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The Melting Of Himalayan Glaciers

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Syskool
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The Melting Of Himalayan Glaciers

 

Every conscious human being is today well aware of the fact that global warming will prove catastrophic in the near future if the rate of warming goes unchecked for a long time. Particularly, scientists are more concerned,
because they have succeeded in their effort to identify the factors responsible for this unpleasant but real phenomenon. Across the globe, lots of measures have been contemplated and the leaders of all important nations have arrived at the conclusion that global warming should be retarded and finally stopped in a phase-wise manner. Which country has to resort to what and to what extent have not yet been decided, but no country denies the fact that global warming has been caused by man and man has to do everything to curb it if life has to continue on this planet. Groups of scientists, environmentalists, NGOs and other different forums have unanimously expressed almost the
same view throughout the world. However, different views are expressed on the relation between global warming and ozone depletion or global warming and glacial retreat. Points and counterpoints pour in and the common people get confused. For example, an official discussion paper on the status of Himalayan glaciers had created a controversy owing to the argument that Himalayan glaciers which nourish several great rivers such as the Indus, Ganges, and the Brahmaputra, have not retreated abnormally. This paper had been issued by the Ministry of Environment and
Forests, Government of India a couple of years ago. Besides, the statement made by the Union Minister of State for Environment and Forests, Mr. Jairam Ramesh added fuel to the controversy. According to his statement, there was no conclusive evidence to show that global warming was responsible for the glacial retreat. His view
challenged the findings of the Intergovernmental Panel on Climate Change (IPCC). This Nobel Prize-winning international body of scientists, the IPCC, had released its comprehensive Fourth Assessment Report on Climate Change two years ago prior to it. The Report clearly pointed out that glaciers and ice caps provided the most visible
indications of the effects of climate change. TheHimalayan glaciers were receding faster than in any other part of the world.The Himalayas have the largest concentration of glaciers outside the polar region. These glaciers cover an area of 33,000 km. Seven of Asia’s greatest rivers including the Brahmaputra, Ganges and Indus are fed with this water.

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We should not lose track of the fact that the water availability downstream depends to 50% on snow and glacial
melting both in short and long terms. Studies have shown that most of the Himalayan Glaciers are melting faster than the world average and are endangered to melt in the next 40 years.Studies have found that approximately 67 percent of Himalayan glaciers are retreating with an alarming rate. For example, in the last few decades, 82 percent in West China have retreated. With decreasing ice and snow and with them water storages, in the high altitudes, the water availability downstream will more and more depend on the direct run- off from rain and oil evaporation rates. So, there will be water shortages in dry seasons. Due to glaciers’ retreat, the glacial lakes will grow rapidly and at the same time, new glacial lakes will occur. Glaciers are generally considered to be highly efficient agent of erosion. Glaciers tend to remove all the weathered and easily erodible rock and soil and leaving behind valleys with fresh hard walls, hard to erode.That is why, the erosive potential of rivers is less effective in new glacier ­shaped valleys, than in comparable regions without recent glacial history. Glacier-fed rivers are mostly loaded with a high
amount of sediment and sediment load increases the erosion potential. On the other hand, sediments accumulate at the bottom of U-shaped valleys with low-gradient floors and decoupling the hill slopes from the channels and therefore as well from the destructive force of rivers. It is because of this that in some areas, the erosive force of glacier-fed rivers is reduced. Denudation rates are higher in glaciated regions than in unglaciated. Moreover, cold dry conditions slow down erosion dramatically. It is due to this that the erosion rate in the northern high Himalayas is extremely lower today than it was during times of widespread glaciation. Warmer climate would increase chemical weathering and biotic activity in the watersheds at the timescale of 102-103 year and produce easily erodible material in the high altitudes.Climate change of global warming, however, affect the hydrological conditions and glaciology. Increasing temperature causes the following : a warmer air has the ability to contain more moisture. The availability of water increases the rate of evaporation. That is why the water vapour in the atmosphere is on the rise. The moisture in the atmosphere acts like greenhouse gases. Besides, with warmer air and water temperatures, the loss of snow and ice by melting is growing. The snow and ice cover have decreased which has been noticed more clearly during spring and summer. During summer, melting is faster than in winter, because compared *to winter more sunlight is absorbed in summer. With bigger warming of the earth surface a rising long-wave radiation occurs
and this causes an increase of air temperature. The precipitation changes in intensity. The precipitation form is changing from snow to rain. As a result of higher melting rate of snow and ice, the soil moisture is increasing. The modification of the discharge depends on changes in volume and timing of precipitation and the form of precipitation. The evaporation affects the run-off to decrease. The bigger melting rate affects the changes in glacier levels. The amount of changes depends on river inflows, precipitation, and evaporation.As we have already seen, the glacial retreat is the most significant impact of global warming in the mountain region. The glacial retreat can be measured by horizontal length changes or vertical through the thickness and volume changes. The glacier melting comprises several processes within the glacier, like changes in the glacier flow, basal sliding, and internal deformation. In addition, a rising air temperature has an effect on the mass and energy balance of the glacier surface. A melting glacier shows the appearance of surging and calving. Surging glaciers start all of a sudden and flow up to 100 times faster than usual. Thereafter, the glacier contains deep crevasses and disruptions on the glacier surface. Glacier retreating causes following hydrological impacts : Rising sea level; changes in run-off—increasing run-off resulting in floods and decreasing run-off, resulting in water stress and glacial lake formation. We have already discussed that the bigger melting rate results in bigger discharge of glacier-fed rivers. But, if the run-off of a glacier-fed river decreases, i.e. if the glacier gets smaller or disappears, the effect is water shortage in the catchment area.Read Also: Rivers, Waterfalls, and Glaciers

