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A comprehensive high‑resolution gridded emission inventory of anthropogenic sources of air pollutants in Indian megacity Kolkata
Get PDFIn this study, we present a first-ever effort made to develop an ultra-high-resolution gridded emission inventory
(i.e. ~ 0.4 km × ~ 0.4 km) for the Indian megacity Kolkata. As the rising demand for fossil fuels based energy along with
the spread of urban corridors have forced the anthropogenic activities to a mounting level, therefore determining the
sources responsible is of paramount importance. This has worsened not only the regional air quality but also has an
indirect effect on the global air quality. The spatial and temporal variation of the source requires an accurate estimation
of the surface emission which is the most essential parameter to study the air quality, that positively has been fulfilled
in this study. The annual emission for 2020 is calculated to be 37.2 Gg/yr of PM2.5,
61.4 Gg/yr of PM10,
222.6 Gg/yr of CO,
131.3 Gg/yr of NOx, 60.3 Gg/yr of SO2,
120.4 Gg/yr of VOC, 9.5 Gg/yr of BC and 16.8 Gg/yr of OC that prevails in the toxic
air of megacity Kolkata. The present surface chemistry dataset will be the first line of detailed information regarding
emission hotspots in the megacity that could be used as important tool for clean air mitigation strategies, input into the
air quality modeling study to tackle environmental issues, and public health
Geospatial Modelling for Estimation of PM2.5 Concentrations in Two Megacities in Peninsular India
Get PDFAirborne particles finer than 2.5 microns (PM2.5) constitute a major public health risk in India. Therefore, extensive scientific studies must be conducted to assess the PM2.5 exposures of Indians and determine the “exposure-response function” specific to India. While Peninsular India includes three megacities with populations exceeding 10 million each, there are very few studies on air quality modelling in this region compared to North India. In this paper, the authors describe a Linear Mixed Effects (LME) model to estimate monthly-average PM2.5 concentrations at a spatial resolution of 1 km2 between 2016 and 2019 in the megacities of Bengaluru and Hyderabad with a total population of 23 million. This model is based on covariates such as aerosol optical depth (AOD), meteorological parameters, and Land-use-Land-cover (LULC) variables and is validated with extensive datasets from continuous and manual air quality monitoring stations through a 10-fold cross-validation process. The final LME model can explain more than 60 percent of the variation in the PM2.5 concentrations in Bengaluru and Hyderabad. This model is then used to predict the monthly-average grid-wise PM2.5 concentrations in more than 800 grids in each of these two cities to study the spatial and temporal patterns in PM2.5 concentrations between 2016 and 2019. These spatiotemporal maps of PM2.5 concentration are critical to overcoming the misclassification of exposure and will form a crucial input to much-needed PM exposure-response studies in these two megacities. This paper can serve as a useful framework for similar studies by showing the way to bridge the gaps in the current air quality monitoring network in Peninsular India
Ancient Indian Metallurgy
No full textThis talk (Episode #50) by Prof Sharada Srinivasan is a part of the bimonthly programme series on Traditional Knowledge Systems - Power of Listening by Akashvani. This series attempts to touch upon the rich legacy of science, mathematics and technological practices in ancient and medieval India that serves as a bedrock for shaping our present
Far from home: The synurbisation of a rainforest-evolved primate, the lion-tailed macaque Macaca silenus, and its recent adaptations to anthropogenic habitats in southern India
No full textThe lion-tailed macaque is an endangered species, endemic to the Western Ghats of southern India. The Anamalai hills harbour 63 groups of the species, several of which occur in rainforest fragments, amidst tea and coffee plantations, on the Valparai plateau. Being highly arboreal, these populations have always been assumed to be largely restricted to their fragmented forest patches and possibly unable to navigate successfully through the surrounding plantation–human habitation matrix. While adult males have occasionally been sighted along roadsides between forest fragments, we now provide evidence for the emigration of an entire troop out of a forest fragment into nearby human settlements, leading to the inclusion of areas completely devoid of natural vegetation into the core home range of the troop. We argue that a combination of hostile inter-troop encounters, a natural urge to expand their range and the discovery of novel and relatively easily accessible food resources may have led to such unusual ranging patterns, accompanied by significant changes in troop behavioural profiles, which we consider as inexorable processes of synurbisation
Is ultraviolet Radiation a Confounding Variable for COVID-19 in India?
Get PDFThe current global Coronavirus disease (COVID-19) became a pandemic due to its contagion
nature and rapid spread throughout the world. The pandemic caused a lockdown resulting in a
large decline in the level of anthropogenic emissions of tiny aerosol particles that altered
the solar irradiance and decreased the quantity of aerosol, which opposes global warming.
