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2003 ANTARCTIC
OZONE ‘HOLE’ NEAR RECORD SIZE;COLD TEMPERATURES PLAY MAJOR ROLE
Oct. 7, 2003 — This
year’s Antarctic ozone “hole” is the second largest ever observed, according to
NOAA scientists. The size of the ozone depletion region shows an increase in its
total size from last year, further indicating that the relatively smaller hole
of 2002 was mostly a quirk of meteorological conditions over Antarctica. The
difference is directly attributed to year-to-year temperature variations across
the Antarctic continent, not an increase in the amount of ozone-depleting
compounds in the atmosphere.
“We expect to see year-to-year
variations in the size of the ozone hole because stratospheric temperatures can
vary from year to year. In colder years, the same amount of ozone-depleting
compounds can destroy more ozone, in comparison to warmer years,” said Daniel L.
Albritton, director of the NOAA Aeronomy Laboratory in Boulder, Colo.
The Antarctic ozone “hole” is
defined as thinning of the springtime ozone layer to levels significantly below
those seen prior to 1979. Extreme cold in the upper atmosphere is one key factor
that affects the amount of ozone loss caused by ozone-depleting compounds.
Year-to-year changes in the size and amount of depletion in the vertical column
of the ozone hole are dominated by the year-to-year variations in temperature in
this part of the atmosphere.
Chlorine- and bromine-containing
compounds from human activity are the primary cause of ozone depletion. The 1987
United Nations Montreal Protocol and its subsequent amendments sharply curtailed
the use of chlorine-containing chlorofluorcarbons (CFCs) and bromine-containing
halons. Because of the protocol, the amounts of these ozone-depleting substances
have begun to decline in the lower atmosphere and to level off in the
stratosphere, where the ozone layer resides.
“Although international protocols
have greatly reduced the production and release of ozone depleting chemicals,
they will remain active in the stratosphere for several decades,” said James
Laver, director of the NOAA Climate Prediction Center. “With the protective
atmospheric layer so compromised, greater amounts of ultraviolet radiation may
be allowed to reach the surface and potentially increase certain health risks.”
NOAA provides predictions of expected levels of ultraviolet radiation in support
of the Environmental Protection Agency’s Sunwise program.
At South Pole Station,
balloon-borne ozone-measuring instruments launched by the NOAA Climate
Monitoring and Diagnostics Laboratory reveal the vertical structure of the
developing ozone hole. An important gauge for identifying when future recovery
of the Antarctic ozone hole begins is the severity of depletion observed in the
upper atmosphere near the main ozone layer.
Ozone measured by a balloon
instrument on Sept. 26 showed nearly complete ozone destruction in the 9-13 mile
altitude layer. Total column ozone indicated a 60 per cent drop from early
August measurements.
“This year, ozone depletion over
the South Pole, from 7-to-14 miles above Antarctica, has shown large losses,
similar to losses seen in the 1990s,” said Bryan Johnson of the NOAA Climate
Monitoring and Diagnostics Laboratory.
Ozone blocks harmful ultraviolet
“B” rays. Prolonged over-exposure to ultraviolet radiation has been linked to
skin cancer in humans and other adverse biological effects on plants and
animals. The dramatic ozone “hole” exists only over Antarctica, but currently,
the ozone layer over the United States is depleted by about 6 percent.
Temperature over the Antarctic
affects the formation of polar stratospheric clouds, which accelerate the
destruction of stratospheric ozone by human-produced chlorine and bromine
compounds. The Antarctic ozone hole is still expected to recover in about 50
years, when the atmospheric amounts of reactive chlorine and bromine return to
their pre-ozone-hole levels.
The observed size of the ozone
depletion region in 2003 is a stark contrast from 2002. The reduced size in 2002
was attributed to warmer-than-normal stratospheric temperatures and temperature
patterns above Antarctica. The size of this year’s Antarctic ozone hole reached
10.9 million square miles on Sept. 11, 2003, smaller than Sept. 10, 2000, the
largest ever recorded when it covered 11.5 million square miles. Last year the
ozone hole was smaller, covering 8.1 million square miles.
NOAA is dedicated to enhancing
economic security and national safety through the prediction and research of
weather and climate-related events and providing environmental stewardship of
the nation?s coastal and marine resources. NOAA is part of the U.S. Department
of Commerce.
