Wed 4 Nov
2009
Can we manipulate the weather?
Chinese scientists claim to be able to control the
weather. But is so-called geoengineering more than wishful thinking? And, if
so, should we be worried?
David Adam
Wed 4 Nov 2009 00.05 GMT
https://www.theguardian.com/environment/2009/nov/04/controlling-the-weather-china
The unseasonal snow that fell on Beijing for 11 hours
on Sunday was the earliest and heaviest there has been for years. It was also,
China claims, man-made. By the end of last month, farmland in the already dry
north of China was suffering badly due to drought. So on Saturday night China's
meteorologists fired 186 explosive rockets loaded with chemicals to "seed"
clouds and encourage snow to fall. "We won't miss any opportunity of
artificial precipitation since Beijing is suffering from a lingering
drought," Zhang Qiang, head of the Beijing Weather Modification Office,
told state media.
The US has tinkered with such cloud seeding to
increase water flow from the Sierra Nevada mountains in California since the
1950s, but there remains widespread scientific sniffiness in the west at such
attempts at weather control. The chemicals fired into the sky, usually dry ice
or silver iodide, are supposed to provide a surface for water vapour to form
liquid rain. But there is little evidence that it works – after all, how do
investigating scientists know it would not have rained anyway?
Such doubts have not stopped China claiming mastery
over the clouds. Officials said the blue skies that brightened Beijing's parade
to celebrate 60 years of communism last month were a result of the 18
cloud-seeding jets and 432 explosive rockets scrambled to empty the sky of rain
beforehand. Last year, more than 1,000 rockets were fired to ensure a dry night
for last year's Olympic opening ceremony.
"Only a handful of countries in the world could
organise such large-scale, magic-like weather modification," Cui Lianqing,
a senior meteorologist with the Chinese air force, told the Xinhua news agency
after last month's parade.
Magic or not, there is growing interest in such
attempts to deliberately steer the weather, and on a much larger scale. Next
spring, a group of the world's leading experts on climate change will gather in
California to plan how it could be done as a way to tackle global warming, and
by whom. The ideas, some of which, similar to cloud-seeding, involve firing
massive amounts of chemicals into the atmosphere, can sound far-fetched, but
they are racing up the agenda as pessimism grows about the likely course of
global warming.
As interest grows, so does concern about whether such
techniques, known as geoengineering, could be developed and unleashed by a
single nation, or even a wealthy individual, without wide international
approval. "What will happen when Richard Branson decides he really does
want to save the planet?" asks one climate expert. If China thinks it can
make cloud seeding work, then what about geoengineering?
"If climate change turns ugly, then many
countries will start looking at desperate measures," says David Victor, an
energy policy expert at Stanford University and a senior fellow at the Council
on Foreign Relations. "Logic points to a big risk of unilateral
geoengineering. Unlike controlling emissions, which requires collective action,
most highly capable nations could deploy geoengineering systems on their
own."
Victor is a heavyweight policy analyst, but one of his
most impressive academic feats could have been to smuggle the name of the
world's favourite secret agent into the sober pages of the Oxford Review of
Economic Policy. "Geoengineering may not require any collective
international effort to have an impact on climate," he wrote in an article
published last year. "A lone Greenfinger, self-appointed protector of the
planet and working with a small fraction of the [Bill] Gates bank account,
could force a lot of geoengineering on his own. Bond films of the future might
[enjoy incorporating] the dilemma of unilateral planetary engineering."
Move over, Goldfinger.
Unilateral geoengineering worries experts for two
reasons. First, the massive side effects; what it could do to the world's
rainfall, for example. Second, once started, geoengineering would probably have
to be continued, as stopping could bring an abrupt change in climate. "One
of the many dangers with unilateral geoengineering is that once a country
starts, it becomes very hard to stop," Victor says. "Removing a warming
mask, even if it is a flawed mask, would expose the planet to even more rapid
and probably dangerous warming."
In a world where action on global warming has created
new markets in carbon worth billions of pounds, countries are not the only
players. Geoengineering would require investment and the private sector is
already eyeing up opportunities. Two companies have emerged with a business
plan based on dumping iron in the sea and then selling carbon offsets based on
the extra pollution supposedly soaked up by the resulting algal bloom. And in
their new book, Superfreakonomics, Steven Levitt and Stephen Dubner talk approvingly
of Nathan Myhrvold, the former chief technology officer of Microsoft, whose
company, Intellectual Ventures, is exploring the possibility of pumping large
quantities of reflective sulphur dust into the Earth's stratosphere through a
patented 18-mile-long hose held up by helium balloons.
This is the point where most people will shake their
heads, say the whole silly idea will never happen, and skip to the crossword.
They could be right, but the global warming story has a tendency to outpace
most attempts to predict its path. Just a few years ago, scientists and
politicians talked of the need to avoid a 2C rise in global temperature, yet
experts recently gathered at an Oxford University conference openly talked of a
likely 4C rise, which, without urgent and unlikely action, a new report from
the Met Office says could come within many of our lifetimes.
A decade ago, an unproven idea called carbon
sequestration, that would see carbon emissions from power stations trapped
under the ground, was talked up by a small group of advocates, but was
dismissed by most people as too expensive and unworkable on a large scale.
Renamed carbon capture and storage, the idea is now mainstream energy policy in
countries including Britain, despite still being unproven and dismissed by many
as too expensive and unworkable on a large scale. Last month, the International
Energy Agency said the world should build 100 full-scale carbon-capture power
stations by 2020, and 850 by 2030.
