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Download PDF File Science Horizon Volume 6 Issue 4 April, 2021 President, Odisha Bigyan Academy Editorial Board Sri Umakant Swain Prof. Niranjan Barik Prof. Ramesh Chandra Parida Editor Er. Mayadhar Swain Dr. Choudhury Satyabrata Nanda Dr. Rajballav Mohanty Managing Editor Dr. Nilambar Biswal Er. Bhagat Charan Mohanty Language Expert Secretary, Odisha Bigyan Academy Prof. Sachidananda Tripathy HJCONTENTS HJ Subject Author Page 1. Editorial : Uttarakhand Glacial Burst-A Warning Er. Mayadhar Swain 178 2. The Star World Prof. B.B. Swain 180 3. Role of Physics in Information and Communication Dr. Sadasiva Biswal 186 Technology 4. National Mathematics Day, National Mathematics Binapani Saikrupa 188 Park & Srinivasa Ramanujan 5. A Brief History of Indian Math-Magicians (Part IV) Purusottam Sahoo 192 6. Glacier Dr. Manas Ranjan Senapati 197 7. Do Plants Recognise their Kins? Dr. Taranisen Panda 198 Dr. Raj Ballav Mohanty 8. Paris Climate Agreement and India’s Response Dr. Sundara Narayana Patro 201 9. Fluoride Contamination in Groundwater with Jayant Kumar Sahoo 205 Special Reference to Odisha 10. Electricity from Trees Dr. Ramesh Chandra Parida 209 11. Hydrogen as a Renewable Energy for Sustainable Prof. (Dr.) L.M. Das 212 Future 12. Nomophobia Dr. Namita Kumari Das 217 13. Quiz: Mammals Dr. Kedareswar Pradhan 220 14. Recent News on Science & Technology 222 The Cover Page depicts : Green Hydrogen Cover Design : Kalakar Sahoo APRIL, 2021 // EDITORIAL // UTTARAKHAND GLACIAL BURST- A WARNING Er. Mayadhar Swain On 7th February 2021, a flash flood occurred in Chamoli district of Uttarakhand villagers, mostly women, were uprooted in causing devastating damage and killing 204 this flood. At Reni, Risiganga joins the river persons. There are many glaciers in the high Dhauliganga and so there was flood havoc mountains of the Himalayas. The glaciers form downstream Dhauliganga. The flood washed lakes bounded by ice, sand and stones. When away many villages and damaged two under the glacier melts, the water is released construction hydropower plants. The power suddenly. It is called Glacial Lake Outburst plants are 13.2 MW Rishiganga power plant Flood. The ice dam of glacial lakes are of on the river Risiganga and 520 MW Tapovan weak structure and the failure of the same has Vishnugad Power Project of National Thermal the potential of releasing millions of cubic Power Corporation on the Dhauliganga river. metres of water in a short period, causing At Dhauliganga Project, the avalanche trapped catastrophic floods downstream. Water flow several workers working on the barrages and as high as 15000 cubic metre per second has inside the tunnel to divert the natural flow of been recorded in the past. The recent the Dhauliganga. Some other hydropower plant Uttarakhand flash floods occurred due to the dams were also damaged in the flood. burst of a glacial lake in Rishiganga inside Although the disaster seems natural from Nanda Devi Sanctuary. outside, it can well be considered as man- It is believed to have been caused by a made. In fact this has the fingerprints of global landslide, an avalanche or glacial lake outburst. warming for which human is responsible. After According to Planet Labs, ice along with frozen industrial age started in the middle of the mud and rocks fell down from a high mountain eighteenth century, the amount of carbon inside the Nanda Devi Sanctuary from a height dioxide and other greenhouse gases have 5600 metre to 3300 metre. This created an increased in the atmosphere due to which the artificial lake within the sanctuary in Rontigad, global temperature is increasing. Due to rise a tributary of Rishiganga. Within eight hours, of temperature, the ice sheets in glaciers are this lake burst open and its water laden with melting and hence the glaciers are gradually mud and stones rushed through the Rishiganga receding. The flash floods are the cause of gorge which opens near the village Reni. It is this. Another reason of the devastating flood the same village which was famous for Chipco is deforestation in the Himalayan region. Movement 51 years ago in 1970 and Deforestation, although for development unfortunately many of the trees saved by the purpose, has its ill effects. There are many 178 Science Horizon APRIL, 2021 hydropower plants established in this region that the glacial burst is due to melting of ice, and some are either in construction or planning which is an effect of global warming and stage. Damming the rivers deposits silts on climate change. The whole world is now facing the rivers which restrict their capacity during the ill effects of this in some way or other. We floods. Further, deforestation causes washing are now witnessing increasing number of of soils. A number of trees have been felled