The Intergovernmental Panel on Climate Change pointed out in its comprehensive Fourth Assessment Report on Climate Change some years ago that if the Himalayan glaciers continued to recede at the rate existing at that time, there was a very high risk of their disappearing by the year 2035, perhaps sooner too. According to it, measures had to be taken to curb warming of the earth at the prevailing rate. It warned with a view to making people aware of the fact that water scarcity could affect more than a billion people in Asia itself. Water shortages, it is a common knowledge now, mean a big threat for 500 million inhabitants of the Indus, Ganges and Brahmaputra river basins, who rely on permanent supply of melt-water from the Himalayas. The problems of water stress are already or ‘never’ to this evil practice of prevalent in the region due to increasing demands of domestic consumption, agriculture, industry and an ever- increasing population. Any future reduction in the availability of freshwater would have serious consequences for the economy, environment and daily life of people living within the affected area. India has already power-shortages problem (10 percent total electrical energy, 20 percent of peak capacity requirements) and in view of rising demand of energy, the likelihood of inadequate hydropower in the future has serious implications for the development plans of the whole country. Industries like food processing, mining, paper, chemical and steel production would suffer badly, because they need a secured water supply.

The Ministry discussion paper which had given birth to a controversy regarding melting of Himalayan glaciers had been prepared by Mr. V.K. Raina, ex-Deputy Director General, Geological Survey of India. Though in the paper, he had agreed that glaciers in the Himalayas, except a few, had been in constant retreat since mid-19th century, they had in no way exhibited, especially in the recent years, an abnormal annual retreat of the order that some glaciers in Alaska and It would be, therefore, premature to state that these glaciers were retreating because of global warming. Mr. Raina also went on to say that the Gangotri glacier, which fed the Ganges, was practically at a standstill for the last two years. Mr. Rajendra Pachauri, Chairman, IPCC, criticised both the discussion paper and the then Union Minister of State for Environment and Forests, Mr. Jairam Ramesh. According to him, this research was unsubstantiated. As Syed Iqbal Hasnain, a leading glaciologist thought, the discussion paper was biased and unscientific. A group of scientists at Indian Space Agency’s Space Applications Centre, Ahmedabad used satellite images to study 466 glaciers in the Chenab, Parbati and Baspa basins. They found that the glaciers had shrunk by 21 percent since 1962. The report was published in 2007. Some time back, the space scientists had carried out a study and came to the conclusion that a one degree Celsius rise in temperature by 2040 would more than halve the area occupied by the glaciers which fed a particular tributary of Sutlej. Now, a layman is free to speculate whether global warming is related to the melting of Himalayan glaciers or not.


