Here's some more science to be politicized and ignored until some
billionaire's child dies of melanoma from the beach at the Hamptons.
It's a GOP cancer cell.   I wonder how the elephants out of doors in Africa
will tolerate the sun?

 

REH

 

 

 

July 26, 2012 Science Times


Storms Threaten Ozone Layer Over U.S., Study Says


By
<http://topics.nytimes.com/top/reference/timestopics/people/f/henry_fountain
/index.html> HENRY FOUNTAIN


Strong summer storms that pump water high into the upper atmosphere pose a
threat to the protective ozone layer over the United States, researchers
said on Thursday, adding that the risk of damage may increase as the climate
warms.

In a study
<http://www.sciencemag.org/content/early/2012/07/25/science.1222978>
published online by the journal Science, Harvard University scientists
reported that some storms send water vapor well into the stratosphere -
which is normally drier than a desert - and showed how such events could
rapidly set off ozone-destroying reactions with chemicals that remain in the
atmosphere from CFCs, the now-banned refrigerant gases.

Ozone helps shield people, animals and crops from damaging ultraviolet rays
from the sun. Much of the concern about the ozone layer has focused on
Antarctica, where a seasonal hole, or thinning, has been seen for two
decades, and the Arctic, where a hole was observed last year. But those
regions have almost no population.

A thinning of the ozone layer over the United States during summers could
mean an increase in ultraviolet exposure for millions of people and a rise
in the incidence of skin cancer, the researchers said.

"This problem now is of deep concern to me," said James G. Anderson, an
atmospheric scientist and the lead author of the study. "I never would have
suspected this."

The findings were based on sound science, he and other experts said, but
direct measurements of the impact of water vapor on ozone chemistry are
lacking, and much more research is needed.

While there is conclusive evidence that strong storms have sent water vapor
as high as 12 miles - through a process called convective injection - and
while climate scientists say one effect of
<http://topics.nytimes.com/top/news/science/topics/globalwarming/index.html?
inline=nyt-classifier> global warming is an increase in the intensity and
frequency of storms, it is not yet clear if the number of such injection
events will rise.

"Nobody understands why this convection can penetrate as deeply as it does,"
said Dr. Anderson, who has studied the atmosphere for four decades.

"It's the union between ozone loss and climate change that is really at the
heart of this," he said, adding that for years he and other scientists had
always been careful to keep the two concepts separate. "Now, they're
intimately connected."

Mario J. Molina, a co-recipient of a
<http://topics.nytimes.com/top/news/science/topics/nobel_prizes/index.html?i
nline=nyt-classifier> Nobel Prize for research in the 1970s that uncovered
the link between CFCs and damage to the ozone layer, said the study added
"one more worry to the changes that society's making to the chemical
composition of the atmosphere." Dr. Molina, who was not involved in the
work, said the concern was "significant ozone depletion at latitudes where
there is a lot of population, in contrast to over the poles."

The study, which was financed by the National Aeronautics and Space
Administration, focused on the United States because that is where the data
was collected. But the researchers pointed out that similar conditions could
exist at other midlatitude regions.

Ralph J. Cicerone, an atmospheric scientist and the president of the
National Academy of Sciences, who reviewed the study for Science, also
called for more research. "One of the really solid parts of this paper is
that they've taken the chemistry that we know from other atmospheric
experiments and lab experiments and put that in the picture," he said. "The
thing to do is do field work now - measure moisture amounts and whether
there is any impact around it."

"The connection with future climate is the most important issue," Dr.
Cicerone said.

Large thunderstorms of the type that occur from the Rockies to the East
Coast and over the Atlantic Ocean produce updrafts, as warm moist air
accelerates upward and condenses, releasing more heat. In most cases, the
updrafts stop at a boundary layer between the lower atmosphere and the
stratosphere called the tropopause, often producing flat-topped clouds that
resemble anvils. But if there is enough energy in a storm, the updraft can
continue on its own momentum, punching through the tropopause and entering
the stratosphere, said Kerry Emanuel, an atmospheric scientist at the
Massachusetts Institute of Technology.

When Dr. Anderson produced data about five years ago clearly showing these
strong injections of water vapor, "I didn't believe it at first," Dr.
Emanuel said. "But we've come to see that the evidence is pretty strong that
we do get them."

At the same time, he added, "we don't really understand what determines the
potential for convection in the atmosphere," so it is difficult to say what
the effect of climate change will be.

"We're much further along on understanding how
<http://topics.nytimes.com/top/reference/timestopics/subjects/h/hurricanes_a
nd_tropical_storms/index.html?inline=nyt-classifier> hurricanes respond to
climate change than normal storms," Dr. Emanuel said.

CFCs, or chlorofluorocarbons, were banned in the mid-1980s by the
international treaty called the Montreal Protocol, but it will take decades
for them to be cleansed fully from the atmosphere. It is chlorine from the
CFCs that ultimately destroys ozone, upsetting what is normally a balanced
system of ozone creation and decay. The chlorine has to undergo a chemical
shift in the presence of sunlight that makes it more reactive, and this
shift is sensitive to temperature.

Dr. Anderson and his colleagues found that a significant concentration of
water vapor raises the air temperature enough in the immediate vicinity to
allow the chemical shift, and the ozone-destroying process, to proceed
rapidly.

"The rate of these reactions was shocking to us," Dr. Anderson said. "It's
chemistry that was sitting there, waiting to be revealed."

Dr. Anderson said that if climate change led to more events in which water
was injected well into the stratosphere, the effect on ozone could not be
halted. "Because it's linked to the inexorable addition of CO2 and methane,"
he said, "it's irreversible."

If CFCs had not been banned, the ozone layer would be in far worse shape
than it is. But by showing that CFC-related ozone destruction can occur in
conditions other than the cold ones at the poles, the study suggests that
the full recovery of the ozone layer may be further off than previously
considered.

"The world said, 'Oh, we've controlled the source of CFCs; we can move on to
something else,' " Dr. Anderson said. "But the destruction of ozone is far
more sensitive to water vapor and temperature."

 

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