's a disease involving growth of abnormal cells, their proliferation and metastasizing the other tissues and organs. Now we know that biology has a branch namedOncology to deal with the scientific study of cancer and oncogenes. It took centuries to get knowledge and use modern technologies against this malady. Now we know cancer is a group disease which has hundreds of types. 19th Century saw much advancement towards its cure. Along with surgery, radiotherapy and chemotherapy were the main methods to cure cancer patients. Day by day, scientists are looking for new methods to control and cure of this curse. Hundreds of natural medicinal compounds are being tested to use clinically for its cure in order to replace the radiotherapy andchemotherapy and lower their side effects. But humanity is still fighting against this disease as the numbers of cases throughout the world are increasing day by day. If we look on the reports p r e s e n t e d b y W H O ( W o r l d H e a l t hOrganization), Cancer is the second leading cause of deaths globally which means one person in every six deaths, dies due to cancer. In 2018, the most common types of cancers reported in men were of liver, prostate, stomach, lung andcolorectal. Whereas in females the most common forms were breast, thyroid, cervical and colorectal. Cancer has become a global disasterfamily of the patient. It imparts physical, emotional and financial crisis. Unfortunately, the condition is bitterer in under developing countries. Cancer has become a lifestyle disease these days. We are living in the world withsuperficial comfort but we are breathing with urbanizations, ozone depletion, exposure to microwave and ultraviolet radiations, hazardous chemicals etc. Moreover, It is becoming a lifestyle disease due to lack of exercise, Obesity, consumptions of drugs, tobacco and alcohols. The cases of cancers are reported more in urban areas than in rural areasmore likely due to above mentioned factors. The ratio of cancer patients is expected to raise up-to 27.5 million by 2040 globally. So the battle is never ending, Humans need to figure out the factors and cutting these from their lives in orderto live a healthy life which is a blessing indeed. which is not only crunching the cancer patient but it also has damaging effects on the whole

Identifying land cover suitability factors for photovoltaic installations with focus on cropland and urban areas

2021 ◽  
Author(s):  
Madhura Yeligeti ◽  
Wenxuan Hu ◽  
Yvonne Scholz ◽  
Kai von Krbek
Keyword(s):  
Land Cover ◽  
Urban Areas ◽  
Energy Systems ◽  
Energy System ◽  
Climatic Conditions ◽  
System Modelling ◽  
Solar Photovoltaic ◽  
Land Cover Types ◽  
The World ◽  
Urban Settlements

<p>Solar photovoltaic (PV) systems will foreseeably be an integral part of future energy systems. Land cover area analysis has a large influence on estimatiin of long-term solar photovoltaic potential of the world in high spatial detail. In this regard, it is often seen in contemporary works, that the suitability of various land cover categories for PV installation is considered in a yes/no binary response. While some areas like natural parks, sanctuaries, forests are usually completely exempted from PV potential calculations, other land over categories like urban settlements, bare, sparsely vegetated areas, and even cropland can principally support PV installations to varying degrees. This depends on the specific land use competition, social, economic and climatic conditions, etc. In this study, we attempt to evaluate these ‘factors of suitability’ of different land cover types for PV installations.</p><p>As a basis, the openly available global land cover datasets from the Copernicus Land Monitoring Service were used to identify major land cover types like cropland, shrubland, bare, wetlands, urban settlements, forests, moss and snow etc. For open area PV installations, with a focus on cropland, we incorporated the promising technology of ‘Agri-voltaics’ in our investigation. Different crops have shown to respond positively or negatively, so far, to growing under PV panels according to various experimental and commercial sources. Hence, we considered 18 major crops of the world (covering 85% of world cropland) individually and consequently, evaluated a weighted overall suitability factor of cropland cover for PV, for three acceptance scenarios of future.</p><p>For rooftop PV installations in urban areas, various socio-economic and geographical influences come in play. The rooftop area available and further usable for PV depends on housing patterns (roof type, housing density) which vary with climate, population density and socio-economic lifestyle. We classified global urban areas into several clusters based on combinations of these factors. For each cluster, rooftop area suitability is evaluated at a representative location using the land cover maps, the Open Street Map and specific characteristics of the cluster.</p><p>Overall, we present an interdisciplinary approach to integrate technological, social and economic aspects in land cover analysis to estimate PV potentials. While the intricacies may still be insufficient for planning small localized energy systems, this can reasonably benefit energy system modelling from a regional to international scale.</p>

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