Avalanche threat: Real or hoax

While it is still a long way for the costal areas to recover from Tauktae, and Yaas cyclones that hit western, and eastern coast of India in quick succession,  possibility of an avalanche has been expressed by some vernacular newspapers in the Himalayan state of Uttarakhand. And believe me, this avalanche threat is not based on an avalanche warning by some scientific institution. This is in fact a wild correlation done by the media.

Its true that Uttarakhand has witnessed two avalanche incidences in quick succession; on February 7, 2021 in the upper reaches of Rishiganga catchment, and on April 23, 2021 in the catchment of Dhauliganga river. Based on pre-disaster satellite imageries of the area scientists have come up with evidences that show appearance of fractures in the glacial mass well before February 7, 2021 incidence. Yes, these have been put forth as  precursors, but no scientific study done anywhere in the world suggests that every fracture on the glacial mass would be followed by an avalanche. In such a situation this sensational report is a big question mark on the judiciousness of the media.

Those of you who follow disaster incidences would be aware that Rishiganga, and Dhauliganga valleys of Uttarakhand were devastated by a major flood event recently on February 7, 2021. 204 persons were killed while two hydropower projects located in close proximity at Rishiganga (13.2 MW), and Tapoban (520 MW) were damaged in this incidence.

Rather than devastation what surprised both masses, and the scientists alike relates to basic facts that (i) the this flood event took place during winter season when the discharge of glacier fed rivers is minimal, (ii) this flood was not accompanied by rainfall in the catchment, and (iii) there was no glacial / landslide lake outburst event in the catchment.

There is still lack of consensus amongst scientists on the causes of this flood even though all agree that the flood was preceded by break up, and fall of a portion of a major hanging glacier of the Nanda Devi massif.

Those of you who know the area well, would be aware that around this part of the year there is a rush of local inhabitants towards higher glaciated reaches in search of what is popularly known as Keera Jari. You might recognize it as caterpillar fungus (Ophiocordyceps sinensis), or Yartsagunbu (in Tibetan). It is famous for its use in traditional Asian medicine, and often sells at prices higher than its weight in gold. So it is the time of gold rush in the Himalayas.

Amid this quest some enthusiastic youngsters shot random videos, and photographs of the area from where initiated the avalanche of February 7, 2021 that resulted in devastating flood in the downstream areas.

Based on the video it is hard to assess the threat of any kind, and there is nothing unusual if crevasses have been observed in the glacial mass. These are common geomorphic features associated with glaciers, and are related to glacier dynamics.

But out here these have been correlated, interestingly by the media, with the cracks observed on pre-February 7, 2021 satellite imageries that were widely publicised by scientists, and put forth as precursory evidence of the associated avalanche activity. So the possibility of yet another avalanche, and ensuing flood has been put forth.

Such reports generally go viral, and masses get to know of these quite early compared to the warnings disseminated by the state. With memories of the devastating flood still fresh, there thus seems nothing wrong in panic.

The media has already sensationalised the issue, and the masses are naturally under panic. The state is thus under pressure to get the issue investigated scientifically, and assess the threat, if any.

But then such investigations have their own limitations; (i) area cannot be assessed physically because of constraints related to weather, and terrain, (ii) aerial reconnaissance is what can best be resorted to, and (iii) visibility and weather would determine the details that can be observed. Moreover slope instability is a tricky affair, and even after detailed field investigations one can express it only in terms of probability of the mass coming down, and one certainly cannot negate changes of the incidence taking place. Moreover, no one can really tell in advance the time when the mass is to come down.

In such a situation it would not be easy for the state to rule out the threat outright, even with support, and cooperation of the scientists. In such a situation it would be hard to convince the masses, and the panic aroused by media would only subside with the passage of time.

It is therefore required that priority be given by media to substantiating facts by scientific opinion, rather than trying to sensationalise the issue, and yield to the pressure of breaking news.