I
have a real problem accepting the linkage between the Ozone hole
first revealed thirty years ago and linked to CFC’s mostly because
we have absolutely no comparable data much before
that. And off
course the climate has changed from what is known of the past and the
linkage is then inferred and accepted.
No
mention is made of the sharp increase in cosmic rays through the hole
that acts as a natural seeder of precipitation. Lack of ozone should
make that process increase sharply.
Much
more interesting is that the Southern Hemisphere has reached record
ice levels nicely conforming to my millennial circumpolar conjecture
discussed in earlier posts. It will be interesting now to see just
how long this is maintained.
Why
does the area over southern high and sub tropical latitudes have more
frequent and stronger rains?
by
Staff Writers
Ulsan, Korea (SPX) Sep 09, 2013
The
new study by Prof. Sarah Kang from Ulsan National Institute of
Science and Technology (UNIST), showed that the ozone depletion over
the South Pole has affected the extreme daily precipitation in the
austral summer, for December, January, and February (DJF). This work
was published in the journal Geophysical Research Letter. (Title:
"Modeling evidence that ozone depletion has impacted extreme
precipitation in the austral summer", Vol. 40, 1-6,
doi:10.1002/grl.50796, 2013)
The
ozone hole over the Antarctic has affected atmospheric circulation in
the Southern Hemisphere (SH) summer and Kang's previous article in
Science, analyzed the impact of ozone depletion to increased rainfall
in the subtropics.
The
new article is explaining about the impact of stratospheric ozone
depletion on the extreme daily precipitation in the austral summer
with two global climate models: the Canadian middle Atmosphere Model
(CMAM) and the National Center for Atmospheric Research Community
Atmospheric Mode (CAM3).
This
research study has also been highlighted in the journal Nature
Geoscience in September.
The
research team led by Prof. Kang focused on a carefully conceived set
of multimodel integrations forced only with observed stratospheric
ozone changes. This single-forcing approach allows the research team
to show extremes, in response to stratospheric ozone depletion and
that these changes are likely of a dynamic rather than thermodynamic
nature.
The
ozone layer is a layer in the Earth's atmosphere which absorbs most
of the UV radiation and contains relatively high concentrations of
ozone (O3). This ozone layer had been broken by the widespread use of
man-made compounds containing chlorofluorocarbons (CFCs). After the
discovery of the ozone hole, 1989 Montreal Protocol signed by 196
countries to reduce global CFC production to protect the ozone hole.
In
this research they discovered that the ozone depletion in the
Antarctic area is associated with extreme rain in the austral summer
and it would be used to forecast heavy rain and the natural disasters
in the future.
Dangerous
floods have occurred in every Australian state over the last 150
years. Some caused great loss of life, others devastated
infrastructure. Between 1852 and 2011 at least 951 people were killed
by floods, another 1326 were injured, and the cost of damage reached
an estimated $4.76 million dollars.
Even
though we can predict these natural disasters in advance, we can't
stop the flood but we can be prepared for it and reduce the damage.
"Due
to limited data availability in the SH, it is hard to robustly
determine observed changes in extreme precipitation," said Prof.
Kang. "However, since the recent Southern Hemisphere climate
change is driven by the ozone hole, we can deduce the recent trend
from our climate model integrations."
"We
would expand our research to see the correlation of the ozone
depletion of the North Pole and the climate changes in the Northern
Hemisphere," said Prof. Kang, showing her future research plan.
*Extreme
daily precipitation- The strong precipitation that would happen with
1% probability.
This
research was supported by the 2013 Creativity and Innovation Research
Fund 1.130033 of UNIST (Ulsan National Institute of Science and
Technology). Fellow authors include: L.M. Polvani and G.J.P. Correa
from Columbia University, J.C. Fyfe and M. Sigmond from Canadian
Centre for Climate Modelling and Analysis, Environment Canada and
S.-W. Son from Seoul National University, Korea.
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