Global Warming and Climate Change: Myth or Reality?
Global warming and consequent changes in the climatic pattern across the geographies of the planet has been a hot topic in recent times across disciplines- natural and social sciences- supported by undue hype of popular media. Many scientists firmly believe global warming is hurting our environment. Even politicians and diplomats have become an integral part of the debate. Hence, global worming has acquired global significance and has found its place in the regional and global geo-politics. Former Secretary General of the United Nations, Kofi Annan emphasised at the ‘Climate Change Conference in Nairobi’ in November 2006 that climate change is not just an environmental problem, but also a health problem, a security problem and an economic problem for all nations. Today we have largely accepted that planet-wide environmental degradation is occurring and it is a serious concern for all of us.
Situation in the Himalaya
Since the mid-1970s the average air temperature measured at 49 stations of the Himalayan region rose by 1oC with high elevation sites warming the most (Hasnain 2000, WWF 2005). Studies in Nepal (Shrestha et al. 1999) and Tibetan Plateau (Liu et al. 2002) indicate the rising temperature in recent times, with the warming being consistent and continuous after the mid-1970s in Nepal. The average warming in Nepal in its annual temperature between 1977 and 1994 was found to be 0.06oC/year. Incidentally, in both the countries the rate of warming is found to be more pronounced in the high altitude regions than the lower ones. Similarly, the lowland areas of India do not show significant warming trend (WWF 2005) indicating that the Himalaya is more sensitive and affected by climate change. Similar analysis (Shrestha et al. 2000) on precipitation data, however, does not reveal any significant trends in Nepal.
Glacial retreat
One of the worst damages of global warming as revealed by various scientific studies has been the glacier retreat in the mountains and Glacial Lake outburst floods. While such phenomena have occurred due to geologic and geomorphic reasons in the past, scholars argue the rate and frequency of their occurrence have amplified severely in the last couple of decades, and sadly is increasing with time. Geoscientists have revealed a general shrinkage of mountain glaciers on a global scale and the trend was found to be more pronounced during the first half of the 20th century. After about 1950 mountain glaciers again started to grow. However, they again started to retreat with accelerating pace since the 1980s. Based on the scientific investigations, there have been forecasts that up to a quarter of the global mountain glacier mass could disappear by 2050 and up to half could be lost by 2100 (see WWF 2005). In the Himalayan region also glaciers have been found to be in a state of general retreat since 1850 (Mayewski and Jeschke 1979, WWF 2005).
In Nepal, the Khumbu glacier, a popular climbing route to the summit of Mt. Everest, has retreated over 5 km from where Sir Edmund Hillary and Tenzing Norgay set out to conquer Mt. Everest in 1953 according to research findings. Similarly, several other Nepali glaciers are fast retreating in recent decades (see among others Fujita et al. 1998, 2001, Kadota et al. 1997, Seko et al. 1998, WWF 2005). In India situation is no better. Recent scientific studies show that almost all the major Indian Himalayan glaciers are retreating at an increasing pace (see WWF 2005). Of particular importance is Gangotri glacier as it has attracted a massive media attention in recent years. Latest data in this connection shows that Gangotri is retreating at the rate of 23 m/yr. According to the recent research findings, since the last inventory of glaciers and glacial lakes in Bhutan by the International Centre for Integrated Mountain Development (ICIMOD) in 2001, 120 additional glacial lakes have formed in the mountains (Kuensel 2006: December 03), indicating a rapid pace of glacier retreat in Bhutan Himalaya. It also reveals us the fact that glacier retreat or advance is either caused by natural factors or global environmental changes and that local ecology has little control over it. This is so because Bhutan’s environment is relatively intact and the region still has over 64 per cent of its geographical area under forest.