Situation at
2003 May 30–British
Antarctic Survey Ozone Bulletin
Ozone values over
Antarctica have declined from the late spring peak and there are lower values
over the centre of the continent than over the southern ocean. Ozone values at
Halley have declined from the spring peak of 350 DU to around 240 DU. In
late May a mini ozone hole formed just off the continent and was located at 60°E
on May 28. Although temperatures are low enough for PSCs to form over the
continent, this feature is largely due to dynamical effects.
Environment Canada
Southern Hemisphere Ozone Map
Situation at 2003
July 21 –British
Antarctic Survey Ozone Bulletin
Ozone values over
Antarctica are already below 200 DU, with an ozone hole affecting most of the
continent. Temperatures in the ozone layer are low enough for PSCs to have
formed over the continent.
Environment Canada
Southern Hemisphere Ozone Map
http://exp-studies.tor.ec.gc.ca/cgi-bin/selectMap?lang=e
Situation at 2003
August 5 –British
Antarctic Survey Ozone Bulletin
Ozone values over
Antarctica are already below 200 DU, with an ozone hole affecting most of the
continent. Temperatures in the ozone layer are low enough for Polar
Stratospheric Clouds (PSCs) to have formed over the continent.
Environment Canada
Southern Hemisphere Ozone Map
http://exp-studies.tor.ec.gc.ca/cgi-bin/selectMap?lang=e
21August03-Large
ozone hole over Antarctica likely Scientists are predicting a large ozone hole
over much of Antarctica this spring.-
8/21/2003-Large
ozone hole over Antarctica likely
Situation at 2003 August 27-British
Antarctic Survey Ozone Bulletin
The ozone has grown rapidly and
now covers some 23 million square kilometres, larger than it has ever been at
this time in August. Very low ozone levels have been recorded over the
Antarctic Peninsula. Temperatures in the ozone layer are low enough that
Polar Stratospheric Clouds (PSCs) have formed widely over the continent.
Environment Canada
Southern Hemisphere Ozone Map
http://exp-studies.tor.ec.gc.ca/cgi-bin/selectMap?lang=e
Situation
at 2003 September 1–British
Antarctic Survey Ozone Bulletin–The
ozone has grown rapidly and now covers some 26 million square kilometres, larger
than it has ever been at this time in early September. Very low ozone
levels have been recorded over the Antarctic Peninsula. Temperatures in
the ozone layer are low enough that Polar Stratospheric Clouds (PSCs) have
formed widely over the continent.
Environment Canada
Southern Hemisphere Ozone Map
http://exp-studies.tor.ec.gc.ca/cgi-bin/selectMap?lang=e
Ozone Hole Reaches South America
7September03-The Ozone
hole has reached land and population areas in Argentina, Chile and The Falkland
Islands.
September 7,2003
Environment Canada
Southern Hemisphere Ozone Map
http://exp-studies.tor.ec.gc.ca/cgi-bin/selectMap?lang=e
The protective level of ozone has dropped below 200 dobson units in some areas.
Environment Canada
Southern Hemisphere Ozone Map
http://exp-studies.tor.ec.gc.ca/cgi-bin/selectMap?lang=e
Ozone levels are down as much as 50% in some areas.
Environment Canada
Southern Hemisphere Ozone Map
http://exp-studies.tor.ec.gc.ca/cgi-bin/selectMap?lang=e
Central Intelligence Agency Maps from University of Texas Map Center
The area and population affected including the Argentinean city of Ushaia which
has a population of 30,000 and Punta Arenas, Chile which has a population of
120,000 are all at risk during this time period.
The public should avoid going outside during the peak hours of 11:00 a.m. and
3:00 p.m. to avoid exposure to the UV rays. If people do go outside during these
hours they should wear protective sunscreen and if possible a hat or head
covering and sunglasses with a uv rating.
The Ozone hole has reached land and population areas in Argentina, Chile and The
Falkland Islands since the early 1990’s. Ozone levels drop down as much as 70%
in some areas. The protective level of ozone has dropped below 150 dobson units
in some areas.
It has reached further north at times affecting the towns of Rio Gallegos,
Puerto Santa Cruz, and Rio Grande affecting an additional 200,000 people.
Situation at 2003 September 9–British
Antarctic Survey Ozone Bulletin-The ozone has grown rapidly and now
covers some 28 million square kilometres, larger than it has ever been at this
time in early September. Very low ozone levels have been recorded over the
Antarctic Peninsula. Temperatures in the ozone layer are low enough that Polar
Stratospheric Clouds (PSCs), the key precursors to significant ozone depletion,
have formed widely over the continent.
