Constructions added to climate crisis woes

Hindustan Times

4 days ago

The series of suspected cloudbursts that hit three locations near Harsil, a village between Uttarkashi and Gagotri in Uttarakhand, was triggered by the monsoon trough being more north than it usually is at this time of the year, and accentuated by a cyclonic system over Bihar. according to experts. Glaciers are melting and the debris from the glaciers are flowing with the river water. (PTI photo)
According to Uttarkashi district administration, at least 20 people are missing and about 80-90 buildings have been damaged as a result of the extreme weather events, likely caused by the climate crisis, and exacerbated by untrammelled construction in the region, including in river beds and on fragile slopes.
A status note on Tuesday evening by the Central Water Commission said a series of extreme weather events in the form of suspected cloudbursts occurred in quick succession on Tuesday in the Uttarkashi district, causing widespread damage and potential casualties. The first incident took place in Dharali, near Harshil, around 1:00 pm. The second incident occurred between Harshil and Gangnani (near Sukki Top), around 3:00 pm. And the third incident occurred near Army Camp, Harshil, around 3:30 pm
Horrifying videos of multiple buildings, habitations, market areas being washed away in the Bhagirathi Ecosensitive Zone, has once again captured the impact of climate change in the upper reaches of the Western Himalayas. But the experts also said that the impact has been particularly devastating because of the number of constructions on what appears to be the riverbed of Khir Ganga, a tributary of Bhagirathi.
Heavy rain, or cloudburst?
India Meteorological Department officials said there was no way to confirm if the extreme weather events were 'cloudbursts'.
Cloudbursts are very localised phenomena that result in rain of 100mm in an hour.
'There has been extremely heavy rainfall, over 300 mm in parts of Uttarakhand in the past 24 hours. As you can see from the video, extremely heavy rain may have occurred in very high reaches. We have no way to monitor if it was in fact a cloudburst as there are no stations in very high altitude areas. But we know that there was extremely heavy rain,' said M Mohapatra, director general, IMD.
'The monsoon trough has been to the north of its normal position for the past three days causing concentrated, heavy rain only over the Himalayan foothills. When such continued rainfall occurs, in certain areas the soil saturates and water overflows. The water is seen flowing downstream. There is also a cyclonic circulation over Bihar and surrounding regions, accentuating the impact,' he added.
The frequency of such events has been increasing. There has been a rise in short span high intensity rain occurrences (mini cloudbursts) along the west coast of India and along the foothills of Western Himalayas between 1969 and 2015 according to 'Assessment of Climate Change over the Indian Region,' a report by the union ministry of earth sciences published in 2020.
'There is clear evidence that extreme precipitation has increased everywhere including these hilly states. This is a clear signal of global warming. This heavy rain and flash flood is not unexpected. The number of cloudbursts is most certainly going up in the hilly states,' said M Rajeevan, former secretary, ministry of earth sciences and climate scientist.
Scientists have also said even if heavy rainfall events do not meet the exact criteria defined, but cause extensive damage such as flash floods and landslides in high altitude areas, they should also be considered cloudbursts.
'The Himalayan region is experiencing higher warming than the global mean. This is known as elevated warming. This can increase cloudbursts, as under warm condition water holding capacity of air increases and strong upward movement of air due to slope increases moisture in the air column.This leads to a cloudburst in mountainous terrain,' said Anil Kulkarni, distinguished visiting scientist, Divecha Center for Climate Change, Indian Institute of Science.
'Since 2018 we are seeing a major escalation in extreme weather events and associated disasters. Even before the Kedarnath disaster in 2013, there were two major cloudbursts in Assi Ganga and Ukhimath. But after 2018 we saw a huge spike in landslides in all the valleys. In 2021 there was the Rishi Ganga disaster in which 200 workers were killed in the tunnel after the glacier fell apart. Then there was the Joshimath land sinking, the Silkayara tunnel and major rain disaster in Yamuna valley this monsoon. It is relentless. We are 100% sure that cloudburst frequency has gone up. The impact of cloudburst is also much more devastating now because of the amount of debris involved. Glaciers are melting and the debris from the glaciers are flowing with the river water. This is causing extensive damage every time,'said Mallika Bhanot, environmentalist and member of Ganga Ahvaan, a civil society collective.
But there are man made factors making things worse
'Increased development activity in vulnerable regions creates new risks to the mountain community,' said Kulkarni.
Indeed, it is important to recognize that the increase in such events in Uttarakhand is not exclusively because of the climate crisis, added Bhaot.
' You can see the anthropogenic signature in every such disaster. In the videos we can see hotels, big buildings right on the river bed. The river will take its route. It is only natural to expect that it will flow freely. Any hindrances to its flow will obviously cause disasters. The massive increase in the number of landslides is again completely linked to road construction on the Char Dham route,' added Bhanot.
The government has pushed through this project citing security concerns -- it goes right up to the India-China border -- but there is no denying that it has increased the fragility of already vulnerable hills.
NDMA scientists have not ruled out glacier breach/avalanche event:
'We have received a status report from the Ministry of Jal Shakti which says that a suspected cloudburst is likely to have triggered the disasters. IMD had also issued an orange alert for Uttarkashi. We are assessing three probable scenarios. One, there was a cloudburst in the catchment of Khir Ganga. Second, there was prolonged rainfall in the upper reaches of Western Himalayas that saturated the soil and water could not percolate any further. Third, there are 13 large glacial lakes in Uttarakhand and this may be an ice-rock avalanche from one of those lakes. This needs deeper analysis. We will also check if infrastructure played a role in the post disaster assessment depending on the need,' said Dipali Jindal, senior consultant, National Disaster Management Authority.
'These kind of rainfall events were rare and take place once in 20 or 50 years. However nowadays such events are becoming frequent due to climate change. Such mudslide normally happens when there is very heavy rain upstream. In the videos, we can see dense settlements near the river bank. These come in the right of way of the river. We should have a safe zone for buildings, hotels, habitations. Zonation is v important in such regions,' said Manish Shrestha, Hydrologist, International Centre for Integrated Mountain Development (ICIMOD).