Glacial Lake outburst flood
Glacial Lake Outburst Flood (GLOF) is primarily an outcome of glacial melting. They are catastrophic discharges of water resulting primarily from melting glaciers. According to WWF (2005), many of the big glaciers have melted and retreated rapidly and have given birth to the origin of a large number of glacier lakes. Due to the faster rate of ice and snow melting, caused by the global warming, the accumulation of water in these lakes has been increasing rapidly and resulting sudden discharge of large volumes of water and debris and causing flooding in the downstream. An accelerated retreat of the glaciers in recent times has led to an enlargement of several glacial lakes. As the glaciers retreat they leave a large void behind. The ponds occupy the depression earlier occupied by glacier ice. These dams are structurally weak and unstable and undergo constant changes due to slope failures, slumping, etc. and run the risk of causing GLOFs. Characterised by sudden releases of huge amounts of lake water, which in turn would rush down along the stream channel downstream in the form of dangerous flood waves, GLOF waves comprise water mixed with morainic materials and cause devastation for downstream riparian communities, hydropower stations and other infrastructure. Further, Glacial lake outburst flood (GLOF) causes disasters to life and property along the downstream, results serious death tolls and destroy valuable forests, and farms. In the long run, glacial retreat/melting and GLOFs tend to threaten regional environmental and human security.
Some of the worlds largest documented historical GLOFs occurred in Karakoram-Himalaya. The damming of upper Shyok River by chongkumdan glacier formed a lake. A sudden outburst from this lake occurred in 1929 and the flood wave traveled down the Shyok River into Indus creating a rise of 8 m, 740 km downstream from ice dam. In Nepal, thirteen GLOFs are observed since 1960 for 30 years duration giving a very high frequency of natural hazards (Yamada 1993, Bahadur 2004). GLOFs are poorly documented but observed to create floods raising water levels up to 100 m (Bahadur 2004). It is considered necessary to have scientific GLOF analysis for design flood of projects in glacier dominated watersheds.
While majority of the scholars link the retreat of glaciers and consequent GLOFs with the process of global warming, there are some scientists who do not agree with this theory. In this connection it would be informative to look into the observations made by Professor Jack D. Ives, a noted geomorphologist, communicated to this writer, in the context of Khumbu glaciers in Nepal Himalaya-
….it has been well documented that the Khumbu glaciers are thinning and retreating and that potentially hazardous glacial lakes are forming. At issue, however, is the degree of hazard, and this appears to have been grossly over-estimated. We must also ask how the occurrence of a natural event (ie jökulhlaup or glacial outburst floods) can be seen as “destroying the environment?” Jökulhlaup are known to have occurred in many glacierized mountain areas and have been documented in the Alps, Alaska, the Canadian Rockies, Karakoram, and Pamir, amongst others. In Iceland, where the actual term jökulhlaup originated, there is a reliable record of destruction of farms and villages extending over several hundred years. Thus, they are not specific to current global warming. So how can a natural process “destroy the environment?”
More significantly, what can anyone, or any institution, do to protect Mount Everest from global warming? The BBC News/South Asia (18 November 2004, online) cautioned that Mount Everest “could one day become nothing but rock,” implying that all its ice and snow would melt. That would require such a large increase in temperature that the entire population of the subcontinent (at least) would likely have died from heat prostration long before Mount Everest were stripped of its ice and snow. In other words, by the time the mountain had been reduced to a bare rock far more serious extra-Himalayan problems would have diverted attention.
Of more immediate concern, however, is that this form of over-dramatic activism runs the risk of substantial misrepresentation. It may also deflect from some of the actual problems facing the Sagarmatha National Park and World Heritage site. These include:
•Severe damage to the upper timberline belt vegetation and the alpine meadows by large numbers of trekkers and their porters;
•An excessive number of mountaineering expeditions permitted by the government;
•Inefficient park management too closely controlled from Kathmandu;
•Environmental damage perpetuated by the Nepalese military;
•The Maoist Insurgency;
•Over-dramatized reporting that may undermine the credibility of environmentalists.
Regardless of the above discussion, before any action is undertaken, the local people, the Sherpas, who have managed to survive quite successfully for several hundred years, need to be consulted. What are their views? How do they rank the problems, both environmental and socioeconomic, that they face? And can they advise all the many friends of the Khumbu worldwide if and how assistance can be provided?
