The discovery of ozone (O3) in the troposphere was first made in the 1840’s. Consequently, an intensive study about its distribution was made in the latter part of the nineteenth century due to its supposed health giving properties as a germicide (Schönbein, 1840). The first classical explanation of ozone in the troposphere was that it was made in the stratosphere by direct photolysis of oxygen at wavelengths less than 242 nanometer.
Stratosphere is a layer above the earth’s surface, between approximately 15 and 50 km. It was believed that once the ozone is formed, it is transported downward from the stratosphere to the troposphere, to be ultimately destroyed in contact with the earth’s surface, particularly land surfaces. Although it became known that there was a direct source of ozone in the troposphere in photochemical smogs (first discovered in Los Angeles in the 1940s) it was not understood to be significant on a global scale.
This classical view of the origin of ozone in the troposphere underwent a complete turnaround during the course of time. It is now well documented that ozone is produced in two regions of the earth’s atmosphere. Most ozone—about 85-90 percent, resides in the stratosphere, commonly known as the ‘ozone layer’. The remaining ozone is in the lower regions of the atmosphere—the troposphere, which extends from the earth’s surface up to about 8 km near the poles and ~18 km near the equator. Ozone from both these regions have the same chemical composition (three oxygen atoms), but their effects on humans and other living things are very different. Based on their location ozone can either protect or harm life on earth. Low lying ozone is a pollutant and a key component of smog, a familiar problem in cities around the world. Higher than usual amounts of surface ozone is now increasingly being observed in rural areas as well.
Denne historien er fra June 1-15, 2019-utgaven av Geography and You.
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Denne historien er fra June 1-15, 2019-utgaven av Geography and You.
Start din 7-dagers gratis prøveperiode på Magzter GOLD for å få tilgang til tusenvis av utvalgte premiumhistorier og 9000+ magasiner og aviser.
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Covid-19: Politics Of Knowledge, Public Health And The World Order
In the present era of a knowledge society, the world order will be shaped more than ever before by the politics of knowledge. In the post-CoVId world, public health knowledge is likely to be a significant contributor. This article briefly discusses the various contemporary public health approaches evident within the discipline: global health, community medicine and critical public health. Then it goes on to analyse country level policy approaches to the COVID-19 pandemic, delineating a tentative four-category typology, based on available information. Finally, it sets out the possible outcome indicators that should be used to assess the national responses.
WILD MEAT AND WET MARKETS: A GLOBAL DIALOGUE
Wet markets operate in most Asian countries including India. China reported its wet markets as the epicentre of the Covid-19 outbreak in Wuhan and also more recently in Beijing. These wet markets, a traditional part of popular local culture in Asian countries, are increasingly becoming a cause of concern for the international community and health practitioners across the globe. This article attempts to understand how global authorities and their Asian partners are looking to regulate these infamous wet markets to significantly lower the risk of viral and other pathogenic load from these unhygienic wet markets.
SEA WALL IN THE MALDIVES AND ITS SUSTAINABILITY
The Small Island developing states are particularly vulnerable to the peril of climate change. Sea level rise, increase in sea surface temperature, high incidences of drought and flood are some of the vulnerabilities that loom large over such island states.The republic of Maldives is one such example, which has been publicly advocating for the reduction in greenhouse gas emissions. Despite being one of the least contributors to such emissions, the Maldives faces the highest impact of global warming. Being one of the lowest-lying island nations, it has been undertaking various steps to curb the egregious impacts of environmental catastrophes.One of the response measures taken by the Maldives is the construction of seawalls. This article discusses this, while accenting the drawbacks and benefits associated with the approach.
TO PLUCK AT WILL: FRUIT TREES IN COMMON PROPERTY
Despite many governmental initiatives, malnutrition in India remains a major health challenge. There is a marked deficit of fruits in the diet of most Indians, consuming much lower than what is recommended by the World health organisation (Who). One of the reasons behind this is the high price of fruits and thus its inequitable access. As we prepare ourselves to live in a world marred by COVID-19 and a shrinking Indian economy, we must think of new ideas to manage access to food, especially micro nutrient rich fruits. This paper explores the possibility of planting endemic fruit trees in public spaces like roadsides and parks, that can help in increasing the consumption of fruits amongst the poor. It also attempts to analyse whether this can serve as a long term solution to bridge the gap between fruit production and consumption in India.
RESPONSIVE URBAN PLANNING: COVID-19 A TURNING POINT FOR REAL CHANGE IN INDIAN CITIES
The global challenge of COVID-19 is still unfurling. States are grappling to control its remorseless spread with varied success and its impact both on long and short-term scales are still being understood. However, a distinct urban bias in its spread across the globe and universal response of lockdown and social distancing for its control has brought pertinent questions to the fore. Urban planning and the future of our cities in terms of urban life and city form therefore needs to be revisited. In India, the exodus of migrant workers from its large cities has added yet another dimension to this challenge.
PAUSE AND REBOOT
REFLECTIONS ON ECONOMY, SOCIETY AND POLITY DURING COVID-19 GLOBAL PANDEMIC AND LESSONS FOR INDIA
Migrants & borders: My wishlist in a post-Covid-19 world
Former Professor of Economics and Education, School of Social Sciences, Jawaharlal Nehru University, New Delhi. bkhadria@gmail.com.
Inequalities in Access to Academic Spaces
Experiences of students from the socially excluded groups in higher education in India
Understanding Caste and Class - Categories and Measurement
The caste has been a unique social institution in India. It has also emerged in a new form after the mandalisation of caste in the early 1990s resulting in the extension of reservation to Other Backward Classes (OBCs) in government jobs and also in admissions to colleges and universities. The relative size of population of various caste groups particularly of the OBCs is also a matter of debate. Census does not provide population data on OBCs, however, it is possible to assess it from nationally representative sample surveys. Further, the correspondence between caste categories and class has been a matter of debate. This paper presents an assessment of class within caste categories based on data from nationally representative sample surveys.
The Middle Class - As the Class of No Class
An attempt to understand some of the ambiguities around what it means to be middle class in India has been made in this paper. It also discusses the influence that the middle class supposedly has on Indian politics despite these uncertainties.