If the geoengineering narrative follows a similar arc,
then how long until nations or individuals that have the most to lose, or are
the first to accept that the required massive emission cuts are impossible,
turn to the presently unthinkable option? The US government, under President
Bush, has already lobbied the Intergovernmental Panel on Climate Change to
promote geoengineering research as "insurance". When the Royal
Society recently carried out an investigation of the options, senior figures
privately expected it to dismiss the whole concept as nonsense. Instead the
society, Britain's premier scientific academy, concluded in September that
methods to block out the sun "may provide a potentially useful short-term
backup to mitigation in case rapid reductions in global temperature are
needed". The society stressed that emissions reductions were the way to
go, but recommended international research and development of the "more
promising" geoengineering techniques.
"My guess is that we will be taking
geoengineering a lot more seriously in the next decade," says Victor,
"but we won't be in a position to deploy systems for some time. Most
nations will decide it is needed only if we have really bad luck as warming
unfolds and if we fail miserably in controlling emissions. I put the odds of
using such systems in the next 40 years at perhaps one in five."
Of all the apparent obstacles to geoengineering, cost
is not likely to be among them. Compared with the expense of investing in
renewable energy and phasing out fossil fuels, the cheapest geoengineering
options come with a price tag of just a few billion pounds, perhaps 1% of what
it could cost to tackle global warming through emissions cuts.
Alan Robock, an expert on volcanos and climate at
Rutgers University in New Jersey, has looked at how much it might cost to carry
out one of the most commonly discussed geoengineering options, to mimic the
cooling effect of a volcanic eruption by filling the high atmosphere with
sulphur compounds, which reflect sunlight.
The eruption of Mount Pinatubo in the Philippines in
1991 threw so much shiny sulphurous dust into the atmosphere that temperatures
across a shaded Earth dropped a year later by about 0.5C. The 1815 explosion of
Mount Tambora in Indonesia triggered the notorious "year without a summer"
and widespread failure of harvests across northern regions including Europe,
the north-east US and Canada.
Robock has worked out the likely cost of technology
needed to deposit a million tonnes of sulphur in the stratosphere each year, an
amount equivalent to a Mount Pinatubo eruption every four to eight years, and
which scientists think could be enough to cancel out the global warming caused
by a continued rise in carbon emissions.
The cheapest option could be to use giant mid-air
refuelling aircraft, such as the US air force's KC-10 Extender, filled with
sulphur dioxide or hydrogen sulphide gas. It would be a round-the-clock
operation, with nine aircraft each required to fly three sorties a day. In a
new paper in the journal Geophysical Research Letters, Robock and his
colleagues say it could be done for "several billion" dollars a year.
The results have forced Robock to revise a high-profile list of 20 objections
to geoengineering he published last year. "It turns out that being way too
expensive is not the case."
Robock's new analysis still includes 17 reasons why
geoengineering is a bad idea. Throwing sulphur into the atmosphere could slow
down the world's water cycle and do more damage to rainfall patterns than the
global warming it aims to prevent. And because techniques that focus on
stopping sunlight do nothing to stop carbon dioxide pollution from cars,
factories and power stations, they cannot address the looming disaster of ocean
acidification. The surface of the world's ocean is slowly turning to acid as
our extra carbon pollution dissolves in seawater. Coral reefs already appear
doomed and many shellfish could follow. Altering the atmosphere could also
weaken solar power and reverse years of work to close the hole in the ozone layer.
With such a catalogue of potential disasters waiting
to unfold, there must be a law against geoengineering? The international
rulebook is fuzzy on this issue. The only international framework that directly
covers many geoengineering techniques, the 1976 Environmental Modification
Convention, designed to stop nations at war from meddling with each other's
weather, has never been tested. The 1982 UN Law of the Sea Convention and the
1967 Outer Space Treaty could be used to regulate activities and experiments in
those shared spaces, but releases to the atmosphere are legally more
problematic because nations have sovereignty over their own airspace.
Rather than laws and treaties, many experts argue that
the best way to prevent countries or companies from going it alone is to plunge
in and start serious research. "The way to tame the worst forms of
unilateral geoengineering is to promote a lot more research, especially [into]
the side effects," Victor says. "One of the biggest dangers is that
some governments will try to create a taboo against geoengineering. A taboo
would stop a lot of research but it wouldn't stop determined rogues. That
scenario would probably be the worst, because rogues would not abandon their
efforts and the rest of us would not have done enough research to know what to
expect."
Mike MacCracken, chief scientist at the Climate
Institute in Washington, is organising the California meeting next spring,
which aims to figure out some guidelines. He says large-scale unilateral
geoengineering is "not very plausible" and his main concern is
fairness to future generations. Once started by anybody, a geoengineering
attempt would probably need to be continued by everybody else because it would
offer a mask on global warming that could be dangerous to remove.
"It might be that this is how unilateral concerns
should be reframed; this generation more or less deciding it will take only
slow action on any type of emissions, essentially forcing the next generation
to be more likely to have to invoke geoengineering to save much that anyone
considers beneficial and unique about the Earth."
Read between the lines of most scientific reports on
geoengineering and there is a tacit assumption that the idea sounds so extreme
that merely discussing it will refocus efforts on emission cuts. But what if
the reverse is true? What if a heavily funded research programme, and articles
such as this, promote the idea to people who have little interest in moving to
a low-carbon world?
"Knowledge is hard to hide," says Robock.
"It would be great if people didn't know how to build nuclear bombs, but
they do. We need to research and debate the consequences and then use politics
and influence to let people know what would happen."
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