According to Dr. Milap Chand Sharma of Jawaharlal Nehru University, who has done extensive research of glacial geomorphology in the Western Himalaya, “glaciers are the most sensitive parameters of temperature change, both positive and negative. However, global warming is not the reason of glacial retreat. It is a simple cyclic episode” (Down to Earth 2006, 15 December: 30). Further, against the conclusions of conventional geo-science, the recent finding of the scientists at England’s Newcastle University is bit different. According to their analysis of temperature trends in the western Himalaya over the past century, global warming could be causing some glaciers to grow (BBC News 2006: 24 August; The Australian 2006: 04 September). They found warmer winters and cooler summers, combined with heavier snow and rainfall could be causing some mountain glaciers to increase in size. The findings are significant, because temperature and rain and snow trends in the area impact on water availability for several million mountain population. Their research focussed on the Upper Indus Basin. The findings are published in the American Meteorological Society's Journal of Climate (ibid). It is also that, recent scientific study has found out that 106 new glaciers have formed in the mountains of Bhutan since the last inventory of glaciers and glacial lakes in Bhutan by the International Centre for Integrated Mountain Development (ICIMOD) in 2001 (Kuensel 2006:Decmber 3)
Discussion and Conclusion
Controversy kept aside, we cannot deny the fact that Himalayan glaciers are retreating at an increasing rate in recent times as shown by the majority of the scientific studies. Whether they are natural cyclic episode or result of global warming is not clear to us at this point of time. Further, we are also not confident if global warming, itself, is caused by human activities. The point here, however, is that both warming of Himalayan environment and the consequent melting of glacier pose serious threat to the security of the Himalaya and people living therein and its vicinity. Many of the smaller Mountain streams and natural springs are drying or have dried up. Crops in India have, in the last one-decade, failed so consistently that farmers are committing suicide.The solution to the problem is not so easy. Local steps like checking deforestation and overgrazing in the high altitude areas may not be sufficient enough to check glacial melting. In fact, this is a global problem and needs a global action. We, however, need to act in our own way to check global warming and at the same time keep in touch with other counterparts and see how they react to the problem. It is also that, all scientists associated with the geo-science should come together and work in close cooperation in the interdisciplinary problem of glacier variation with the aim of saving humanity from approaching disaster. Besides, accurate and timely information on the spatial locations and regular monitoring of the glacial lakes' behavior is needed, to supervise and check the GLOF hazards and also assess the damages to be occurred in the near future. Modern information tools such as Remote Sensing and GIS could play a lead role in identifying potential risk lakes and monitoring the GLOF events in near real time.
Select References
BBC News (2006), “Global warming boost to glaciers” August 24, [Online Web] Accessed 26 August 2006, URL: http://news.bbc.co.uk/2/hi/uk_news/england/tyne/5283278.stm
Liu, Shiyin, Lu Anxin, Ding Yongjian et al. (2002), “Glacier fluctuation and the inferred climatic changes in the A’nyemaqen mountains in the source area of the Yellow river, China”, Journal of Glaciology and Geocryology, 24 (6): 701-707
Penjore, U. (2006), “Glaciers are retreating”, kuensel, December 3, [Online: Web] Accessed 6 Decembr, URL: http://www.kuenselonline.com/modules.php?name=News&file=article&sid=7795
Shrestha, A.B., C.P.Wake, P.A. Mayeski and J.E. Dibb (1999), “Maximum temperature trends in the Himalaya and its vicinity: An analysis based on temperature records from Nepal for the period of 1971-97”, Journal of Climate, 12: 2775-2787
Shrestha, A.B., C.P.Wake, P.A. Mayeski and J.E. Dibb (2000), “Precipitation fluctuations in the Himalaya and its vicinity: An analysis based on temperature records from Nepal”, International Journal of Climate, 20: 317-327
WWF (2005), “An overview of glaciers, glacier retreat and subsequent impacts in Nepal, India and China”, Nepal Program: World Wide Fund for nature
Global warming and consequent changes in the climatic pattern across the geographies of the planet has been a hot topic in recent times across disciplines- natural and social sciences- supported by undue hype of popular media. Many scientists firmly believe global warming is hurting our environment. Even politicians and diplomats have become an integral part of the debate. Hence, global worming has acquired global significance and has found its place in the regional and global geo-politics. Former Secretary General of the United Nations, Kofi Annan emphasised at the ‘Climate Change Conference in Nairobi’ in November 2006 that climate change is not just an environmental problem, but also a health problem, a security problem and an economic problem for all nations. Today we have largely accepted that planet-wide environmental degradation is occurring and it is a serious concern for all of us.