This study first demonstrates that surface ultraviolet radiation (UV) increased significantly
during the lockdown period in four major Indian mega cities, whose magnitude varies based
on city demography. Results shows that the correlation between the high rate of increase in
Ultraviolet irradiance (UV-irradiance) on mortality and morbidity. Although there are
numerous confounding factors for the pandemic, UV-irradiance could be one of the factors
supporting the hypothesis that increased solar UV dose may increase rate of disinfection as
radiation warps the structure of genetic material of the virus and deactivates it. Another factor
which also have potential to add up increase of Vitamin D3 production per minute of
exposure due to UV-irradiance resulting in an increased human immune system to fight
COVID-19 more effectively. However, it is cautioned here that a high dose of direct UV
exposure to humans may be fatal leading to skin damage and melanoma cancer. Hence, the
harmful impact of UV-Irradiance on the human body and its application to possible
disinfectant to virus deactivation should be understood in a proper perspective
A Review of Human Reliability Programs for Nuclear Security
No full textHuman Reliability Program (HRP) is a set of procedures, protocols, and the corresponding performance of activities to support and sustain the secure and safe operation of a facility. Our review indicated that HRP is referred to by various names, such as, Personnel Reliability Program (PRP), Trustworthiness Program, and Fitness for Duty Program, with PRP being the most common amongst them. A brief description of the evolution of HRP and its components for Finland, Japan, Jordan, Nigeria, Russia, US, and UK is provided. Details of the Trustworthiness Program by the International Atomic Energy Agency are also provided. Most of the HRPs have similar components and implementation steps with few variations, and they all have identical objectives. Even though a structured HRP may not exist in Indian civil nuclear energy facilities, an account of various HRP components practiced in India is discussed. The HRP review provided should help security practitioners and academics
Geoenvironment and weathering of silicate minerals in sediments of the Brahmaputra river, India: Implications for heavy metal pollution assessment
Get PDFWe carried out detailed compositional studies on fifteen sediment samples from the Brahmaputra River that were collected in the pre-monsoon period, to obtain the inherent contamination factor. The present study demonstrates that the degrees of metal contamination in the sediments of the Brahmaputra river. Typical metals Fe, Al, Ti, Pb, Zn, Cu, Ni, Co, Mn and Cr, have been evaluated using several parameters like, enrichment factor (EF), contamination factor (CF), geo-accumulation index (Igeo) and pollution load index (PLI). The relative distributions of the contamination are found to be: Al > Fe > Ca > Mg > Ti > Mn > Cr > Cu > Zn > Ni > Pb > Co. The suspended sediments have been found to be moderately contaminated by the elements Cu, Pb, Cr, Mn and Ni. The nature of weathering is estimated using plagioclase index of alteration (PIA), chemical index of alteration (CIA), chemical index of weathering (CIW) and index of compositional variation (ICV). The studied suspended sediment samples indicate an intermediate silicate weathering of adjoins area
Towards the instrumentality of inequality
No full textWhat has been the nature of work and discourse on inequality in India? Has it been more anecdotal and ordinal? Does it sidestep the conceptual and reflective? Is it an elite discourse even within the subaltern? Does it remain blind to both the subtleties and the macro forces that generate, fuel, and reproduce the condition of inequality? and importantly, has it seriously considered the issue of what inequality does to those at the margins? The recent Dadabhai Naoroji conference at NIAS, on the instrumentality of inequality raised these conceptual, ethical and practical dimensions of inequalit
Spectroscopic Investigations and Mineral Chemistry of Dunite from the Sargur Supracrustals (3 Ga) Greenstone Belt: Implications to Terrestrial Analogues for Lunar and Martian Dunite
Get PDFArchean Serpentinised dunite is important not only for
understanding the evolution of the ultramafic deposit of
magnesium, but also serves as a possible sink material for the carbon dioxide sequestration. Future anti-pollution measures may include sequestering of waste CO2 as magnesite (MgCO3) by processing ultramafic rocks to obtain reactable Mg. For the first time, the Raman spectroscopic investigation of dunite is presented from the Karya, Sargur supracrustals (3Ga) Greenstone Belt. The Raman spectra of the sample reveal abundant presence of serpentine. Polymorphs of serpentine: lizardite, antigorite and chrysotile exhibit typical intense band at 685–692 cm–1 in the Raman spectrum. The Raman peaks in this study also indicates the presence of chromite and magnesite. The lunar dunite 72415, one of the oldest lunar samples of the Mg-suite, contains chromite symplectites indicative of crystallization at 40–50 km rather than
at a shallow depth of <1 km, also having a olivine content of about 85%. The present study showed the dunite has about 85%
olivine, which is almost identical to the Martian dunite, meteorite Northwest Africa (NWA) 2737 is the second known chassignite, an olivine-rich igneous rock with mineral compositions and isotopic ratios that suggest it formed on Mars. NWA 2737 consists of ~ 85% vol. The present study on the Karya dunite of Sargur supracrustals (3 Ga) greenstone belt, Western Dharwar Craton Karnataka, indicates a possibility of using this as a terrestrial analogue material for improving the Martian surface mineralogy and occurrence of hydrous minerals and life support system in Mars
Subject choice and STEM careers for women in India
No full textTHE last few decades have witnessed concerted efforts from countries worldwide to increase the participation of women in higher education with a specific focus on science, technology, engineering, and mathematics (STEM). The central driving factor has been that women constitute half of the world’s population; hence, this needs to be reflected in all domains, including the STEM disciplines. Another factor that has propelled this drive is that diversity will positively impact the development of these disciplines.
This paper aims to investigate the determinants that motivate women scientists in India to choose the STEM disciplines to build a career. The existing literature based on data mainly from western countries highlights that there are not enough women in the STEM disciplines. The most common reason that has been cited for this problem is that there are not enough women role models that can inspire women to join the STEM disciplines.
However, in India, the data suggests that the number of women in STEM disciplines at the undergraduate and postgraduate levels is equivalent to that of men. Even at the PhD level, women are not very far behind. Despite the data telling a success story, the Indian case is interesting as the ‘leaky pipeline’ does not disappear but shifts to the doctoral level, which is even more worrisome. The missing women in STEM after acquiring the highest level of training is a national loss. The increased number in enrolment of women in the STEM disciplines does not translate to the representation of women in academia or research laboratories in the industries. Women, in particular, are conspicuously nearly absent at prestigious national-level research institutes in the country