scholarly journals Eolian chronology reveals causal links between tectonics, climate, and erg generation

Author(s):  
Shlomy Vainer ◽  
Ari Matmon ◽  
Yoav Ben Dor ◽  
Eric Verrecchia ◽  
Georges Aumaitre

Abstract The onset and intensification of eolian activity mark climatic transitions that promote wide-scale aridification, recorded by the generation and preservation of massive sand deposits. Evaluating the impact and implications of such repositories on Earth systems requires knowledge about the timing of their emplacement and the mechanisms responsible for their generation, which remain highly uncertain. Here we provide time constraints for the establishment of the Kalahari Erg, which is the largest continuous body of sand on Earth. We apply cosmogenic nuclide dating of sand from the Kalahari Desert combined with numerical modeling to determine when sand was introduced into the interior of southern Africa. Through the consideration of several scenarios, we show that major events of eolian sand transport and accumulation occurred between ~2.5 and 1 Myr ago. This substantial activity, which significantly altered environmental settings, corresponds to regional, continental, and global scale morphotectonic and climatic changes that contributed to the mass production and widespread dispersion of sand. These changes substantially altered existing habitats, thus constituting a crucial milestone for hominin evolution and migration throughout the African continent during the Pleistocene.

2015 ◽  
Vol 12 (3) ◽  
pp. 181-192 ◽  
Author(s):  
Pinar Yazgan ◽  
Deniz Eroglu Utku ◽  
Ibrahim Sirkeci

With the growing insurrections in Syria in 2011, an exodus in large numbers have emerged. The turmoil and violence have caused mass migration to destinations both within the region and beyond. The current "refugee crisis" has escalated sharply and its impact is widening from neighbouring countries toward Europe. Today, the Syrian crisis is the major cause for an increase in displacement and the resultant dire humanitarian situation in the region. Since the conflict shows no signs of abating in the near future, there is a constant increase in the number of Syrians fleeing their homes. However, questions on the future impact of the Syrian crisis on the scope and scale of this human mobility are still to be answered. As the impact of the Syrian crisis on host countries increases, so does the demand for the analyses of the needs for development and protection in these countries. In this special issue, we aim to bring together a number of studies examining and discussing human mobility in relation to the Syrian crisis.


Author(s):  
Sanja Milivojević

This chapter looks at the intersection of race, gender, and migration in the Western Balkans. Immobilizing mobile bodies from the Global South has increasingly been the focus of criminological inquiry. Such inquiry, however, has largely excluded the Western Balkans. A difficult place to research, comprising countries of the former Yugoslavia and Albania, the region is the second-largest route for irregular migrants in Europe (Frontex 2016). Indeed, EU expansion and global developments such as wars in Syria, Afghanistan, and Iraq have had a major impact on mobility and migration in the region. The chapter outlines racialized hierarchies in play in contemporary border policing in the region, and how these racialized and gendered practices target racially different Others and women irregular migrants and asylum seekers. Finally, this chapter maps the impact of such practices and calls for a shift in knowledge production in documenting and addressing such discriminatory practices.


2021 ◽  
pp. 019791832199478
Author(s):  
Wanli Nie ◽  
Pau Baizan

This article investigates the impact of international migration to the United States on the level and timing of Chinese migrants’ fertility. We compare Chinese women who did not leave the country (non-migrants) and were subject to restrictive family policies from 1974 to 2015 to those who moved to the United States (migrants) and were, thus, “emancipated” from these policies. We theoretically develop and empirically test the emancipation hypothesis that migrants should have a higher fertility than non-migrants, as well as an earlier timing of childbearing. This emancipation effect is hypothesized to decline across birth cohorts. We use data from the 2000 US census, the 2005 American Community Survey, the 2000 Chinese census, and the 2005 Chinese 1 percent Population Survey and discrete-time event history models to analyze first, second, and third births, and migration as joint processes, to account for selection effects. The results show that Chinese migrants to the United States had substantially higher childbearing probabilities after migration, compared with non-migrants in China, especially for second and third births. Moreover, our analyses indicate that the migration process is selective of migrants with lower fertility. Overall, the results show how international migration from China to the United States can lead to an increase in migrant women’s fertility, accounting for disruption, adaptation, and selection effects. The rapidly increased fertility after migration from China to the United States might have implications on other migration contexts where fertility in the origin country is dropping rapidly while that in the destination country is relatively stable.


2021 ◽  
pp. 152700252098832
Author(s):  
Alexander Genoe ◽  
Ronald Rousseau ◽  
Sandra Rousseau

This study uses Google Trends data to analyze the impact of the main events in the Tour de France 2019 on cyclists’ online popularity in 12 countries and at a global scale. A fixed effects panel model revealed a strong own-country preference. While online popularity increased with the duration of the Tour, race incidents strongly influenced online popularity. Besides the yellow jersey, winning a stage was more important than wearing the green, white or polka dot jersey for most regions. Still, on a global scale, young cyclists’ online popularity benefited more from wearing the white jersey than from winning a Tour stage.