Situation in the Himalaya
Since the mid-1970s the average air temperature measured at 49 stations of the Himalayan region rose by 1oC with high elevation sites warming the most (Hasnain 2000, WWF 2005). Studies in Nepal (Shrestha et al. 1999) and Tibetan Plateau (Liu et al. 2002) indicate the rising temperature in recent times, with the warming being consistent and continuous after the mid-1970s in Nepal. The average warming in Nepal in its annual temperature between 1977 and 1994 was found to be 0.06oC/year. Incidentally, in both the countries the rate of warming is found to be more pronounced in the high altitude regions than the lower ones. Similarly, the lowland areas of India do not show significant warming trend (WWF 2005) indicating that the Himalaya is more sensitive and affected by climate change. Similar analysis (Shrestha et al. 2000) on precipitation data, however, does not reveal any significant trends in Nepal.
Glacial retreat
One of the worst damages of global warming as revealed by various scientific studies has been the glacier retreat in the mountains and Glacial Lake outburst floods. While such phenomena have occurred due to geologic and geomorphic reasons in the past, scholars argue the rate and frequency of their occurrence have amplified severely in the last couple of decades, and sadly is increasing with time. Geoscientists have revealed a general shrinkage of mountain glaciers on a global scale and the trend was found to be more pronounced during the first half of the 20th century. After about 1950 mountain glaciers again started to grow. However, they again started to retreat with accelerating pace since the 1980s. Based on the scientific investigations, there have been forecasts that up to a quarter of the global mountain glacier mass could disappear by 2050 and up to half could be lost by 2100 (see WWF 2005). In the Himalayan region also glaciers have been found to be in a state of general retreat since 1850 (Mayewski and Jeschke 1979, WWF 2005).
In Nepal, the Khumbu glacier, a popular climbing route to the summit of Mt. Everest, has retreated over 5 km from where Sir Edmund Hillary and Tenzing Norgay set out to conquer Mt. Everest in 1953 according to research findings. Similarly, several other Nepali glaciers are fast retreating in recent decades (see among others Fujita et al. 1998, 2001, Kadota et al. 1997, Seko et al. 1998, WWF 2005). In India situation is no better. Recent scientific studies show that almost all the major Indian Himalayan glaciers are retreating at an increasing pace (see WWF 2005). Of particular importance is Gangotri glacier as it has attracted a massive media attention in recent years. Latest data in this connection shows that Gangotri is retreating at the rate of 23 m/yr. According to the recent research findings, since the last inventory of glaciers and glacial lakes in Bhutan by the International Centre for Integrated Mountain Development (ICIMOD) in 2001, 120 additional glacial lakes have formed in the mountains (Kuensel 2006: December 03), indicating a rapid pace of glacier retreat in Bhutan Himalaya. It also reveals us the fact that glacier retreat or advance is either caused by natural factors or global environmental changes and that local ecology has little control over it. This is so because Bhutan’s environment is relatively intact and the region still has over 64 per cent of its geographical area under forest.