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Agricultural Sustainability And Green Farming

By
Syskool
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GENERAL ISSUES ON ENVIRONMENTAL ECOLOGY, BIO-DIVERSITY AND CLIMATE CHANGE
Agricultural Sustainability And Green Farming
If all the global issues are taken together, nothing draws more attention than political and economic upheavals as well as climate change and food security. While political and economic upheavals seem to be of temporary nature, climate change and food security are going to have long-term implications and call for both immediate and sustained effort by people across the globe, because both the issues are vital for our existence itself. Since the time man came to know about the benefits of organised living, he has unscrupulously used the bounties of nature and this practice continues in a great measure today also. Only a few conscientious people are determined to educate the vast majority on the dangers that are involved. Until not very long ago, the people, both laypersons and scientists were not aware of the phenomena like ozone depletion, extinction of numerous species due to loss of habitation and change brought about by human interference and the dangers that have been looming large over the centuries as a result of man’s insatiable passion for development which wreaks havoc in its wake. It is ironic that so long as man had been ignorant of modern farm practices, he had stuck to the farming that is now thought of being sustainable and beneficial in the long term. For example, organic farming was the original type of agriculture that had been practised from time immemorial. The other form of farming, called forest gardening which is a fully organic food production system which dates back to prehistoric times, is now thought to be the world’s most resilient agrosystem. It was in the mid-1920s in Central Europe that the work of Rudolf Steiner gave birth to an organic movement, because people became aware of the fact that the inorganic methods, introduced by the industrial revolution, were to some extent not well developed and had serious side effects too. Rudolf Steiner had introduced biodynamic agriculture which was a precursor of organic farming. What is referred to today as organic farming was, in fact, developed through the work of Albert Howard in England in the 1940s. Albert Howard had developed an aversion to agriculture’s growing dependence on synthetic fertilisers.
In his inauguration address at the 27th Indian Engineering Congress on the theme “Engineering for Sustainable Development and Inclusive Growth: Vision 2025” at Vigyan Bhavan, Delhi on December 14, 2012, Hon’ble President Mr. Pranab Mukherjee said that poverty and degraded environment are closely inter-related. He stressed the fact that several traditional practices »that are sustainable and environment- friendly continue to be part of the lives of people in the developing countries. According to him, these need to be encouraged, rather than replaced by more modern but unsustainable practices and technologies. He expressed the view that the integration of agriculture with land, water management, and ecosystem conservation is essential for both environmental sustainability and agricultural production.
When one talks of green farming or eco-farming stressed by the scientists and experts recendy, organic farming acquires a central place. It is the form of farming that relies on techniques such as crop- rotation, green manure, compost and biological pest control. Organic farming makes use of fertilisers and pesticides, but excludes or puts a limit on use of manufactured (synthetic) fertilisers, pesticides (which comprise herbicides, insecticides and fungicides), plant growth regulators such as hormones, livestock antibiotics, food additives, genetically modified organisms, human sewage sludge, and nanomaterial. The concept of clean or eco-friendly agriculture has caught the imagination of farmers in many countries and is being promoted by small, well-organised groups. But it is still not popular among the farm community in India. If we analyse, we find that some of the major farming States, e.g. Punjab and Haryana, have been laying more stress on mass production of food grain and other farm products. In their effort, they have never paid any importance to their quality and related aspects. They have been doing so, because of the fact some decades ago, India was an extensively food-grain- deficit country. India had to depend on the developed countries and imported food grain. If we look back, we find that before the 1960s, the use of pesticides was negligible. After the Green Revolution, pesticides became the indispensable part of farming. Farmers started extensive use of pesticides, weedicides and insecticides in the 1980s and by the mid-1990s they became synonymous with farming.

