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Here is a term paper on ‘Climate Change and Himalayan Glaciers’ for class 8, 9, 10, 11 and 12. Find paragraphs, long and short essays on ‘Climate Change and Himalayan Glaciers’ especially written for school and college students.
Term Paper # 1. Introduction to Climate Change:
The mankind has entered the 21st century in the midst of social, economic, developmental and environmental challenges that need to be addressed at a global scale. One of the most important issues confronting the planet is undoubtedly the threat of global warming and the most prominent indicators of climate change is the melting of ice mass and glaciers worldwide. Over the last few decades, changes in climate and local weather conditions have impacted the world’s glaciers both in terms of structure and characteristics, reflected in the form of advancement or retreat of glacial snouts (UNEP, 2007).
The changes in the length, width, area, volume and mass balance of the glaciers are among the most directly visible signals of global warming and these changes are the primary reasons why glacial observations have been used for climate system monitoring for many years, especially in areas where time series data on climate (mainly temperature and precipitation) is difficult to get and where climate change signals are not yet clear.
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Unnatural rates of glacial melting can have serious implications on the hydrology of the associated river systems and consequently on the livelihood of millions of people who are dependent on these rivers and their ecosystems. Warming has caused the snowline in the Himalayas to shift upwards, thus indicating an increase in the ablation area of the glaciers. This receding phenomenon has gathered pace in the past few years.
Recent studies from 466 glaciers of the Indian Himalayas indicate that there has been a 21 per cent reduction in the glacierised area-from 2,077 sq km in 1962 to 1,628 sq km in 2004. Smaller glaciers of less than one sq km have reduced in area by as much as 38 per cent compared to a 12 per cent retreat of the larger glaciers. The melting process has two key adverse impacts on the environment. One is the loss in the reserve of freshwater and the other is a significant rise in sea levels.
These ecosystems have an intricate web of interaction and therefore changes in any one of their components can have a chain of impacts on the other elements. The right approach, thus, in addressing these impacts is to have a better scientific understanding through long-term observations and analysis of the interactions of the different components of the mountain ecosystems with their climate, and then utilise this information to formulate effective adaptation and management strategies.
Term Paper # 2. Himalayan Glaciers – An Overview:
The Himalayas, the youngest and one of the most fragile mountain systems in the world, derive their name from a Sanskrit word, which means ‘abode of snow’. The mountain ranges of the Himalayas stretch for a distance of about 2,400 km in an east-west direction in the shape of an arc along the northern border of India covering an area of about 500,000 km2.
The Himalayas have three parallel running series of mountains – the greater Himalayas or the Himadri range, which has some of the highest peaks of the world; the middle Himalayas or Himachal and the lower Himalayas or the Shivalik range. Plateaus and flat bottom valleys of thick gravel and alluvium are found in between the Himachal and Shivalik ranges.
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The Himalayas comprise approximately 33,000 sq km of glacierised area and its glaciers are a source of ten of the largest rivers in Asia. The rivers flow trans-boundary and meet the drinking water, irrigation, hydropower, fishery, inland navigation and other needs of more than 1.3 billion people living downstream. With about 9,575 small and large glaciers in the Himalayas, they hold the largest reserves of water in the form of ice and snow outside the Polar Regions. The Himalayas are thus also referred to as the ‘water towers’ of Asia and a ‘third pole’ of the earth.
The glaciers of the Indian Himalayas are spread over different river basins including the Indus, Ganga and Brahmaputra. Inventories of the Himalayan glaciers by the Geological Survey of India (GSI) indicate that the Bhagirathi sub-basin has the largest glacierised area of about 755 sq km with as many as 238 glaciers including the Gangotri glacier (26-30 km).
In comparison, the Brahmaputra basin has nearly 161 glaciers although it occupies a much smaller glacierised area of about 223 sq km Some of the other important glaciers found in the Himalayas include Siachen (72 km), Zemu (26 km), Milam (19 km), Kedarnath (14.5 km) and Dokriani (5.5 km).
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The existence of the glaciers in the Himalaya is due to their orographic characteristics (high altitudes exceeding above 0°C isotherms) and local and regional climatic conditions. In addition to these, the Himalayas are influenced by both the Indian summer monsoon and the westerlies, though not homogeneously. Some of the Himalayan glaciers are nourished only by the Indian summer monsoon (in summer) when accumulation and ablation is concurrently taking place while some other glaciers are nurtured only by the westerlies (in winter) during the accumulation period.
A few glaciers are nourished by both the monsoon and the westerlies. The dynamic monsoon system in turn is also influenced by the complex orographic characteristics of the Himalayas, coupled with snow and glacial environments. The radiation balance due to snow/ice cover provides feedback mechanisms for advection of water vapour from the surrounding oceans and maintains the seasonal cycles of monsoon.
The Himalayas also play a critical role in the tropical summer monsoon climate in the Indian sub-continent by functioning as an effective meteorological barrier. They obstruct the advancement of the monsoon towards the north, thereby resulting in more rainfall on the southern slopes.