Glacial Lake outburst flood
Glacial Lake Outburst Flood (GLOF) is primarily an outcome of glacial melting. They are catastrophic discharges of water resulting primarily from melting glaciers. According to WWF (2005), many of the big glaciers have melted and retreated rapidly and have given birth to the origin of a large number of glacier lakes. Due to the faster rate of ice and snow melting, caused by the global warming, the accumulation of water in these lakes has been increasing rapidly and resulting sudden discharge of large volumes of water and debris and causing flooding in the downstream. An accelerated retreat of the glaciers in recent times has led to an enlargement of several glacial lakes. As the glaciers retreat they leave a large void behind. The ponds occupy the depression earlier occupied by glacier ice. These dams are structurally weak and unstable and undergo constant changes due to slope failures, slumping, etc. and run the risk of causing GLOFs. Characterised by sudden releases of huge amounts of lake water, which in turn would rush down along the stream channel downstream in the form of dangerous flood waves, GLOF waves comprise water mixed with morainic materials and cause devastation for downstream riparian communities, hydropower stations and other infrastructure. Further, Glacial lake outburst flood (GLOF) causes disasters to life and property along the downstream, results serious death tolls and destroy valuable forests, and farms. In the long run, glacial retreat/melting and GLOFs tend to threaten regional environmental and human security.
Some of the worlds largest documented historical GLOFs occurred in Karakoram-Himalaya. The damming of upper Shyok River by chongkumdan glacier formed a lake. A sudden outburst from this lake occurred in 1929 and the flood wave traveled down the Shyok River into Indus creating a rise of 8 m, 740 km downstream from ice dam. In Nepal, thirteen GLOFs are observed since 1960 for 30 years duration giving a very high frequency of natural hazards (Yamada 1993, Bahadur 2004). GLOFs are poorly documented but observed to create floods raising water levels up to 100 m (Bahadur 2004). It is considered necessary to have scientific GLOF analysis for design flood of projects in glacier dominated watersheds.
While majority of the scholars link the retreat of glaciers and consequent GLOFs with the process of global warming, there are some scientists who do not agree with this theory. In this connection it would be informative to look into the observations made by Professor Jack D. Ives, a noted geomorphologist, communicated to this writer, in the context of Khumbu glaciers in Nepal Himalaya-
….it has been well documented that the Khumbu glaciers are thinning and retreating and that potentially hazardous glacial lakes are forming. At issue, however, is the degree of hazard, and this appears to have been grossly over-estimated. We must also ask how the occurrence of a natural event (ie jökulhlaup or glacial outburst floods) can be seen as “destroying the environment?” Jökulhlaup are known to have occurred in many glacierized mountain areas and have been documented in the Alps, Alaska, the Canadian Rockies, Karakoram, and Pamir, amongst others. In Iceland, where the actual term jökulhlaup originated, there is a reliable record of destruction of farms and villages extending over several hundred years. Thus, they are not specific to current global warming. So how can a natural process “destroy the environment?”
More significantly, what can anyone, or any institution, do to protect Mount Everest from global warming? The BBC News/South Asia (18 November 2004, online) cautioned that Mount Everest “could one day become nothing but rock,” implying that all its ice and snow would melt. That would require such a large increase in temperature that the entire population of the subcontinent (at least) would likely have died from heat prostration long before Mount Everest were stripped of its ice and snow. In other words, by the time the mountain had been reduced to a bare rock far more serious extra-Himalayan problems would have diverted attention.
Of more immediate concern, however, is that this form of over-dramatic activism runs the risk of substantial misrepresentation. It may also deflect from some of the actual problems facing the Sagarmatha National Park and World Heritage site. These include:
•Severe damage to the upper timberline belt vegetation and the alpine meadows by large numbers of trekkers and their porters;
•An excessive number of mountaineering expeditions permitted by the government;
•Inefficient park management too closely controlled from Kathmandu;
•Environmental damage perpetuated by the Nepalese military;
•The Maoist Insurgency;
•Over-dramatized reporting that may undermine the credibility of environmentalists.
Regardless of the above discussion, before any action is undertaken, the local people, the Sherpas, who have managed to survive quite successfully for several hundred years, need to be consulted. What are their views? How do they rank the problems, both environmental and socioeconomic, that they face? And can they advise all the many friends of the Khumbu worldwide if and how assistance can be provided?