Organic farmers depend on biological pest control, the use of beneficial organisms to reduce pest populations. Examples of beneficial insects are minute pirate bugs, and to lesser extent, ladybugs, big-eyed bugs— which eat a number of pests. Besides, praying mantis and predatory mites are very effective in controlling other mites. When pests go out of control, organic farmers do use a pesticide. With some exceptions, naturally occurring pesticides are used by farmers and synthetic substances are prohibited. Pesticides with different modes of action should be rotated to minimise development of pesticide resistance. Naturally derived insecticides used for green and organic farming are Bacillus thuringiensis, pyrethrum (a chrysanthemum extract), spinosad (a bacterial metabolite), neem and rotenone (a legume root extract). Though rotenone and pyrethrum are sometimes referred to as green pesticides, yet they are not necessarily harmless, so they are used in very rare cases. They are however, safer and more eco-friendly than synthetic pesticides. Rotenone, it has been found, is extremely toxic to fish and can induce symptoms resembling those of Parkinson’s disease in mammals. Naturally derived fungicides used in organic farming include the bacteria Bacillus subtilis and Bacillus pumilus and the fungus Trichoderma harzianum. These are mainly effective for diseases affecting roots. Scientists have found that caprylic acid, naturally occurring fatty acid in milk and coconuts as well as other natural plant extracts have anti-microbial characteristics. Compost tea contains a mix of beneficial microbes which may attack or outcompete certain plant pathogens. But it has also been found that variability among formulations and preparation methods may yield inconsistent results and in some cases, dangerous growth of toxic microbes in compost teas. All of naturally derived pesticides are not used in green or organic farming. They are: nicotine sulphate, arsenic, and strychnine. Some synthetic pesticides used in eco-friendly farming are insecticidal soaps and horticultural oils for insect management and Bordeaux mixture, copper hydroxide and sodium bicarbonate in fungi management. But scientists also warn against their excessive use, as it can be more environmentally problematic than the use of many synthetic fungicides. Repeated application of copper sulphate or copper hydroxide as a fungicide may lead to copper accumulation to toxic levels in soil. So much so that in the European Union, replacement of copper-based fungicides in green or eco-farming is a policy priority.