Environment Canada
Southern Hemisphere Ozone Map
http://exp-studies.tor.ec.gc.ca/cgi-bin/selectMap?lang=e
Situation at 2003 September 12–British
Antarctic Survey Ozone Bulletin-The ozone has grown rapidly and now
covers some 27 million square kilometres, larger than it has ever been at this
time in early September. Very low ozone levels have been recorded over the
Antarctic Peninsula. The edge of the ozone hole touched the tip of South America
on September 6 – 7. Temperatures in the ozone layer are low enough that Polar
Stratospheric Clouds (PSCs), the key precursors to significant ozone depletion,
have formed widely over the continent and ozone levels are dropping quickly.
The British Antarctic Survey (BAS) Press release-Published:
12 Sep 2003 BA Festival of Science – The Ozone Hole 14.00 – 17.00. Lecture
Theatre B03, Peel Building, University of Salford Embargo – 09.30 hrs
12 September 2003 11 Sept 2003 PR No.9/2003
http://www.antarctica.ac.uk
Satellite observations (NOAA) suggest that this year’s ozone hole is so far one
of the biggest on record. The annual ‘hole’ has grown rapidly during August and
now covers some 27 million square kilometres, larger than it has ever been at
this time in early September. At the British Antarctic Survey’s Halley Research
Station ground-based ozone observations have commenced with the return of
sunlight. These initial values are around 40% down on those measured before the
ozone ‘hole’ and are comparable to those over the last decade. Speaking at the
British Association Annual Science Festival, Dr Alan Rodger of BAS said, “We
think we are turning the corner but we predict that it will be a decade or more
before we can say unambiguously that the ozone hole is recovering – assuming
that the decline in ozone depleting chemicals continues. Last year’s smaller
ozone hole should be regarded as exceptional and was clearly a one off event in
the record so far.”
Recent measurements at ground-based monitoring stations around the world show
that the loading of ozone destroying chemicals at the surface has been dropping
since about 1994 and is now about 6% down on that peak. The stratosphere, on the
other hand, lags behind the surface by several years and the loading of ozone
depleting chemicals in the ozone layer is at or near its peak. Satellite
measurements show that although the rate of decline in ozone amount in the upper
stratosphere is slowing, the total ozone amount is still declining.
Situation at 2003 September 16–British
Antarctic Survey Ozone Bulletin- The ozone has grown rapidly and is now
near its maximum size at around 26 million square kilometres (roughly twice the
size of Antarctica). It was larger than previously for the time of year in
August and early September, but is a little smaller than the all time record.
Very low ozone levels have been recorded over the Antarctic Peninsula. The edge
of the ozone hole touched the tip of South America on September 6 – 7.
Temperatures in the ozone layer are low enough that Polar Stratospheric Clouds
(PSCs), the key precursors to significant ozone depletion, have formed widely
over the continent and ozone levels are dropping quickly. The ozone hole is
usually largest in early September and deepest in late September to early
October. September 16 is world ozone day.
International Day for the Preservation of the Ozone Layer September 16-
On 19 December 1994, the United Nations General Assembly proclaimed 16 September
the International Day for the Preservation of the Ozone Layer, commemorating the
date, in 1987, on which the Montreal Protocol on Substances that Deplete the
Ozone Layer was signed (resolution 49/114). States are invited to devote the Day
each year to promote, at the national level, activities in accordance with the
objectives of the Montreal Protocol and its amendments. The following present
and past materials and information can be used by governments, industry and
individuals to help celebrate Ozone Day.
http://www.unep.org/ozone/ozone_day2003/index.shtml
Situation at 2003 September 22–British
Antarctic Survey Ozone Bulletin- The ozone hole has grown rapidly and
peaked in size at around 28 million square kilometres (roughly twice the size of
Antarctica) in mid September. It was larger than previously for the time of year
in August and early September, but the maximum size only equalled the all time
record. Very low ozone levels have been recorded over the Antarctic Peninsula.
The edge of the ozone hole touched the tip of South America on September 6 – 7.
Temperatures in the ozone layer are low enough that Polar Stratospheric Clouds
(PSCs), the key precursors to significant ozone depletion, have formed widely
over the continent and ozone levels are dropping quickly. The ozone hole is
usually largest in early September and deepest in late September to early
October.
