By Rehmat Ali
Solid crystalline material in Shishper is deforming and moving 7m per day towards Hassanabad village. This process has been going on for three months. The expanding glacier has dammed the glacial stream, and formed a surging lake. The water accumulated in the ‘lake’ is less, because the temperature is low. Come spring, and the accelerated glacial melt with add more to the volume of the lake. This can cause floods, which can affect human settlements, including a portion of the Karakoram Highway.
Hassanabad village is facing a two major disasters at the same time: 1) the expanding glacier may reach the village, and 2) there might be a massive flood.
While the government and AKAH are taking appropriate precauationary measures, these incidents call for greater understanding of ‘glacial behavior’, because our region is highly glaciated, and this incident can also occur somewhere else.
Mass balancing are the the fundamentals of a glacier, advancing or retreats. The sheer weight of a thick layer of ice or the force of gravity on ice mass can causes a glacier to move. Ice is soft and more easily deformed by pressure; movement along the underside of a glacier is slower than movement at the top due to friction
Glaciers may race forward several meters per day for weeks or even months. The fastest a glacier has been observed to advance is 30 meters per day, and the slowest is 1m per year.
The Kutiah Glacier in Pakistan holds the record for the fastest glacial surge; in 1953 it raced more than 12m Per day, averaging 36 feet per day. Such movements have important role in sculpting many landscapes
There are four processes linked in glacial advancing, and all are driven by gravity.
Basal Sliding : The entire glacier slides over its beds; enhanced if the bed is soft sediment, if the glacier bed is thawed, and melt water is prevalent.
Bed Deformation: This is limited to the area of slide, seasonal melting, ponding, glacier shows seasonal acceleration and deceleration of ice flows are some of its features.
Glacial Quakes : A jolt that is sufficient to generate moderate seismic waves; this can move 10 meters in less than a minute.
Internal Deformation : This occurs when the weight of the ice crystalline cause the deformation of ice crystal near the glacier bed where pressure are highest. Glacial crystala can grow to be as large as baseball’s.
It is important to educate the masses about glacial movements, and other geological phenomena. This can help the locals in deciding whether they can invest heavily in areas near glaciers, or not. It can also help save lives and properties.
Schools, colleges and universities can play an important role in advancing scientific knowledge. Our region is a geological wonderland. Instead of learning from it, and living intelligently, we try to jump to action when a lot has already happened. This needs to change.
The contributor is a graduate of Earth Sciences. He is a Glaciology enthusiast.
* Facts taken from National Snow and Ice Data Center.