Sudden Stratospheric Warming (SSW) event above South Pole to go down as the strongest on record

Sudden Stratospheric Warming (SSW) event above South Pole to go down as the strongest on record

Very rare Sudden Stratospheric Warming (SSW) event continues unfolding above the South Pole.

This SSW could go down in history as the strongest warming event on record, NIWA said, adding there is increased risk for southerlies in New Zealand into October. 

SSW events are rare in the southern hemisphere, with only two in New Zealand in recorded times - one in September 2002 and the other in September 2010

The Australian Bureau of Meteorology is also predicting it as the strongest Antarctic warming on record, likely to exceed the previous record of September 2002 when New Zealand experienced its coldest October in 20 years.

Below-average temperatures covered much of the country in 2002, resulting in frequent ground frosts.

In 2010 SSW event – which is classed as a minor event – a number of rainfall records were broken with well below normal sunshine and very cold temperatures in parts of the South Island.

"Although we have seen plenty of weak or moderate variations in the polar vortex over the past 60 years, the only other true sudden stratospheric warming event in the Southern Hemisphere was in September 2002," BOM meteorologists said.

"Impacts from this stratospheric warming are likely to reach Earth’s surface in the next month and possibly extend through to January. Apart from warming the Antarctic region, the most notable effect will be a shift of the Southern Ocean westerly winds towards the Equator.

"For regions directly in the path of the strongest westerlies, which includes western Tasmania, New Zealand’s South Island, and Patagonia in South America, this generally results in more storminess and rainfall, and colder temperatures. But for subtropical Australia, which largely sits north of the main belt of westerlies, the shift results in reduced rainfall, clearer skies, and warmer temperatures.

"Past stratospheric warming events and associated wind changes have had their strongest effects in NSW and southern Queensland, where springtime temperatures increased, rainfall decreased and heatwaves and fire risk rose."

Temperatures have been below average month-to-date in New Zealand's South Island, NIWA said September 10. 

Temperatures in central Otago plummeted to -5 °C (23 °F) today, forcing farmers to crank up frost fighting efforts with machines and helicopters, Newshub reports

Tim Jones, chief executive of 45 South Orchard and Packhouse in Cromwell, says the cold is expected to stick around for another month. 

"The last one in 2002 I do recall had an awful lot of frosts right throughout the spring," he said. "Particularly leading on into October and November. Who knows whether we're up for that again this year, but the key thing is that we're prepared for it."

Featured image credit: Dave See

Comments

goldminor 2 days ago

After a cool summer here in Northern California area temps are set to drop below 60 day/40 night F in 7 days. That is an early onset of cool for this area. A storm passed through over the last 4 days bringing intermittent early rains to this mountain area. There is more on the way in 3 days. This reminds me of when I was young back in the 1950s/60s in SF. On occasion the rains would start in September. That would typically lead to an overall wetter than average winter for the West Coast. The central and eastern parts of the US are headed for a cold winter though. Russia and Europe will also face below average temps during this winter. There will be some crop losses from all of this as fall arrives early. Especially after the miserable spring conditions of 2019. The spring of 2020 should be as bad or potentially worse as this is the heart of the ongoing solar minimum. The minimum will likely break after July 2020. Then we wait and see what happens next. Many think that SC 25 will be similar to the outgoing SC 24. Some say even lower, but no one knows for certain.

André 8 days ago

Since 1859, the IPCC reports have ignored the shifting and changing geomagnetic field. Together with the solar cycle and cosmic rays, this gives a totally different magnetic field distribution in the stratosphere, resulting in altered weather images

André Hermans 11 days ago

The temperature curves at 10hPa from the South Pole are incorrect. I noticed with app from (EARTH nullschool net) that on 2019/07/26 03:24 (CEST) -27.8 ° C at 57.08° S, 15.44° E on 2019/08/14 15:40 (CEST) -31.5 ° C at 65.25° S, 75.42° E on 2019/09/6 02:53 (CEST) -3.5 ° C at 74.04° S, 29.95° E on 2019/09/8 11:12 (CEST) +1.8 ° C at 82.35° S, 39.73° E on 2019/09/10 11:35 (CEST) +3.2 ° C at 78.83° S, 57.60° E on 2019/09/11 08:39 (CEST) +17.0 ° C at 79.04° S, 69.93° E the magnetic south pole is fixed at 64.10 S, 135.8° E

moriyah 12 days ago

Here in Canada we are watching to see if the sudden warming over Antarctica will produce a compensatory sudden cooling over Greenland in particular but also Scandinavia and Nunavut along with eastern North America. Already we are expecting a very cold winter but if Fall starts early then Winter may as well. Will it last longer also? Will it flood our Capital city Ottawa like never before? Even more than 2 out of the last 3 spring freshets? I'm betting yes. The weather in the southern hemisphere DOES impact the northern hemisphere and vice versa. Why would it not?

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