How the Fall Trekking Season Became Lethal in the Himalayan Mountains
Bright heavens, calm winds and a breathtaking view of majestic peaks draped in white powder - that is the fall experience that hikers on the world's highest peak have grown to adore.
But that appears to be shifting.
Changing Climate Conditions
Weather experts say the rainy season now stretches into fall, which is traditionally the high-altitude travel period.
Throughout this delayed tail end of the rainy season, they have recorded at least one occurrence of extreme rainfall almost every year for the past decade, with high-altitude conditions becoming increasingly risky.
Recent Crisis on Everest
Last weekend, a unexpected blizzard trapped several hundred of visitors near the eastern side of Everest for multiple days in bitterly cold temperatures at an altitude of more than 4,900m.
Almost six hundred hikers were guided to security by the conclusion of Tuesday, according to reports.
One individual had succumbed from hypothermia and altitude sickness, but the remaining individuals were said to be in good health.
Comparable Incidents Across the Region
This was on the Tibetan slope but something similar had developed on the southern side, where a Korean climber lost his life on another Himalayan summit.
The international community learned after some delay because communications were hit by torrential rains and heavy snowfall.
Authorities estimate that landslides and sudden floods in the country have claimed the lives of approximately 60 people over the past seven days.
"It is very atypical for October during which we expect the weather to stay calm," commented an experienced mountain guide.
Business Consequences
Given this is the preferred season, regular extreme weather events like these have "disrupted our trekking and mountaineering industry," he continued.
The monsoon season in the Indian subcontinent and Nepal typically lasts from early summer to early autumn, but not anymore.
"Research shows that most of the years in the previous decade have had rainy seasons lasting until the second week of October, which is definitely a shift," said a senior meteorology expert.
Increasing Weather Severity
Even more concerning is the intense precipitation and snow the tail end of the period brings, like it occurred this time on 4 and 5 October.
High in the mountain range, such severe conditions means blizzards and snowstorms, which constitutes a significant danger for hiking, mountaineering and tourism.
Personal Experiences
Exactly what happened last weekend when the conditions shifted quite abruptly - the air currents began roaring, temperatures plummeted and sightlines decreased drastically.
The road that had comfortably brought the hikers to what should have been a breathtaking resting point was now buried in snow and extremely difficult to navigate.
Still, one hiker, who had climbed these mountains more than a twelve times, reported he had "not once experienced conditions like these" before.
Expert Explanations
A primary big factor is the increased amount of humidity in the air because of how the planet has been warming, scientists explain.
That has led to torrential rains over a short span of time, often after a extended dry spell – in contrast to in the past when seasonal rains were spread uniformly over four months.
A Turbocharged Monsoon
Climate experts say the rainy seasons in the region at times seem to have become more intense because they are increasingly coming into contact with an additional atmospheric phenomenon, the western weather pattern.
The phenomenon is a atmospheric depression that forms in the Mediterranean area and moves eastward - it carries cold air that causes rains and sometimes snowfall to northern India, Pakistan and the Himalayan region.
Global Warming Effects
Researchers have additionally discovered that in a warming planet, the growing relationship between westerly disturbances and monsoons is causing an additional unusual outcome.
The hotter atmosphere is pushing the weather systems to greater altitudes, which means these weather systems are now able to cross the Himalayas and affect the Tibetan plateau and other areas that previously experienced less as much precipitation in the past.
"What's changed is the reliability of weather patterns; we can't assume that conditions will behave the same from season to season," commented an seasoned mountain guide.
"That means flexible planning, immediate choices, and knowledgeable leadership [in the Himalayas] have become increasingly essential."
