Record polar vortex last November

The southern polar vortex
The southern polar vortex. NASA image

We had powerful gales in southern Tasmania in December, after a fairly wet early November.

Gales are hardly abnormal here, but these seemed special, anecdotally speaking, based on my 10 years on the farm.

In Judbury, the grass up the hill was pressed hard against the ground for three days in footage from my trailcam video.

A tree fell locally and killed two cows.

Even when it wasn’t a gale front, it blew hard.

There was plenty of drizzle in December, but it evaporated off the soil. Very little soaked in.

Interestingly, the southern hemisphere had a record strong polar vortex event in November 2020 before the gales.

The polar vortex is the wind that spins around the earth’s poles at high altitude.

When the vortex is strong and cold over the South Pole it brings rain to Australia’s East Coast, and low temperatures.

When the vortex is weak, it brings drought, heat and fires.

I am unsure if the vortex brought the gales, as the vortex is 30km high, separate from land and ocean winds.

But it does affect the weather in complex ways.

Here’s the kicker, 2019 was an unusually weak vortex year, with sudden stratospheric warming.

The 2019 Australian fires were a true disaster.

Right now the North Pole is having a vortex breakdown, something that happens more often with global warming.

This brings unusual blizzards to some northern hemisphere countries, and when that happens climate change deniers say: “Look, it’s getting colder!”

What they don’t see, unless they look for it online, is the huge lump of heat over Greenland that forms during vortex breakdowns.

If you have been paying attention, you’d know Greenland ice melt has been off the scale in recent years, and being a massive ice sheet sitting on land, it’s melt will raise global sea levels.

We live in interesting times.

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Tasmanian Life