New Record Early July Low For Arctic Sea Ice; Siberian Heat Flowing Out Over Laptev Sea
Sea ice cover in the Arctic Ocean hit a record low on Monday for this time of year, surpassing even the year 2012 which went on to see the lowest annual minimum extent since satellite records began in 1979. Extent fell to 8.867 million square kilometers (3.4 million square miles) of ice cover on July 5, 2021.
This year’s early July drop was unexpected by some observers due to a cool stormy spring in the Arctic which in the past might have put a brake on the melt season, though a Russian heatwave is now stoking Laptev Sea melt, while warmth over Hudson Bay has caused ice there to disappear earlier than typical. Ice extent in 2020 (the second lowest extent record holder) tracked fairly closely to 2021, though above what we’re seeing right now. However, spring and early summer 2020 were hotter and sunnier than this year, meaning that the thinner first year ice seems to be melting at record rates despite cooler, stormier weather conditions.
EDIT
In 2020, the Laptev Sea was at its lowest ice extent on record from late June until early November, corresponding with a huge heatwave which pummeled Siberia. On June 17, air temperatures of around 38 degrees Celsius (100.4 degrees Fahrenheit) were recorded in Verkhoyansk, a city south of the Laptev Sea. Moreover, the record-breaking heatwave coincided with the summer solstice, the longest day of the year, when solar radiation is at its highest. All of this solar heat absorbed by the dark ocean water likely stalled the ice’s regrowth come autumn, contributing to this year’s record low.
The heat over Siberia hasn’t abated much — scientists say that western North America and northeast Asia are now the world’s two fastest-warming spots in summer. This year, the town of Oymyakon, Russia, considered the coldest inhabited place on Earth, reached 31.6 degrees Celsius (88.8 degrees Fahrenheit) on June 29, the hottest it’s ever been at this time of year. That heat is now flowing out over the Laptev Sea.
EDIT
https://news.mongabay.com/2021/07/as-arctic-melt-sets-early-july-record-hard-times-lie-ahead-for-ice-studies/
