Unusually warmer weather this winter has even impacted the extreme winter sports like ice hockey and 105-kilometre Chadar trek in the cold desert mountains of Ladakh, where minimum temperature drops up to minus 40 degree Celsius and is considered the country’s coldest place.
Amit Pandey
Ice hockey rinks in Ladakh’s Kargil town witnessed rare scenes on January 13-14 when the organisers switched on fans in the night to add to the freezing temperatures.
“The formation of the ice surface was not up to the mark this year. It could have proved dangerous for those practicing and playing ice hockey matches. Electric fans helped in the freezing process and made the rink playable and safe,” an ice hockey player from Kargil said. However, ice hockey was not majorly impacted in Ladakh’s Leh.
Officials of the Department of Youth Services and Sports said the extra measure in Kargil was put in place for “the safety of players”.
Ice hockey required around minus four Degree Celsius to provide a favourable environment. However, days have been warmer and brighter this season in Ladakh’s Kargil.
“The months of November and December have been much warmer than last year in Ladakh. Snowfall is also deficient,” Sonam Lotus, director of the Meteorological Department in Ladakh, said.
According to MeT figures, there has been a deviation of four to eight degrees in temperature from the normal weather pattern in Ladakh.
The impact of unusual weather was also visible on the 105 km Chadar trek this year, where trekkers from across the globe trek over the frozen Zanskar river connecting Kargil with Leh.
The Chadar trek was shortened this year due to late formation of ice sheaths over Zanskar river. It started six days late compared to last year, when the trek was flagged off on January 8 compared to January 14. Most trekkers have registered for four night and five days trek this year compared to eight-nine days when the lake is completely frozen and the temperature drops below minus 30 degree Celsius.
Officials said a recce team visited the Chadar trek in the first week of January and “described it risky for adventurers”. In the latest recce conducted the last week, a team of Union Territory Disaster Relief Team and Ladakh Mountain Guides Association found that up to 15 km Chadar trek was “formed very well”.
The Chadar trek is one of the extreme sports in the country and is held only when temperature drops between -30 to -35 degrees. However, the minimum temperature has been hovering around minus eight degree Celsius in Leh in January and the maximum around four degree Celsius.
According to MeT figures, Leh has recorded a scant 1.2 centimetres of snowfall in November-December compared to 2.6 cm last year for the same period. The snowfall in 2013 was the highest when 13.6 cm of snowfall was recorded. Ladakh is home to the second coldest place in the world, Drass, where temperature could even dip below minus 50 degree Celsius.
The engines driving the growth of the world’s highest mountains into the sky run deep beneath the planet’s skin. Geologists have some idea of the mechanisms at work, but evidence has so far left plenty of room for debate over the details.
Combined with a fresh look at previous research, a recent analysis of new seismic data collected from across southern Tibet has delivered a surprising depiction of the titanic forces operating below the Himalayas.
Presenting at the American Geophysical Union conference in San Francisco last December, researchers from institutions in the US and China described a disintegration of the Indian continental plate as it grinds along the basement of the Eurasian tectonic plate that sits atop it.
It’s a surprising compromise on two models currently favored as explanations for the lifting of the Tibetan plateau and the colossal Himalayan mountain range.
In both cases, a collision between the chunks of crust belonging to India and Eurasia is responsible. Starting around 60 million years ago, the Indian plate was driven beneath its northern neighbor as it was carried along by currents of molten rock within the mantle.
Bit by bit, the Eurasian land mass has been lifted skyward on the shoulders of a drowned giant, giving us Earth’s highest elevations.
Studies of the density of the mantle and the crust suggest the rather buoyant Indian continental plate shouldn’t sink so easily, however, meaning it’s likely the submerged sections of the crust should still be grinding along under the belly of the Eurasian plate rather than being plunged into the mantle’s depths.
Another possibility is the Indian plate is distorting in a way that causes some parts to wrinkle and fold, and others to dip and dive.
Different perspectives emerge depending on which kinds of evidence are favored and how data is processed.
In an investigation led by Ocean University of China geophysicist Lin Liu, researchers amassed ‘up-and-down’ S-wave and shear-wave splitting data from 94 broadband seismic stations arranged west-to-east across southern Tibet, and combined it with previously collected ‘back-and-forth’ P-wave data to come up with a more nuanced view of the dynamics below.
They determined the Indian slab wasn’t merely bobbing along smoothly below the Eurasian plate, nor was it bunching up like a rug on a slippery floor.
Instead it is delaminating, with its dense base peeling free and sinking into the mantle as its lighter top-half continues its journey just beneath the surface.
While computer models had suggested thicker sections of some plates could come apart like this, the study provides the first empirical evidence of it occurring.
The team’s description is consistent with geological models based on limits of helium-3 enriched spring water and patterns of fractures and earthquakes near the surface, which taken together support a map of carnage below, where sections of the old Indian plate seem more or less intact, and others are stripping apart around 100 kilometers below, allowing the base to warp into the planet’s molten heart.
Having a clear 3D description of the boundaries and borders of plates as they grind together not only makes it easier to understand how our surface came to look as it does, but could inform future methods of earthquake prediction.
The study was presented at the 2023 American Geophysical Union conference.