As it has been mentioned above, the use of pesticides owes its origin in India mainly to the 1980s and the main crop for which it was used extensively was cotton. In the 1980s, the cotton crop witnessed repeated attack of American bollworm. Farmers started searching a way out and they made use of all sorts of pesticides. Farmers who grew cotton got so desperate that many of them ended their lives. In the 1970s, indigenous varieties were replaced with hybrid varieties. It was the time when major pesticide companies set up their factories in Punjab and started aggressive promotion campaign. Farmers made extensive use of pesticides and their cotton production touched newer heights. After cotton, farmers turned to other crops such as paddy, wheat and sugarcane. The use of pesticides thus became a trend.
Similarly, in Punjab and Haryana, farmers started using weedicides in the 1980s. Earlier, they used to remove weeds manually. In green, organic or eco-friendly farming, weed management involves weed suppression, rather than weed elimination. This is done by enhancing competition or phytotoxic effects on weeds. In green farming, cultural, biological, mechanical, physical and chemical tactics are integrated. Weed’s growth is stopped and impeded without synthetic herbicides. For green or organic farming, it is necessary that a single crop should not be grown in the same location without a different or intervening crop. Crop rotation provides weed-suppressive cover crops and crops with dissimilar life cycles to discourage weeds with a particular crop. Farmers increase soil organic matter content, which can support microorganisms that destroy common weed seeds. Weeds can also be controlled by grazing. For example, geese can be used successfully to weed a range of organic crops including cotton, strawberries, tobacco and corn. Rice farmers can introduce ducks and fish to wet paddy fields to eat both weeds and insects. Some naturally sourced chemicals are also used as weedicides. These include acetic acid (concentrated vinegar), corn gluten meal, and essential oils. Some selective bioherbicides have also been developed.
Soil management also plays a pivotal role in green farming. As we know, plants need nitrogen, phosphorus, and potassium as well as micronutrients and symbiotic relationships with fungi and other organisms to flourish, but getting enough nitrogen at the right time is a challenge for green farming. Crop rotation and green manure (cover crops) help to provide nitrogen through legumes which fix nitrogen from the atmosphere through symbiosis with rhizobial bacteria. Intercropping can increase soil nutrients substantially. Crop residues can be ploughed back into the soil, and different plants leave different amounts of nitrogqn, potentially aiding synchronisation. Green or organic farming involves use of animal manure, certain processed fertilisers such as seed meal and various mineral powders such as rock phosphate and greensand, a naturally occurring form of potash which provides potassium. Soil erosion can be controlled through these methods. Mixed farms with both livestock and crops can operate as ley farms, whereby the land gathers fertility through growing nitrogen-fixing forage grasses such as white clover or alfalfa and grows cash crops or cereals when fertility is established. Stockless farms or farms without livestock find it more difficult to maintain fertility, as they have to rely on external inputs such as imported manure as well as grain legumes and green manures. Biological research on soil and soil organisms has proved beneficial to green or organic farming. A number of bacteria and fungi break down chemicals, plant matter and animal waste into productive soil nutrients. Fields with little or no manure yield lower crops due to decreased soil microbe community providing healthier and more arable soil systems.
Sustainable farming, the ability of a farm to produce food indefinitely with little or no harm to its ecosystem, is catching on across the developed nations, Interest is driven by consumer demand for locally grown, organic and sustainable products. In fact, farmers have always been good managers of the land, but now they are being paid for it. Now, more and more farmers do not till their fields, after fall harvests. Leaving crop residue in place adds nutrients to soil and helps it retain moisture. Some farmers plant grasses that give nutrients, back to the soil. While rich farmers use inorganic methods to grow crops in Tndia, farmers with small holdings and marginal farmers are still mostly practising organic methods, passed down for millennia. Organic fertilisers and natural pest control measures are the only tools available to most of these farmers, who have always lacked the financial resources to explore chemical solutions. But these farmers, whose produce is as organic as they are supposed to be, cannot afford to pay the fees required to get official certification. As a result, they do not get the price for their produce they are entitled or supposed to get. On the other hand, eight chemicals were identified in the basmati rejected by the United States. Among these were traces of pesticides such as isoprothiolane, tricydazole and bavistan. India is an exporter of food-grain- related commodities worth Rs. 1 lakh crore per annum. Rice alone is exported to the tune of over 7 million tonnes (2011-12), including 3.2 million tonnes of basmati. The efforts being made by various institutions have failed to achieve desired goals. This has taken place despite the parameters fixed by the Food Safety and Standards Authority of India. As India is a very vast country, sustained campaign is needed and this calls for awareness on the part of every responsible and conscious citizen. Not that people have not realised the need of sustainable agriculture at all. The first Organic Food Mela of Delhi, which was organised jointly by “People For Animals” and The Indian’ Expresson December 16, 2012, bears testimony to the fact that people have started paying heed to the need of the hour, though not overwhelmingly.
We all know that agriculture is the provider of livelihood for nearly half of our working population. Studies done at the Indian Agricultural Research Institute indicate the possibility of the loss of 4-5 million tonnes in wheat production for every 1°C rise in temperature throughout the growing period. Losses for other crops are uncertain, but are expected to be smaller for the kharif crops. Agriculture sector contributes 18 percent of the total greenhouse gas (GHG) emissions from India. The emissions are primarily due to methane from the rice paddies, enteric fermentation in ruminant animals, and nitrous oxides from the application of manures and fertilisers. Although relative proportion of emissions from agriculture in India is likely to show considerable reduction in future because of the larger emissidn growth in other sectors, adaptation for agricultural communities will remain a major concern. The Twelfth Plan document clearly says that some policy and programmatic interventions can help farmers and other stakeholders adapt to climate change and reduce the losses. Change in cropping patterns, for example, can help adjustment to changes in mean temperature and precipitation. Amongst the key actions for adapting Indian agriculture to climate change are improved land management practices, development of resource conserving technologies, development of crop varieties that can withstand climate-stress, effective risk management through early warning, credit-insurance support to farmers and nutritional strategies for managing heat stress in dairy animals. Complementary actions in terms of identification of cost-effective opportunities for reducing methane generation, emissions in ruminants by modification of diet, and in rice paddies by water and nutrient management will help make adaptation measures sustainable. New policies should support the new land use arrangements, enhance investment in water harvesting, promote small-farm mechanisation and efficient water use technologies. A package of financial incentives for improved land management, including resource conservation (water, carbon, energy) and balanced fertiliser use may facilitate quicker adoption of these measures.

 

Inverse square law of illumination

By
Syskool
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Inverse square law of illumination :
The intensity of illumination of a surface by a point source of light varies directly with the illuminating power of the source and inversely as the square of the perpendicular distance from the source of the surface.
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Lenz’s law

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Lenz’s law :

When a circuit and a magnetic field move with respect to each other, the direction of the induced current is such so as to oppose the motion to which it is due.

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LAWS OF THERMO-DYNAMICS
First law of thermo-dynamics :
The heat produced in a mechanical work is in proportion to the work done.
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