The climate system is unraveling rapidly.
The National Weather Service Fairbanks detected a strange lightning storm over the sea ice in the Arctic ocean that numbered between 100 and 200 strikes and brought torrential rain to the sea- ice exacerbating sea ice decline. The storm is strange because lightning is a warm-weather phenomenon that requires the sun's heat to warm the air, rising and producing water droplets.
The Cloud Appreciation Society notes the entire process (in a nutshell).+
Out in the atmosphere, patches of sun-warmed ground can act as enormous radiators that set the air rising. These convection currents are known as thermals, and produce fair-weather Cumulus clouds. But convection can also produce clouds when the Sun is not shining. This happens when a huge region of colder air from the poles collides with a region of warmer air from the tropics. When this happens, some of the colder air can ride up over the warmer. The result is in an unstable region of the atmosphere that produces large convection clouds. The less dense, warmer air below rises rapidly through the denser, cooler air above. And whenever air rises like this it cools. This means that some of the invisible water vapour it contains can condense into droplets that appear as cloud.
Historically these types of moisture-laden storms in the Arctic are rare. Not so anymore as warmth has penetrated the region three times faster than the rest of the planet and amplifying dangerous feedbacks; the relentless warming has ushered in the tipping of the Arctic.
Matthew Capucci writes in Washington Post:
What made Monday’s storms so unusual, however, is just how far north the storms ventured — well north of Prudhoe Bay, directly over sea ice. The Weather Service in Fairbanks estimates that thunderstorms like that may develop so far north only once or twice every decade.
Additional storms were erupting in the Chukchi Sea east of Russia and Siberia on Tuesday evening, drifting toward northern Alaska and Point Barrow once again.
Unusually warm air has helped fuel the storms. On Monday, Prudhoe Bay rose to a toasty 73 degrees.
“The setup associated with the record temps originated from a thermal low over Eastern Siberia,” Jason Ahsenmacher, lead meteorologist at the Weather Service in Fairbanks, wrote in an email. A thermal low is a weak low-pressure system induced by exceptional heating, the warmth forcing air to rise and expand, creating a relative pressure deficit near the ground that draws in air from all directions.
Meanwhile, several disturbances were transiting the Arctic, including one with divergent flow at high altitudes. That spreading of the wind at the mid- to upper levels of the atmosphere created an almost vacuum-like effect, making it easier for surface pockets of air to rise. That effect also amplified a river of warm, moist air being tugged northward, providing copious fuel for fledgling downpours and thunderstorms to feed on.
“Moreover, southwest winds will also have a downslope warming/adiabatic compression component which aided in pushing temps to record levels,” Ahsenmacher wrote. In other words, the air cresting over Alaska’s North Slope blowing in from the south sunk as it reached lower elevations, causing it to warm.
The article notes that ‘high latitude lightning’ is not rare, but the unstable air mass over the arctic generated its own lightning that has raised alarms.