2012 ◽  
Vol 46 (1) ◽  
pp. 139-153 ◽  
Author(s):  
EMILIA MARÍA DURÁN-ALMARZA

The Dominican American community in New York is perhaps one of the best examples of how processes of transculturation are affecting traditional definitions of ethnic identification. Given the intense economic, social and cultural transnational exchanges between the island and the USA from the 1960s, Dominicanyorks have been challenging the illusion of homogeneity in the definition of Americanness for decades, creating transnational social networks that transcend traditional national and ethnographic boundaries. The theatrical works of Josefina Báez, a Dominican American performer living in New York, and Sherezada (Chiqui) Vicioso, a Dominican poet and playwright who lived and worked in the US metropolis for decades before moving back to the Dominican Republic, lyrically explore issues of diaspora, identity and migration and the impact these phenomena might have in the lives of migrant Dominican women. Presenting diasporic experiences from two differing but interconnected locales – New York and the Dominican Republic – these plays offer two complementary views on the ways in which ethnicity, race, social class, age and geopolitical location interact in the formation of transcultural identities, thus contributing to develop a hemispheric approach to the study of identity formation in the Americas.


2013 ◽  
Vol 13 (24) ◽  
pp. 12215-12231 ◽  
Author(s):  
Z. S. Stock ◽  
M. R. Russo ◽  
T. M. Butler ◽  
A. T. Archibald ◽  
M. G. Lawrence ◽  
...  

Abstract. We examine the effects of ozone precursor emissions from megacities on present-day air quality using the global chemistry–climate model UM-UKCA (UK Met Office Unified Model coupled to the UK Chemistry and Aerosols model). The sensitivity of megacity and regional ozone to local emissions, both from within the megacity and from surrounding regions, is important for determining air quality across many scales, which in turn is key for reducing human exposure to high levels of pollutants. We use two methods, perturbation and tagging, to quantify the impact of megacity emissions on global ozone. We also completely redistribute the anthropogenic emissions from megacities, to compare changes in local air quality going from centralised, densely populated megacities to decentralised, lower density urban areas. Focus is placed not only on how changes to megacity emissions affect regional and global NOx and O3, but also on changes to NOy deposition and to local chemical environments which are perturbed by the emission changes. The perturbation and tagging methods show broadly similar megacity impacts on total ozone, with the perturbation method underestimating the contribution partially because it perturbs the background chemical environment. The total redistribution of megacity emissions locally shifts the chemical environment towards more NOx-limited conditions in the megacities, which is more conducive to ozone production, and monthly mean surface ozone is found to increase up to 30% in megacities, depending on latitude and season. However, the displacement of emissions has little effect on the global annual ozone burden (0.12% change). Globally, megacity emissions are shown to contribute ~3% of total NOy deposition. The changes in O3, NOx and NOy deposition described here are useful for quantifying megacity impacts and for understanding the sensitivity of megacity regions to local emissions. The small global effects of the 100% redistribution carried out in this study suggest that the distribution of emissions on the local scale is unlikely to have large implications for chemistry–climate processes on the global scale.


Author(s):  
Begüm Aylin Önder

Corporate social responsibility is one of the activities that goes beyond philanthropy, based on volunteerism in line with the responsibilities of enterprises towards society. This concept, which offers businesses the opportunity to look after and develop their brand image in the eyes of society, has become a necessity, not a choice, especially in today's world. In order to meet social expectations, the effectiveness of static and dynamic advertising messages implemented in all social benefit-based studies for human development such as environment, health and education is very important in terms of ensuring audience communication. In the second half of 2019, people were confined to homes and life came to a standstill all over the world in order to reduce and prevent the impact of the pandemic within the scope of the “New Type Corona Virus” (COVID-19) measures, which are from the sars-cov-2 coronavirus family, which is spreading rapidly globally starting from Wohan, Hubei Province, China. As a basic protection module for humanity against corona virus, it has incorporated the concept of social distancing into their lives in order to reduce the contact of staying at home and increasing hygiene, except in mandatory situations. During this extraordinary period, many brands on a global scale have included the concept of “social distance” in their advertising messages with the awareness of corporate social responsibility and have started to inform and educate the community about this issue by emphasizing the importance of the process. Within the scope of this research, advertising designs prepared by brands acting with corporate social responsibility awareness through the concept of social distancing during the Pandemic period were discussed and how the meaning structures behind the messages were created and transmitted. The research is limited to 3 (three) advertising designs determined by the 'judicial sampling' method (selective method). In the sample of the study, advertising narratives of brands in different sectors were explained in general framework and similar and different aspects of messages were uncovered by performing comparative analysis between messages in line with the findings obtained from the narratives. In this context, it was determined that the contrasts of “pessimism and optimism, hope and despair, happiness and unhappiness, death and life, strong and powerless, youth and old age, unity/togetherness and separation, struggle and defeat, nature and culture” were constructed as the main discourse.


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