Environment

Return of the Ice Age!

It was around 18000 years ago that the expansion of the Polar Ice Caps reached its peak and thereafter it began to contract. This was the end of the Pleistocene Ice Age globally. But in these past 18000 years there have been onslaughts of prolonged cooling in some parts of the world. For example, between AD 1300 and 1900 the Himalayan glaciers showed considerable advancement. These glaciers had begun to retreat after the warm phase had set in after the culmination of the Ice Age. The glacier in the Kedarnath Valley advanced so much that it kept buried the Temple for 400 long years.

Kedarnath Temple

Normally it is preposterous even to think of such a mishap for one of the most sacred temples of the Hindu faith. However, Kedarnath being in the shadow of glaciers and being above the snowline such a possibility can not be ruled out.

Kedarnath or ‘Lord of Kedar Khand’ is an ancient temple of Lord Shiva in Rudraprayag district of Uttarakhand. As the story goes no one knows when the temple came in to being. Everyone however, agrees that the Pandavas on their way to heaven performed penance at Kedarnath. A fact further corroborated by their statues in the first hall of the temple. The present temple was built by the Adi Shankaracharya in the 8th century AD at the site of an earlier temple built by the Pandavas, says a Garhwal Vikas Nigam pamphlet.

Well the purpose of this article is not to trace the history and origin of the Kedarnath, but to enlighten the readers with some interesting hitherto unknown facts about the snow cover around the temple. If the scientific findings have to be believed the temple was buried under the snow for 400 long years. 

Kedarnath falls within the regime of Chorabari Glacier. With the specter of global warming looming large, the glaciers have become a centre of attraction. It was this fact that drew R. K. Chaujar of Wadia Institute of Himalayan Geology, Dehradun to Kedarnath area. Being a Lichenometrist he used lichens as his source material for studying the advance and retreat of glaciers in the past. 

Lichens are peculiar organisms found almost everywhere and anywhere. They are result of an intimate association between an alga and fungus-two diverse organisms. Such an association is called a symbiotic relationship. They occur in some of the most extreme environments ranging from Arctic to hot Deserts. Many species of lichens are vulnerable to environment changes and are used by the scientists is assessing air pollution, ozone depletion and metal contamination. Lichens are used extensively by the researchers on glaciers for dating the advance and retreat of glaciers. The science of such studies is called Lichenometry.

Glaciers are an important aid for reconstructing the climate picture during the past 10000 years. Rocks, moraines etc of glaciated terrain are often covered with lichens. Their study of late has become quite a precise tool for studying the advance and retreat of glaciers. Glacier, unlike its massive and passive appearance is a great bulldozer in the nature. Its movement is usually imperceptible to naked eye, as it moves in millimeters or centimeters at best. But as it moves it pulverizes everything underneath to fine flour. The nature’s massive bulldozer not only pulverizes, it also carves typical glacial landforms. Which include broad U shaped valley. The sides of the glacier and its body contain huge boulders of country rock of sizes varying from almost a double storied building to a walnut. These are produced as they are wrenched from the parent rock mass by the eroding action of the glacier. 

There was a time when almost entire surface of the globe was covered with ice. Around 18000 years ago our planet saw the maximum spread of ice, known as the Quaternary Glacial Maxima. Thereafter set the warm cycle and the glaciers began to recede. As they receded they left their pile of moraines at different levels (altitudes). While the Ice Age or the cold phase of the earth changed to a warm phase in general, some local areas one again came in the grips of min-Ice Age in these 18000 years. Accordingly the glaciers advanced or retreated.

Chorabari glacier basin covers an area of 38 square kilometer. Actual glacier area is 15 sq km and it is six km long. A river has many tributaries, like wise a glacier has often hanging valleys as evidence of the connection with smaller glaciers. As the main glacier keeps on carving its valley deeper and deeper, over a period of several thousand years the smaller tributaries are left hanging at a higher elevation, hence the name hanging valley. 

Kedarnath temple is situated between two channels emerging out of two snouts of the Chorabari Glacier. The right snout situated at an altitude of 3865 meters above mean sea level is the present source of the Mandakini River. A stream also emerges from the left snout located at 3835 m asl and flows for a distance of about 100 m northwest of the Kedarnath temple and joins the mainstream from the right snout. In its prime there must have been only one glacier. But in the course of its retreat it was divided in to two parts with a snout for each. That is why the two streams. The mass of ice at the left snout appears to be thinner than the right one.

