Raphstreng – Thorthormi barrier

Excessive melting continuing in Thorthormi but other Glaciers also losing mass for years

According the National Center for Hydrology and Meteorology (NCHM) a recent field trip to Thorthormi lake in October 2020 showed that the Glacial Lake Outburst Flood (GLOF) hazard is still high as excessive melting continued on the Thorthormi glacier.

The 2020 survey looked at the Raphstreng lake and Thorthormi barrier and also the lake outlet of Thorthormi.

In June 2019 Bhutan got a fright when a large volume of water suddenly rushed out of the Thorthormi lake impacting the lake outlet and prompting fears of a GLOF.

What had happened was that unusually high temperatures and a delayed monsoon along with long term climate change led to excessive melting and so a section of the glacier surged into the lake raising its level by several meters.

The result was a large volume of water flowing out to the point that subsidiary lake 2 was completely eroded away.

The 2020 survey found that the Raphstreng lake and Thorthormi barrier is 33.3 meters at the narrowest crest and sliding on either sides is continuing.

The lake outlet did not see any major changes between 2019 and 2020.

The NCHM recommends the annual monitoring to continue and to check for the stability of the moraine wall between the two lakes.

At the larger level, Bhutan’s glaciers have been constantly loosing mass for consecutive years over the last decade or two.

Director Karma Dupchu, NCHM said that the temperature has been a direct factor in the lead up to these glaciers melting.

Karma, Chief/Specialist, Cryosphere Services Division said, “When we talk about glaciers, usually people talk about the hazardous part of it, for example Thorthormi glacier- many people know about it, but if we talk about Thana glacier or others, people don’t realize the importance of glaciers to Bhutan.”

He stated that the center’s primary focus is in long-term monitoring for 2 glaciers which have been identified as benchmark glaciers namely; Gangju la and Thana glacier.

 The report from surveys carried out between 2004 to 2020, highlighted that Gangju La Glacier which is Located at the Pho Chu Sub-basin has shrunk by 27.6 % of its initial Surface area.

Over the years, it was reported to have lost 28.5 ton of water from the glacier.

 The glacier had a total terminus retreat from 2004 to 2020, retreating back by 182 meters at an average rate of 11.4 m per year.

 Similarly, the other benchmarked glacier, Thana Glacier located at Chamkhar Chu Sub-basin showed that over the years the glacier has lost a total cumulative mass of 5.98 ton of glacial water in between 2017 and 2020.

The initial survey for Thana glacier was conducted in the year 2013. The glacier has lost glacier mass equivalent to 2.784 ton of glacial water loss from 2019-20. 

As per the Bhutan Glacier Inventory (BGI) report of 2018 there are over 700 glaciers covering 1.64% of total land in the country.

Highest number of glaciers was identified at Pho Chhu sub basin with area coverage of 252.42 km, with over 206 glaciers in the region.

 Karma said that glaciers are important indicator of climate change and climate change being one of the worries for the world other than COVID-19 should also be monitored in a timely manner and be considered as an important matter.

Reportedly, the center continues to study the 3 fundamental importances of glaciers namely; as a climate indicator, on glaciers being the fresh and usable water reservoir and in assessing the natural hazards that are associated with it.

 The Director stated that as per the requirement of activities and various procedural routes in the field of the center’s work, working as a Department is not technically suited and that as per the current practice, there are no proper government policies to efficiently facilitate the services.

He added that if the center was autonomous instead, some of these challenges would be curbed.

Message from The Bhutanese

Dear Reader,

Advertise with The Bhutanese for your money’s worth

Whether you are a government agency or a private business, the COVID-19 Pandemic and its economic impact means every Ngultrum counts when you want to advertise a tender, vacancy, public notification or your business.

Advertise with The Bhutanese which is the only newspaper in Bhutan that reaches all 20 Dzongkhags according to a 2019 BICMA Circulation Audit.

Apart from being widely read we also place your advertisements in our popular Facebook and Twitter pages which have more followers than all other private media combined.

Our rates are far more reasonable than those of state owned media outlets.

Contact us at: Mb Nos 77351243, 17231307, 17255501 (At all hours and holidays)

Landline: 335605 Fax: 02 335593 (9 am to 5 pm)

Email: ad.bhutanese@gmail.com (At all hours and holidays)

Check Also

Gyalyum Sangay Choden Wangchuck honored with Award

Her Majesty Gyalyum Sangay Choden Wangchuck has been awarded as the individual laureate for the …

Leave a Reply

Your email address will not be published. Required fields are marked *