in cyclones, tornadoes, drought period etc due to Uttarakhand for construction works. When this. The small islands and low-lying coastal Uttarakhand was carved out of the undivided areas are threatened to be submerged. On Uttar Pradesh, it had 19,449 km of roads and February 13 this year, a severe cold snap crashed now after 20 years its total road length is the electricity grid system in Texas, USA 39,504 km. For one kilometre of road plunging most part of the state into darkness. construction 20 to 60 cubic meter of debris is Scientists have attributed this to climate change. generated and from this one can imagine how The collapse occurred due to extreme cold much debris must have gone to the river thereby weather in the area. The gas in well and restricting the flow of water. pipelines was frozen and the thermal power This is not the only devastation of nature plants stopped operating. The Arctic peninsula in recent times. There have been number of is warming at a rate almost twice the global such type of natural calamities, small or big, average. Usually, there is a collection of winds in the recent past. The most notable one was around the Arctic keeping the cold locked for the 2013 Kedarnath flood in which about 6000 the north. But global warming has caused gaps persons had died. The expert committee which in these protective winds, allowing intensely investigated this had given some proposals cold air to move south. This caused the black which are yet to be carried out. In fact, in the out in Texas. past there were many scientific studies on the The 2015 Paris Agreement is an excellent glaciers and the probable effect of its burst. treaty for mitigation of climate change. Almost The fact is that no committee has given any all the countries have voluntarily committed firm decisions with convictions. For instance, to reduce carbon emission. But they have not geologists suggest the Himalayan rivers should achieved the target. Of course, India, the third not be dammed to construct hydropower plants. largest emitter of carbon after China and USA, But they have no concrete evidence against it. is progressing well as per its programme and As a result, there are many such plants coming will fulfil its target by due date. The in both Uttarakhand and Himachal Pradesh. In Uttarakhand deadly disaster has given a warning Uttarakhand alone 58 hydropower plants with not only to India, but to the whole world to act. about 1500 km length of tunnel are under Otherwise, we may expect many disasters in construction. the future. If we do not act now, there will be We can take the Uttarakhand glacier blast no time in future to control it. So stop carbon as a warning. There are 9575 glaciers in the emission and save the world. Himalayas covering about 37,466 sq.km, which FG may affect India, China, Pakistan, Bangladesh Er. Mayadhar Swain and Myanmar. Scientists agree on one point Editor Science Horizon 179 APRIL, 2021 THE STAR WORLD Prof. B.B. Swain Looking at the night sky, with no clouds and no moon, you will find innumerable Here on the ordinate is plotted the luminous points spread across it. These point spectral class of any given star, while on the sources of light are named as stars. Of course, abscissa is plotted its luminosity with respect planets also appear as luminous point, but they are few in number and emit steady light whereas light from the stars flicker to some extent that is easily observed. On viewing the stars, even with most powerful telescope, we can not find any difference among them. But in reality, the stars belong to different types and classes similar to the population of a city which can be grouped separately adopting different criteria such as young-old, colour, religion, height, weight etc. During World War-I, two astronomers in different parts of the world the American Henry Morris Russel and Dutchman Ejnar Hertzsprung, unaware of Fig.1: Hertzsprung-Russell diagram for 230 brightest stars, showing the break-up into (normal) Main Sequence each other’s work, were trying to know Stars, Red Giants, and White Dwarfs how the surface temperature (i.e. spectral to Sun in terms of absolute magnitude. The class) of different stars are correlated with most striking feature of the HR diagram is a their intrinsic brightness (i.e. absolute rather narrow band running from the upper left luminously). The result was the famous corner to the lower right corner. Stars placed Hertzsprung-Russel (HR) diagram, Fig.-1. in this band are known as “Main sequence 180 Science Horizon APRIL, 2021 stars” and our Sun sits roughly in the middle rapid proper motion in the sky, travelling at of the band. The upper end of the main the rate of about 140 km/s in the direction of sequence contains very bright stars with such earth.
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