Panaromic View of Kedarnath Valley

The divider moraine also tells another story. At present it acts as the left lateral moraine of the main glacier and right lateral moraine of the tributary glacier. Both the main and the tributary glaciers have a common area where snow accumulates to feed them. It indicates that once upon a time there was a tributary glacier with a separate snow accumulation zone. Over a period of time due to retreat of glaciers the two have come close together to be separated by a common medial moraine. While the glaciers were retreating there was a period when once again they had advanced, which caused formation of a new lateral moraine-which is the present moraine. Thus the deserted rocky boulders of the glaciers have their own story to tell about the rich glorious past. The dimensions of the moraine formed later as a result of advancement before final retreat are much smaller, thus confirming the theory of another advancement of glacier, albeit for a shorter duration.

As a glacier advances it bulldozes chunks of rock material from the sides and while retreating they get deposited. Therefore their pattern and location helps the glaciologists to build a glacial history. Another significant feature of a glacier is scrapping of the surface on which it moves. The heavy ice mass laden with pulverized rock matter and smaller fragment acts like a giant sand paper, and its abrasive action scraps the surface. The striations thus produced are often preserved. It is well known that a glacier is a big carver of the landscape. More the ice on the glacier more is its carving capacity. The moraines of Chorabari glacier indicate that the later landforms carved by the glacier during the little Ice Age were of smaller dimension, while the earlier ones were also preserved. This was because the glacier did not have enough energy to wipe out the earlier landform and carve new one. On the other hand superimposition of smaller dimension moraines does confirm that glacial activity was in cycles and at one stage it had advanced once again.

Lichens grow on these moraines and with their help four stages of advance and retreat of Chorabari Glacier in the past have been worked out. Lichenometric study is based on a surmise that if the time taken by the lichen to grow on a surface after its exposure to the atmosphere and growth rate of lichens is known in an area, then a minimum date can be obtained by measuring maximum diameter of the largest diameter at the site. Though the method is said to be suitable for deposits up to 10000 years old, however, it is best efficient for dating deposits up to 500 years.

The exact date of the Kedarnath Temple is not known. From the historical records it can be safely taken as 3000 years old. It is intriguing that how could such a magnificent temple come up in such a glaciated terrain. Chaujar says that there could be three possibilities:

  • There was no glacier in the region at the time construction-minimum 3000 years ago.
  • There was a glacier but beyond the present location of the temple.
  • There was a glacier and the temple was constructed after cutting through the ice of the glacier at that particular position.

Two wall engravings with poems mentioning dates of AD 650 and 850 on the boundary wall behind the temple state the beauty of the place. But there is no mention of snow, ice or glacier around. It means there was no glacier at that period around the temple. In other words it means that there was no glacier around in 850AD.

The period between AD 1300 and 1900 is considered to be an era of worldwide glacial expansion and termed as the ‘Little Ice Age’. There was a worldwide glacial expansion during the ‘Little Ice Age’. 

Lichenometric dating in Kedarnath area has indicated that glaciations in the region started during the mid-14th century and continued till AD 1748. After its peak the Little Ice Age did not retreat in one go. Instead there were three major advances and retreats Evident from the moraine dumps left by the glaciers. With each advance the glaciers brought fresh moraines and left them behind with each retreat.

During this period nearly for 400 years the Kedarnath Temple must have remained buried under the ice. One has to marvel at he quality of construction. Those thick slabs of rock, chiseled to make the bricks withstood the onslaught of ice. The striated walls of the temple bear testimony to the moving ice under which they remained buried. Apart from striations the glacial scrubbing also gives a kind of polish or sheen to the rock surface. The inner walls of the temple reflect it too.

The narrative makes it amply clear that no point harping the bogey of global warming. Global warming is already there and it had started much before the advent of man on this earth. Yet there have been prolonged periods cooling as evidenced from the signs of snow cover over Kedarnath for 400 long years. These are natural phenomenon, controlled by forces much stronger than the man kind. Not only controlled but initiated and stopped by those forces alone. The human addition in the warming process is a minuscule of what the nature can do. 

But yes we should not forget to respect the nature and should not disrespect by polluting the atmosphere, hydrosphere or even the lithosphere.

14-Feb-2010

More by :  V. K. Joshi (Bijji)


Top | Environment

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