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British
Antarctic Survey
Ozone Bulletins
Situation at 2009 December 30
The 2009 ozone hole is over, with
the continent having experiencing the final stratospheric spring warming.
Ozone values across the continent are around 300 DU, and the summer circulation
is established. Ozone values in surrounding areas are generally lower than
over the continent The temperature of the ozone layer over Antarctica is
at its summer maximum and is now far too warm for polar stratospheric clouds (PSCs)
to exist. During the early winter, the polar vortex was often rather more
elliptical than it was in 2008, and this lead to some early depletion in
circumpolar regions as stratospheric clouds became exposed to sunlight.
It reverted to a more circular circulation as winter progressed and this led to
another relatively slow start to the growth of the ozone hole (as measured by
NASA/SBUV2), with the "hole" not beginning until mid August. The
vortex became more elliptical again in late August, with South Georgia being
affected by the fringes of the ozone hole between September 2 and 6. The
hole grew to reach an area of around 24 million square kilometres by mid
September, and then lasted until the end of November, although the final
remnants of the polar vertex lingered until towards the end of the month.
From mid August to mid November it remained around the average area seen over
the past decade. The tip of South America and South Georgia were affected
by the fringes of the ozone hole from September 24 to September 30, from October
3 to October 7 and from November 8 to 25. South Georgia was affected on
November 6.
See the final
situation report for last year for information on the 2008 - 2009 season.
Notes: The Antarctic
ozone hole is usually largest in early September and deepest in late September
to early October. September 16 is world ozone day, and in 2009 the final
UN Member State to ratify the Montreal Protocol signed up. 2007 was the
International Year of the Ozone Layer. Prior to the formation of ozone
holes, Antarctic ozone values were normally at their lowest in the autumn (ie
March).
Final ozone layer situation reports
The BAS ozone web page is updated regularly, with the situation report from
the final update of the season being archived.
BAS issues regular ozone bulletins. Issues available are:
- 1
(02/11/01), 2
(2001/02 summary) (28/05/02).
- 1
(02/10/00), 2
(07/11/00), 3
(30/01/01). 4
(2000/01 summary) (11/05/01).
- 1
(06/09/99), 2
(20/09/99), 3
(04/10/99), 4
(20/10/99), 5
(1/11/99), 6
(11/11/99), 7
(30/11/99), 8
(17/12/99), 9
(10/01/00), 10
(14/02/00), 11
(12/04/00), 12
(1999/2000 summary) (02/06/00).
- 1
(24/08/98), 2
(22/09/98), 3
(02/10/98), 4
(15/10/98). 5
(30/10/98), 6
(13/11/98), 7
(1998/99 summary) (13/05/99).
- 1
(15/08/97), 2
(29/08/97), 3
(05/09/97), 4
(12/09/97), 5
(19/09/97), 6
(26/09/97), 7
(03/10/97), 8
(10/10/97), 9
(17/10/97), 10
(24/10/97), 11
(31/10/97), 12
(07/11/97), 13
(14/11/97), 14
(21/11/97), 15
(08/12/97), 16
(09/01/98), 17
(06/02/98), 18
(1997/98 summary) (25/05/98).
- Summary
(15/08/97), 1
(30/08/96), 2
(10/09/96), 3
(15/09/96), 4
(20/09/96), 5
(27/09/96), 6
(7/10/96), 7
(14/10/96), 8
(18/10/96), 9
(28/10/96), 10
(1/11/96), 11
(10/1/97), 12
(20/1/97)
- Summary
- 5
(22/09/95), 6
(02/10/95), 7
(06/10/95), 8
(13/10/95), 9
(23/10/95), 10
(30/10/95), 11
(03/11/95), 12
(10/11/95), 13
(17/11/95), 14
(03/12/95), 15
(10/12/95), 16
(19/12/95), 17
(11/06/96).
- Summary
- Summary
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