9/22/2003-Media
release: 22 September 2003
| Antarctic ozone hole – near record levels | Measurements by National Institute
of Water & Atmospheric Research (NIWA) staff at Scott Base, Antarctica-
Antarctic ozone hole – near record levels
Situation at 2003 September 25–British
Antarctic Survey Ozone Bulletin- Temperatures in the ozone layer
are low enough that Polar Stratospheric Clouds (PSCs), the key precursors to
significant ozone depletion, have formed widely over the continent. Ozone levels
dropped quickly during August and September with the return of sunlight and
depletion exceeds 55% in places. The ozone hole grew rapidly and peaked in size
at around 28 million square kilometres (roughly twice the size of Antarctica) in
mid September. It was larger than previously for the time of year in August and
early September, but the maximum size only equalled the all time record. Ozone
sonde flights from Rothera show substantial depletion between 12 and 23
kilometres, with effectively 100% depletion at times at some altitudes.
25September3-2003
Ozone ‘Hole’ Approaches, But Falls Short of Record
This year’s Antarctic ozone hole is the second largest ever observed, according
to scientists from NASA, the National Oceanic and Atmospheric Administration
(NOAA), and the Naval Research Laboratory (NRL). Full
Story Click here
29September03-The Ozone
hole has again reached land and population areas in Argentina, Chile and The
Falkland Islands.
Central Intelligence Agency Maps from University of Texas Map Center
The protective level of ozone has dropped below 200 dobson units in some areas.
Environment Canada
Southern Hemisphere Ozone Map 9/29/03
http://exp-studies.tor.ec.gc.ca/cgi-bin/selectMap?lang=e
The area and population affected are the Argentinean city of Ushaia which has a
population of 30,000 and Punta Arenas, Chile which has a population of 120,000
and the towns of Rio Gallegos, Puerto Santa Cruz, and Rio Grande affecting an
additional 200,000 people .
Environment Canada
Southern Hemisphere Ozone Map 9/30/03
http://exp-studies.tor.ec.gc.ca/cgi-bin/selectMap?lang=e
The public should avoid going outside during the peak hours of 11:00 a.m. and
3:00 p.m. to avoid exposure to the UV rays. If people do go outside during these
hours they should wear protective sunscreen and if possible a hat or head
covering and sunglasses with a uv rating.
The Ozone hole has reached land and population areas in Argentina, Chile and The
Falkland Islands since the early 1990’s. Ozone levels drop down as much as 70%
in some areas. The protective level of ozone has dropped below 150 dobson units
in some areas.
Situation at 2003 October 1
British Antarctic Survey Ozone Bulletin-
Temperatures in the ozone layer remain low enough that Polar Stratospheric
Clouds (PSCs), the key precursors to significant ozone depletion, exist widely
over the continent. Ozone levels dropped quickly during August and September
with the return of sunlight and depletion now exceeds 60% in places with small
areas registering below 100 DU. The ozone hole grew rapidly and peaked in size
at around 28 million square kilometres (roughly twice the size of Antarctica) in
mid September. It was larger than previously for the time of year in August and
early September, but the maximum size only equalled the all time record. Ozone
sonde flights from Rothera show substantial depletion between 12 and 24
kilometres, with 100% depletion at times at some altitudes. The edge of the
ozone hole touched the tip of South America and the Falkland Islands over
September 27 – 30.
08October03-The Ozone
hole has again reached land and population areas in Argentina, Chile and The
Falkland Islands.
Environment Canada
Southern Hemisphere Ozone Map 10/04/03
http://exp-studies.tor.ec.gc.ca/cgi-bin/selectMap?lang=e
The protective level of ozone has dropped below 200 dobson units in some areas.
Environment Canada
Southern Hemisphere Ozone Map 10/05/03
http://exp-studies.tor.ec.gc.ca/cgi-bin/selectMap?lang=e
Environment Canada
Southern Hemisphere Ozone Map 10/06/03
http://exp-studies.tor.ec.gc.ca/cgi-bin/selectMap?lang=e
Environment Canada
Southern Hemisphere Ozone Map 10/07/03
http://exp-studies.tor.ec.gc.ca/cgi-bin/selectMap?lang=e
The public should avoid going outside during the peak hours of 11:00 a.m. and
3:00 p.m. to avoid exposure to the UV rays. If people do go outside during these
hours they should wear protective sunscreen and if possible a hat or head
covering and sunglasses with a uv rating.