Term Paper # 3. Himalayan Glaciers – Understanding Changes:
The freshwater melt from the glacierised basins is a vital element in regulating the dry season flows of perennial Himalayan river systems. Being closer to the Tropic of Cancer, the Himalayan glaciers receive more heat than the arctic and temperate climate mountain glaciers, and hence they are very sensitive to the rising temperature or climate variability both at regional and global levels. The responses of various glaciers are different due to variations in mass balance and the climate change impacts they face. Both a short-term perturbation in inputs as well as a long-term change in precipitation are said to affect glacial retreat.
Some of the studies carried out in the Indian Himalayas clearly point out an increase in glacial melt. For instance, the Baspa basin of Himachal Pradesh has shown an increase in the winter stream flow by 75 per cent as compared to the rate in 1966. This is in tandem with the rise in average winter temperatures in the area, possibly illustrating the impacts of global warming in the form of increased snow ablation, which in turn has augmented the stream flow.
Climate change impacts are also visible in the mass balance study of the Chhota Shigri glacier in the Chandra valley of Himachal Pradesh. The study shows that there has been a decrease in the Accumulation Area Ratio (AAR) of the glacier and it has had a negative mass balance in the years 2002- 2005.
Thus, climatic variability and growing impacts of climate change is posing pressure on our natural water supply. A holistic approach is required to manage the freshwater resources in the Himalayas and ensure environmental security in the region. For this, knowledge of glacial melt characteristics and their subsequent impacts on freshwater availability is essential. However, the current knowledge about the behaviour of glaciers in the Himalayan region is still limited.
Term Paper # 4. Glacier Retreat in the Himalayas:
In the Himalayan region, glaciers and snow cover have been thinning since the end of 19th century in line with the global trends. With significant snout fluctuations, most of the glaciers in the Himalayan mountain ranges have been retreating at accelerated rates in the last three decades (WWF, 2005) and their rate of retreat is much faster than that of glaciers in other parts of the world. These changes correspond to the rising surface temperature trends in the Himalayas, which have been reported to be higher than the global average warming.
A study of the temperature trends in the northwest Himalayan region shows that a significant warming of 1.6°C has occurred over the last century with warming in winter taking place at a faster rate, with the highest warming rates recorded in the period 1991-2002. This warming has been due to a rise in both maximum and minimum temperatures, though the maximum temperature have gone up more rapidly.
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Apart from warming, other factors like high human population density near these glaciers, deforestation and land use changes have also been responsible for the decline and shrinkage of glaciers. At current rates of retreat, the smaller valley type glaciers are more likely to decline at a faster rate in the future, with uncertain impacts on the downstream areas.
In India, although high mountain glaciers occur across all the Himalayan range states of Jammu and Kashmir, Himachal Pradesh, Uttarakhand, Sikkim and Arunachal Pradesh, only a few have been studied for long term monitoring or documented in terms of glacial retreat. The climatology and the topography of the Himalayan region have wide variations all across the arc.
Owing to these variations different parts of this region have been exhibiting diverse responses to the variability in climate. Singh and Bengtsson (2005) found that under a warmer climate, the melting from the seasonally snow covered part of the basin was reduced while, in contrast, it increased from the glacier-fed basin.
The dynamics of a glacier are influenced by climatic factors including temperature, precipitation, amount of snowfall and wind. In the Indian Himalayas, studies on snout recession/mass balance measurements have been carried out on a few glaciers and some studies have been able to generate long-term monitoring data. While studies by various institutions on the changing characteristics of glaciers in the Himalayas may be limited, this has generated an important debate on the role of climate change in the extent of glacier loss.
While the global view (IPCC, 2007) suggests that a large percentage of glaciers are declining worldwide, there are conflicting views also on the rate of retreat in the postindustrial era. Some studies suggest that a few glaciers in the Himalayas may be showing reduced retreat patterns. For instance, the reduction in the retreat rate of Gangotri glacier for 2004-05 was obtained by Kumar et al (2007).
Similar results have been observed on the Gangotri glacier, which shows that the average rate of retreat for this glacier declined substantially (6.02 m/yr) during 1999 to 2006. On the basis of several observations, it can be said that the effects of climate change have variable impacts on glaciers depending on their size. Small glaciers are more likely to face the brunt of the changes in climate owing to their smaller accumulation zones. On the other hand large glaciers might sustain the impacts for a longer time due to their larger ice volume and bigger accumulation zone.
WWF-India has been raising awareness about climate change and the impacts on Himalayan ecosystem since 2005. In order to generate a deeper understanding of the potential impacts of glacial melt in the Himalayas, WWF initiated a project in 2006, which focused on studying two key glaciers from a climate change perspective and the subsequent impacts on freshwater availability.
These glaciers were the 30 km long Gangotri glacier and the 4.2 km long Kafni glacier, both located in the state of Uttarakhand. This would help in developing regional climate projection models which are more accurate in providing information on future impacts.