At solar minimum, the largest ozone hole over Antarctica in years

Posted: October 7, 2020 by oldbrew in atmosphere, Clouds, Natural Variation, ozone


As Accuweather explains here, research has shown that a combination of conditions at solar minimum can create this effect.
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The European Union’s Earth observation program said Tuesday that the ozone hole over Antarctica has swelled to its largest size and deepest level in years, reports

Experts at the Copernicus Atmospheric Monitoring Service said a strong, stable and cold polar vortex has driven the expansion, and called for greater international efforts to ensure countries abide by an international accord to phase out use of ozone-depleting chemicals.

Vincent-Henri Peuch, who heads the service, said in a statement that the ozone hole was “definitely” among the largest in the last 15 years.

Ozone depletion over the Antarctic continent was first noticed in 1985.

In Geneva, spokeswoman Clare Nullis of the World Meteorological Organization said the ozone hole begins to expand every August—at the start of the Antarctic spring—and reaches a peak around October.

“The air has been below minus 78 degrees Celsius, and this is the temperature which you need to form stratospheric clouds—and this quite (a) complex process,” Nullis said at a U.N. briefing.

“The ice in these clouds triggers a reaction which then can destroy the ozone zone. So, it’s because of that that we are seeing the big ozone hole this year.”

Full report here.

  1. JB says:

    So which is it, ice crystals coupled with seasonal changes, or hydrofluorcarbons?

    They keep looking at effects, not causes.

  2. pochas94 says:

    Ozone – good or bad? Does the large ozone hole mean we’re all gonna die from too much ultraviolet so we must keep from emitting nasty ozone depleting chemicals. or does ozone cause terrible health issues like lung diseases such as asthma, emphysema, and chronic bronchitis? The people need to know.

  3. pochas94 says:

    “So which is it”
    It’s a complex mishmash of physics completely impenetrable to “scientists” who make a handsome living by selective ignorance.

  4. oldbrew says:

    Polar stratospheric clouds (PSCs) are clouds in the winter polar stratosphere at altitudes of 15,000–25,000 m (49,000–82,000 ft). They are best observed during civil twilight, when the Sun is between 1 and 6 degrees below the horizon, as well as in winter and in more northerly latitudes.[1] One main type of PSC is made up mostly of supercooled droplets of water and nitric acid and is implicated in the formation of ozone holes.[2] The other main type consists only of ice crystals which are not harmful.
    . . .
    PSCs form at very low temperatures, below −78 °C (−108 °F). These temperatures can occur in the lower stratosphere in polar winter.

    [bold added]
    – – –
    So the stratosphere hasn’t been cold enough, so far this season, but that seems to be normal anyway. This NASA animation of PSCs doesn’t even start until November…

    Quote: ‘Note how the area covered by the clouds increases as winter progresses.’

  5. oldbrew says:

    Do cosmic rays destroy the ozone layer?
    26 Mar 2009

    New data gathered from satellites and ground-based stations support the idea that much of the destruction of Antarctic ozone involves the action of cosmic rays, says a physicist in Canada. This goes against the widely-accepted notion that the ozone layer — which shields Earth from harmful ultraviolet radiation — is depleted via the action of direct sunlight.

    Qing-Bin Lu of the University of Waterloo also predicts, given the timing of the 11–year cosmic-ray cycle, that the ozone hole will be particularly large in 2008–09 and 2019–2020 (Phys Rev Lett 102 118501 ).

    Lu goes further:
    He also found a correlation between cosmic ray intensity and the fluctuation in ozone in the Antarctic (between latitudes of 60 and 90 degrees S) from one October to the next between 1990 and 2007.

    Any non-cosmic-ray related mechanism, if it exists, must be a very minor or negligible effect

    Qing-Bin Lu, University of Waterloo

    “These correlations mean that nearly 100% of the ozone loss over Antarctica must be driven by cosmic rays,” he says, pointing out that the degree of variation of cosmic ray intensity and Antarctic ozone are very similar (both about 10%). “In other words, any non-cosmic-ray related mechanism, if it exists, must be a very minor or negligible effect.”
    [bold added]
    – – –
    Lu is not impressed by the alarmist CFC argument.

    NB his 2019-2020 forecast is one year too early because the solar cycle just ending was over 12 years long instead of his 11 years estimate.