According to Dr. Milap Chand Sharma of Jawaharlal Nehru University, who has done extensive research of glacial geomorphology in the Western Himalaya, “glaciers are the most sensitive parameters of temperature change, both positive and negative. However, global warming is not the reason of glacial retreat. It is a simple cyclic episode” (Down to Earth 2006, 15 December: 30). Further, against the conclusions of conventional geo-science, the recent finding of the scientists at England’s Newcastle University is bit different. According to their analysis of temperature trends in the western Himalaya over the past century, global warming could be causing some glaciers to grow (BBC News 2006: 24 August; The Australian 2006: 04 September). They found warmer winters and cooler summers, combined with heavier snow and rainfall could be causing some mountain glaciers to increase in size. The findings are significant, because temperature and rain and snow trends in the area impact on water availability for several million mountain population. Their research focussed on the Upper Indus Basin. The findings are published in the American Meteorological Society's Journal of Climate (ibid). It is also that, recent scientific study has found out that 106 new glaciers have formed in the mountains of Bhutan since the last inventory of glaciers and glacial lakes in Bhutan by the International Centre for Integrated Mountain Development (ICIMOD) in 2001 (Kuensel 2006:Decmber 3)
Discussion and Conclusion
Controversy kept aside, we cannot deny the fact that Himalayan glaciers are retreating at an increasing rate in recent times as shown by the majority of the scientific studies. Whether they are natural cyclic episode or result of global warming is not clear to us at this point of time. Further, we are also not confident if global warming, itself, is caused by human activities. The point here, however, is that both warming of Himalayan environment and the consequent melting of glacier pose serious threat to the security of the Himalaya and people living therein and its vicinity. Many of the smaller Mountain streams and natural springs are drying or have dried up. Crops in India have, in the last one-decade, failed so consistently that farmers are committing suicide.The solution to the problem is not so easy. Local steps like checking deforestation and overgrazing in the high altitude areas may not be sufficient enough to check glacial melting. In fact, this is a global problem and needs a global action. We, however, need to act in our own way to check global warming and at the same time keep in touch with other counterparts and see how they react to the problem. It is also that, all scientists associated with the geo-science should come together and work in close cooperation in the interdisciplinary problem of glacier variation with the aim of saving humanity from approaching disaster. Besides, accurate and timely information on the spatial locations and regular monitoring of the glacial lakes' behavior is needed, to supervise and check the GLOF hazards and also assess the damages to be occurred in the near future. Modern information tools such as Remote Sensing and GIS could play a lead role in identifying potential risk lakes and monitoring the GLOF events in near real time.
Select References
BBC News (2006), “Global warming boost to glaciers” August 24, [Online Web] Accessed 26 August 2006, URL: http://news.bbc.co.uk/2/hi/uk_news/england/tyne/5283278.stm
Liu, Shiyin, Lu Anxin, Ding Yongjian et al. (2002), “Glacier fluctuation and the inferred climatic changes in the A’nyemaqen mountains in the source area of the Yellow river, China”, Journal of Glaciology and Geocryology, 24 (6): 701-707
Penjore, U. (2006), “Glaciers are retreating”, kuensel, December 3, [Online: Web] Accessed 6 Decembr, URL: http://www.kuenselonline.com/modules.php?name=News&file=article&sid=7795
Shrestha, A.B., C.P.Wake, P.A. Mayeski and J.E. Dibb (1999), “Maximum temperature trends in the Himalaya and its vicinity: An analysis based on temperature records from Nepal for the period of 1971-97”, Journal of Climate, 12: 2775-2787
Shrestha, A.B., C.P.Wake, P.A. Mayeski and J.E. Dibb (2000), “Precipitation fluctuations in the Himalaya and its vicinity: An analysis based on temperature records from Nepal”, International Journal of Climate, 20: 317-327
WWF (2005), “An overview of glaciers, glacier retreat and subsequent impacts in Nepal, India and China”, Nepal Program: World Wide Fund for nature
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