[Vision2020] New NASA Supported Data: Unprecedented 2011 Arctic Ozone Loss: Stratospheric Cooling From Anthropogenic Greenhouse Gas Impacts?

[Ted Moffett]

As is well known to anyone studying climate science, one of the unique
signatures of increasing anthropogenic greenhouse gas warming of our
atmosphere is tropospheric warming, coupled with stratospheric cooling.
Read on this subject here:
http://www2.sunysuffolk.edu/mandias/global_warming/smoking_gun_humans_climate_change.html

"Tropospheric warming with stratospheric
cooling<http://www2.sunysuffolk.edu/mandias/global_warming/greenhouse_gases.html#stratospheric_cooling>is
essentially another "smoking gun" for anthropogenic global warming.
There
are no known natural forcing mechanisms that result in this coupling. Solar
forcing, cloud cover, ENSO, PDO, NAO, etc. cannot explain a cooler
stratosphere even when ozone depletion is accounted for. Increasing
greenhouse gases explain this coupling very well and climate models predict
a warmer troposphere and a cooler stratosphere with increased greenhouse
gases. "

-----------------------------------
I don't want to oversimplify, but my understanding is that as more thermal
energy is trapped in the troposphere from increasing CO2 levels, less heat
escapes to higher levels of the atmosphere, cooling the stratosphere.

This new NASA supported study, published Oct. 2, 2011 in the journal Nature,
indicates that an unusually cold Arctic stratosphere lasting into spring in
2011 was a factor in causing the low ozone level measured in 2011.  The
article below states:

"This implies that if winter Arctic stratospheric temperatures drop just
slightly in the future, for example as a result of climate change, then
severe Arctic ozone loss may occur more frequently."
---------------------------------
NASA Leads Study of Unprecedented Arctic Ozone Loss

http://www.jpl.nasa.gov/news/news.cfm?release=2011-308&rn=news.xml&rst=3158

October 02, 2011

PASADENA, Calif. - A NASA-led study has documented an unprecedented
depletion of Earth's protective ozone layer above the Arctic last winter and
spring caused by an unusually prolonged period of extremely low temperatures
in the stratosphere.

The study, published online Sunday, Oct. 2, in the journal Nature, finds the
amount of ozone destroyed in the Arctic in 2011 was comparable to that seen
in some years in the Antarctic, where an ozone "hole" has formed each spring
since the mid-1980s. The stratospheric ozone layer, extending from about 10
to 20 miles (15 to 35 kilometers) above the surface, protects life on Earth
from the sun's harmful ultraviolet rays.

The Antarctic ozone hole forms when extremely cold conditions, common in the
winter Antarctic stratosphere, trigger reactions that convert atmospheric
chlorine from human-produced chemicals into forms that destroy ozone. The
same ozone-loss processes occur each winter in the Arctic. However, the
generally warmer stratospheric conditions there limit the area affected and
the time frame during which the chemical reactions occur, resulting in far
less ozone loss in most years in the Arctic than in the Antarctic.

To investigate the 2011 Arctic ozone loss, scientists from 19 institutions
in nine countries (United States, Germany, The Netherlands, Canada, Russia,
Finland, Denmark, Japan and Spain) analyzed a comprehensive set of
measurements. These included daily global observations of trace gases and
clouds from NASA's Aura and CALIPSO spacecraft; ozone measured by
instrumented balloons; meteorological data and atmospheric models. The
scientists found that at some altitudes, the cold period in the Arctic
lasted more than 30 days longer in 2011 than in any previously studied
Arctic winter, leading to the unprecedented ozone loss. Further studies are
needed to determine what factors caused the cold period to last so long.

"Day-to-day temperatures in the 2010-11 Arctic winter did not reach lower
values than in previous cold Arctic winters," said lead author Gloria Manney
of NASA's Jet Propulsion Laboratory in Pasadena, Calif., and the New Mexico
Institute of Mining and Technology in Socorro. "The difference from previous
winters is that temperatures were low enough to produce ozone-destroying
forms of chlorine for a much longer time. This implies that if winter Arctic
stratospheric temperatures drop just slightly in the future, for example as
a result of climate change, then severe Arctic ozone loss may occur more
frequently."

The 2011 Arctic ozone loss occurred over an area considerably smaller than
that of the Antarctic ozone holes. This is because the Arctic polar vortex,
a persistent large-scale cyclone within which the ozone loss takes place,
was about 40 percent smaller than a typical Antarctic vortex. While smaller
and shorter-lived than its Antarctic counterpart, the Arctic polar vortex is
more mobile, often moving over densely populated northern regions. Decreases
in overhead ozone lead to increases in surface ultraviolet radiation, which
are known to have adverse effects on humans and other life forms.

Although the total amount of Arctic ozone measured was much more than twice
that typically seen in an Antarctic spring, the amount destroyed was
comparable to that in some previous Antarctic ozone holes. This is because
ozone levels at the beginning of Arctic winter are typically much greater
than those at the beginning of Antarctic winter.

Manney said that without the 1989 Montreal Protocol, an international treaty
limiting production of ozone-depleting substances, chlorine levels already
would be so high that an Arctic ozone hole would form every spring. The long
atmospheric lifetimes of ozone-depleting chemicals already in the atmosphere
mean that Antarctic ozone holes, and the possibility of future severe Arctic
ozone loss, will continue for decades.

"Our ability to quantify polar ozone loss and associated processes will be
reduced in the future when NASA's Aura and CALIPSO spacecraft, whose trace
gas and cloud measurements were central to this study, reach the end of
their operational lifetimes," Manney said. "It is imperative that this
capability be maintained if we are to reliably predict future ozone loss in
a changing climate."

Other institutions participating in the study included Alfred Wegener
Institute for Polar and Marine Research, Potsdam, Germany; NASA Langley
Research Center, Hampton, Va.; Royal Netherlands Meteorological Institute,
De Bilt, The Netherlands; Delft University of Technology, 2600 GA Delft, The
Netherlands; Science Systems and Applications, Inc., Greenbelt, Md., and
Hampton, Va.; Science and Technology Corporation, Lanham, Md.; Environment
Canada, Toronto, Ontario, Canada; Central Aerological Observatory, Russia;
NOAA Earth System Research Laboratory, Boulder, Colo.; Arctic Research
Center, Finnish Meteorological Institute, Finland; Danish Climate Center,
Danish Meteorological Institute, Denmark; Eindhoven University of
Technology, Eindhoven, The Netherlands; Arctic and Antarctic Research
Institute, St. Petersburg, Russia; National Institute for Environmental
Studies, Japan; National Institute for Aerospace Technology, Spain; and
University of Toronto, Ontario, Canada.

For more information on NASA's Aura mission, visit:
http://www.nasa.gov/aura. For more information on NASA's CALIPSO
mission, visit:
http://www.nasa.gov/calipso .

JPL is managed for NASA by the California Institute of Technology in
Pasadena.

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Vision2020 Post: Ted Moffett
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