that existing aircraft could be modified to lift
huge quantities of sulphur dioxide to great
heights, and then release it. “Dozens of countries could fund such a
programme, and the required technology is
not particularly exotic.”
“Turns out that is not so,” he said. “It would
indeed take an entirely new plane design
to do SAI under reasonable albeit entirely
hypothetical parameters. No existing aircraft
has the combination of altitude and payload
capabilities required.” Political tensions
But solar radiation management or SRM – the
catch-all term for any plans to cool the world
by dimming the sunlight, rather than reducing
greenhouse gas emissions – remains politically
fraught, and in any case an incomplete
answer: it would, for instance, do nothing to
slow the increasing acidification of the world’s
oceans, and it could seriously affect rainfall
patterns in so far unpredictable ways.
Detailed design
The scientists outlined a solution: it had the
same weight as a large, narrow-bodied jet
passenger aircraft. But to sustain level flight
at 20kms, it needed roughly double the wing
surface of such an airliner, and double the
thrust, with four engines rather than two. “At
the same time, its fuselage would be stubby
and narrow, sized to accommodate a heavy
but dense mass of molten sulphur rather than
the large volume of space and air required for
passengers,” Mr Smith said.
They then calculated the rate at which such
planes could be built, and the numbers
needed to make a significant difference to
global warming. Global projects on such a
scale need international agreement, and
the two authors rule out the possibility that
any individual nation could hope to secretly
operate such a high-flying programme,
involving so many flights, without detection.
But they do not see it as excessively costly.
“Given the potential benefits of halving
average projected increases to radiative
forcing from a particular date onward, these
numbers invoke the ‘incredible economics’
of solar geoengineering,” Dr Wagner said.
AgriKultuur |AgriCulture
The world has already warmed by 1°C in
the last century. In Paris in 2015 the nations
of almost the entire world agreed to try
to contain global warming to 1.5°C if at all
possible. And the world now has only about a
dozen years to make this happen.
“Why then set out a plan to implement solar
radiation management from a date 15 years
hence? This plan is a distraction that may
well encourage weaker action on emissions
reduction by governments in the hope they
will no longer be necessary”, said Joanna
Haigh, co-director of the Grantham Institute
for Climate Change at Imperial College in the
UK.
“Previously, proponents of SRM have
suggested that it be used to delay the
onset of the inevitable warming arising
from human greenhouse gas emissions.
This paper, however, seems to suggest that
the implementation should be ongoing.
Forever?” – Climate News Network info@
climatenewsnetwork.net
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