Context: Recently, the Arctic Circle has recorded temperatures reaching over 38 degrees Celsius in the Siberian town of Verkhoyansk, likely an all-time high. The temperatures seem to have been 18 degree Celsius higher than normal in June a/c to the BBC.
Issue

• The recorded temperature at 38 degrees is around 18°C higher than the normal temperature for this time of the year for the place.
• The town is in the Guinness book of world records for the largest temperature range it experiences — from some -67 °C to some 37°C.
• This new record has an imprint of global warming and the impact of such warming can be witnessed even here in India.
• The new high shows temperature swings may be increasing.

Are Arctic heatwaves common?

• This is not the first time that rising temperatures in the Arctic have created alarm.
• The rising temperatures are attributed to large-scale wind patterns that blasted the Arctic with heat, the absence of sea ice, and human-induced climate change, among other reasons.
• There has been an increase of heatwave occurrences over the terrestrial Arctic. These frequent occurrences have already started to threaten local vegetation, ecology, human health and economy.

A cause of worry for all

• Warming in the Arctic is leading to the thawing of once permanently frozen permafrost below ground.
• This is alarming scientists because as permafrost thaws, carbon dioxide and methane previously locked up below ground is released.
• These greenhouse gases can cause further warming, and further thawing of the permafrost, in a vicious cycle known as positive feedback.
• The higher temperatures also cause land ice in the Arctic to melt at a faster rate, leading to greater run-off into the ocean where it contributes to sea-level rise.

Western disturbances

• The impacts of a warming Arctic are not limited to the region but can be felt even in India.
• Ex: western disturbances respond to the pressure variations associated with the jet stream swings.
• The western disturbances are extra-tropical storms that originate in the Mediterranean and travel to India on the sub-tropical jet stream.
• They cause rainfall in north west, northern and north eastern India during the winter and spring months and snowfall in the high altitude regions.
• This year, they were particularly active and caused heavy rainfall in March, April and May over northern and north western India.
• These rains, moisture and the vegetation they produced was partly responsible for the early locust attacks in Rajasthan this year which spread as far east as Chhattisgarh for the first time in decades.