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<DIV style="FONT-SIZE: 12pt; FONT-FAMILY: 'Calibri'; COLOR: #000000"><FONT
face="Times New Roman">New light-reflecting particles could cool Earth and fix
the ozone layer <BR>====================== <BR>Honouring the commitments
made at last year's historic Paris climate <BR>deal will take a huge
international effort to lower carbon emissions - <BR>but scientists say there's
another way we can help reduce rising global <BR>temperatures at the same
time. <BR> <BR>In a process called solar geoengineering,
light-reflecting particles <BR>could be introduced into Earth's stratosphere to
bounce the Sun's rays <BR>back into space and keep the planet cooler. While this
controversial <BR>concept has been discussed for decades, the risks of
geoengineering have <BR>kept the research largely sidelined - but now
researchers say they might <BR>have a way of making it safe. <BR>
<BR>Solar geoengineering usually refers to dispersing sulphate aerosols into
<BR>the stratosphere. This naturally occurs during volcanic explosions,
<BR>where the particles reflect sunlight and have a cooling effect on the
<BR>planet. But the problem with sulphate aerosols is that they produce
<BR>sulphuric acid in the stratosphere, which damages the ozone layer.
<BR> <BR>But now, looking for particles capable of neutralising sulphuric,
<BR>nitric, and hydrochloric acid on their surface, researchers from Harvard
<BR>University discovered that calcite was what they needed, as it can
<BR>convert the acids into stable salts. Mimicking stratospheric conditions
<BR>in lab experiments, the team says that calcite can indeed reflect light
<BR>while countering ozone loss - and its abundance on Earth would also make
<BR>it a practical resource for geoengineering. <BR> <BR>But despite
the promising new lead, the team says a huge amount of <BR>additional research
needs to be done. The potential dangers of a botched <BR>geoengineering
endeavour aren't to be understated - it even ranked as a <BR>high-risk
environmental threat on a list of global catastrophic risks <BR>published
earlier this year. <BR><BR>Science Alert - December 14, 2016 <BR> </FONT><A
style='href: "http://www.merit.unu.edu/itweekly/ref.php?nid=5791"'><FONT
face="Times New Roman">http://www.merit.unu.edu/itweekly/ref.php?nid=5791</FONT></A><FONT
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