Why the Autumn Climbing Season Became Fatal in the Himalayan Mountains
Clear heavens, calm winds and a panoramic vista of Himalayan peaks draped in snow - this describes the fall setting that trekkers on the world's highest peak have come to love.
However this seems to be shifting.
Shifting Weather Patterns
Meteorologists report the rainy season now stretches into fall, which is traditionally the high-altitude tourism period.
During this prolonged tail end of monsoon, they have observed at least one occurrence of heavy precipitation almost every year for the previous decade, with mountain conditions becoming more dangerous.
Latest Emergency on Everest
Recently, a shock snowstorm stranded hundreds of travelers near the east-facing face of Everest for multiple days in bitterly cold conditions at an altitude of more than 16,000ft.
Approximately 600 hikers were guided to safety by the conclusion of that week, according to reports.
A single person had died from hypothermia and altitude sickness, but the remaining individuals were reportedly in good condition.
Comparable Events Across the Region
This was on the northern side but a comparable situation had occurred on the southern side, where a South Korean mountaineer lost his life on another Himalayan summit.
The world found out after some delay because communication lines were affected by heavy downpours and heavy snowfall.
Authorities estimate that landslides and flash floods in the country have killed around 60 people over the previous week.
"It is very atypical for October during which we expect the skies to stay clear," commented an experienced mountain guide.
Economic Impact
Considering this is the preferred period, regular storms like these have "disrupted our trekking and climbing business," he added.
The monsoon season in the Indian subcontinent and the Himalayan nation typically continues from early summer to early autumn, but not anymore.
"Research demonstrates that most of the years in the previous decade have had rainy seasons continuing until the second week of October, which is definitely a shift," explained a high-ranking weather official.
Increasing Weather Severity
Even more concerning is the intense rain and snowfall the tail end of the period produces, like it occurred this time on 4 and 5 October.
High in the Himalayas, such severe weather means blizzards and winter storms, which constitutes a huge risk for hiking, mountaineering and the travel industry.
Personal Accounts
That's what occurred last weekend when the weather shifted quite suddenly - the air currents began roaring, temperatures plummeted and visibility dropped drastically.
The road that had easily led the hikers to what should have been a breathtaking pitstop was now buried in snow and extremely difficult to traverse.
Still, one hiker, who had climbed the Himalayas more than a dozen times, reported he had "never encountered weather like these" before.
Scientific Explanations
A primary major driver is the increased quantity of moisture in the atmosphere because of how the world has been heating up, scientists say.
This has led to heavy precipitation over a short span of duration, often after a extended dry spell – in contrast to in the previous era when monsoon showers were spread uniformly over four months.
A Turbocharged Monsoon
Climate specialists report the monsoons in South Asia at times seem to have become more intense because they are increasingly interacting with an additional atmospheric phenomenon, the westerly disturbance.
This is a low pressure system that originates in the Mediterranean area and moves eastward - it transports cold air that brings precipitation and occasionally snow to northern India, Pakistan and Nepal.
Global Warming Effects
Scientists have also discovered that in a warming planet, the increasing relationship between westerly disturbances and seasonal rains is producing another atypical outcome.
The hotter air is forcing the weather systems to greater altitudes, which means these atmospheric conditions are now able to pass over the mountain barrier and affect the Tibetan plateau and other areas that previously experienced less so much precipitation in the past.
"What's changed is the reliability of patterns; we can't assume that conditions will occur the identical from year to year," said an seasoned expedition leader.
"That means flexible planning, real-time decision-making, and knowledgeable leadership [in the Himalayas] have become even more crucial."
