As per news reports, the death toll in Uttarakhand was 52 while 5 people were missing. Nainital was the worst affected district which saw the highest death toll of 28 deaths.
According to a briefing by Climate Trends, India, untimely rains which led to overflowing rivers and lakes or flowing close to the danger marks is an effect of the extended stay of monsoon. Meteorologists believe that the state wouldn’t have witnessed such torrential rains had the monsoon retreated on time. The presence of monsoon current continued to drive moist winds and weather systems over the plains.
“It’s very evident that had the monsoon departed timely, we wouldn’t have seen such torrential rains. Weather conditions were very favourable for such heavy precipitation on account of multiple weather systems coming together,” GP Sharma, President of Meteorology and Climate Change, Skymet Weather was quoted as saying.
Also Read: Death toll due to heavy rainfall, flash floods and landslides in Uttarakhand rises to 52; 5 missing
From October 1 and October 20, Uttarakhand recorded a whopping 192.6 millimetre (mm) of rainfall, out of which 122.4 mm of rainfall was recorded in just 24 hours.
What caused heavy rainfall in Uttarakhand and Uttar Pradesh?
The briefing paper pointed out that a low-pressure area traveled along with the Northern Limit of Monsoon (NLM) that was then passing through parts of Central India. It later moved north towards Uttarakhand and then recurved towards Uttar Pradesh.
Once the monsoon retreated, dry northwesterly winds started blowing over North India. However, the presence of multiple weather systems led to a change in wind patterns. This led to strong humid easterly winds (winds coming from the east) all along the Indo-Gangetic plains with a depth of more than 8,000 feet (ft).
Also Read: Explained: How air pollution affects monsoon rains in India
Both the low-pressure areas travelling in the Bay of Bengal were the remains of tropical storms Lionrock and Kompasu in the Pacific ocean that re-emerged in Indian seas and gathered strength. While Lionroch affected Madhya Pradesh, Kompasu travelled to West Bengal, Bihar and the entire Northeast India region.
Talking about the rare development of weather systems over the plains during this time of the year, Sharma added, “There was a western disturbance up in the hills, two low-pressure areas were seen over Madhya Pradesh and Bay of Bengal, respectively. We do not see much impact of any western disturbances over the northern states other than some light showers. Usually, we start witnessing changes in the track of western disturbances by the end of October but both the intensity and frequency of Western Disturbances increase by November only.”
Late withdrawal of Southwest Monsoon
Increasing global temperatures are changing monsoon patterns across Southeast Asia as per the latest report by the United Nations led Intergovernmental Panel on Climate Change (IPCC) Working Group, titled “Sixth Assessment Report Climate Change 2021: The Physical Sciences Basis”.
Very dry weather and climate events and seasons are intensified by a warmer climate, which leads to floods and droughts. The location and the frequency of these events also depend on projected changes in regional atmospheric circulation, including monsoons and mid-latitude storm tracks.
Since monsoon has been breaching its normal withdrawal date for many years now, the state-run India Meteorological Department (IMD) has also revised the commencement date of monsoon withdrawal from September 1 to September 17. The withdrawal process would be completed by October 15, however, this has not been the case for the last decade.
Displaced development
It’s pertinent to note that destruction due to inclement weather conditions is not only due to the climate crisis but other factors play a vital role too. Development plans and human interference are two key reasons behind the ecological imbalance in Uttarakhand.
Talking about the sensitivity of Higher Himalayas, both climatically and tectonically, Professor Y.P. Sundriyal of HNB Garhwal University said, “Mega hydro-projects should be avoided or should be carried out on a small scale. Additionally, road construction should be done with scientific techniques.” He also added that if roads are built with slope stability, good quality retaining wall, and rock-bolting then the damage done by landslides would be restricted to some extent.
The influx of tourists over the year has led to an increase in vehicular, river pollution and also led to construction activities, and commercialization, noted Atul Satti, a local environmental activist. “Construction of hydropower projects along with road widening activities have contributed to the increase in temperatures along with a change in rainfall pattern. We now see incessant rains that go on for two to three days at a stretch while several days are left high and dry,” Satti said.
Rising climate risk in Uttarakhand
This isn’t the first time the Himalayan state has been hit by heavy rainfall-induced disaster leading to loss of lives and property. Earlier this year in February, an avalanche in Chamoli district led to flash floods that killed over 200 people and washed away two hydropower projects.
An analysis by Council on Energy, Environment and Water (CEEW India), a New Delhi-based think tank, shows how vulnerable Uttarakhand is to climatic changes. The state has recorded an increase in both extreme floods and droughts in the last five decades.
Since 1970, there has been a four-fold increase in extreme flood events in Uttarakhand. A similar increase in associated events such as landslides, cloud bursts, and glacial lake outbursts has been recorded. Chamoli, Haridwar, Nainital, Pithoragarh, and Uttarkashi districts are most vulnerable to extreme floods.
The analysis by CEEW India found a two-fold increase in droughts in the state during the same period. Over 69 per cent of districts in the state are now drought-prone. In the last decade, floods and droughts occurred simultaneously in Almora, Nainital, and Pithoragarh districts. This further complicates risk-informed decision-making for policymakers and response teams, said the think tank.
Also Read: Uttarakhand: The Himalayan state is besieged by extreme floods and increased droughts
“The recent devastating flash flood in Uttarakhand is further proof that the climate crisis can no longer be ignored,” said Abinash Mohanty, programme lead at CEEW. “In the last twenty years, Uttarakhand has lost more than fifty thousand hectares of forest cover, leading to microclimatic changes in the region. This, in turn, has triggered a rise in extreme climate events in the state,” he added.