Environment Canada
Southern Hemisphere Ozone Map 10/08/03
http://exp-studies.tor.ec.gc.ca/cgi-bin/selectMap?lang=e
Situation at 2003 October 8
British Antarctic Survey Ozone Bulletin-
Temperatures in the ozone layer remain low enough that Polar Stratospheric
Clouds (PSCs), the key precursors to significant ozone depletion, still exist
widely over the continent. The centre of the ozone hole is significantly offset
from the pole and is currently over Halley station. The tip of South America and
the Falkland Islands suffered significant ozone depletion over October 4 – 8
WMO Antarctic Ozone Bulletin Issued on 16 October 2003
The polar vortex has decreased in area by about 10%from the maximum size it
reached in September,and is now about 31 million square kilometres (M km 2 ).The
vortex is nearly circular and centred over the pole at the lower
altitudes,although more elongated and skewed toward the Atlantic Ocean at
altitudes of 20 km and above.Typical daily minimum stratospheric temperatures
over Antarctica have continued to increase in the past two weeks,but are still
sufficiently cold to produce polar stratospheric clouds (PSCs)over about 10 M km
2 of the lower vortex.This represents a significant warming from the 25 M km 2
PSC area reported for late September which will ultimately result in a decrease
in ozone loss during the coming weeks.
As is usual,the area of the ozone hole decreased during the first two weeks of
October,including a sharp decrease to less than18 M km 2 that occurred during
the second week.This area is much smaller than the near record size of 28 M km 2
observed during late September.The city of Ushuaia,Argentina, located on the
southern tip of South America,has been under the ozone hole on four occasions
this year. On 6 October, column ozone decreased to nearly 60%below norms
resulting in very high UV levels,with a maximum measured UV Index of more than
9.While typical maximum UV Index values for this time of the year in Ushuaia are
between 3 and 5,on one occasion in October 2000,an Index of 11 was observed when
the ozone hole was also overhead and there were cloud free conditions.
Situation at 2003 October 23
British Antarctic Survey Ozone Bulletin-
Temperatures in the ozone layer still remain low enough for Polar Stratospheric
Clouds (PSCs), the key precursors to significant ozone depletion, to exist in
some places over the continent. Temperatures are however rising quickly. The
centre of the ozone hole is significantly offset from the pole and is currently
over Halley station and extended into the Atlantic Ocean.
Environment Canada
Southern Hemisphere Ozone Map 10/26/03
http://exp-studies.tor.ec.gc.ca/cgi-bin/selectMap?lang=e
Situation at 2003 October
31
British Antarctic Survey Ozone Bulletin-Temperatures
in the ozone layer are generally now near the limit for Polar Stratospheric
Clouds (PSCs), the key precursors to significant ozone depletion, to exist over
the continent. Temperatures are rising quickly. The centre of the ozone hole is
significantly offset from the pole and is currently over East Antarctica. The
tip of South America and the Falkland Islands suffered significant ozone
depletion over October 4 – 9.
Situation at 2003 November 6
British Antarctic Survey Ozone Bulletin-
Temperatures in the ozone layer are rising quickly and are generally above the
limit for Polar Stratospheric Clouds (PSCs), the key precursors to significant
ozone depletion, to exist over the continent. The ozone hole is filling in and
now covers less than 10 million square kilometres. The centre of the ozone hole
is significantly offset from the pole and is currently over East Antarctica.
Environment Canada
Southern Hemisphere Ozone Map
http://exp-studies.tor.ec.gc.ca/cgi-bin/selectMap?lang=e
Situation at 2003 November13
British Antarctic Survey Ozone Bulletin-
Temperatures in the ozone layer have risen quickly and are above the limit for
Polar Stratospheric Clouds (PSCs), the key precursors to significant ozone
depletion, to exist over the continent. The ozone hole is filling in and now
covers less than 5 million square kilometres. Forecasts suggest that it will
completely fill in over the next week.
Environment Canada
Southern Hemisphere Ozone Map
http://exp-studies.tor.ec.gc.ca/cgi-bin/selectMap?lang=e
WMO Antarctic Ozone Bulletin Issued on 20 November 2003-The
ozone hole continued its October decrease from its maximum size of 28 M km 2
reached in late September,and finally disappeared during the past few days.The
ozone hole size and persistence have developed similarly to the year 2000,with
an early rapid growth observed during August,a record size observed in September
and finally its disappearance in mid November.The rapid decrease in the size of
the ozone hole during October and November apparently is a result of the ozone
depleted air within the hole being gradually replaced by or diluted by ozone
rich air from outside.The ozone hole has now disappeared,however the vortex
remains intact although significantly smaller and weaker.Additionally,the ozone
mass deficit,a measure of the depth of the ozone hole,is 30-50%of its maximum
value reached in September.Column ozone has remained normal for November in the
city of Ushuaia,Argentina,located on the southern tip of South America,and has
not been under the ozone hole since early October.UV levels measured at Ushuaia
and the Antarctic stations of McMurdo,Palmer,and South Pole were all below the
long-term mean for those locations.
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