Dwight Eisenhower famously said, “Whenever I run into a
problem that I cannot solve, I always make it bigger. I can never solve it by trying to make it
smaller, but if I make it big enough I can begin to see the outlines of a
solution.” And so it follows that geo-engineering,
the idea that the effects of climate change can be reversed by large-scale
engineering projects, is gaining traction in world where solutions have become
increasingly modular and entangled. Due
to the complications brought on by rising temperatures and competing interests,
the appeal of a “silver bullet” has never been higher. It is for these reasons that I wanted to
learn more about the potential of geo-engineering solutions and why I picked up
Oliver Morton’s book, The Planet Remade: How Geo-Engineering Could Change the
World.
It doesn’t take a lot to note the difficulties faced by conventional
climate change solutions that involve more cleanly producing, or more
efficiently using, energy. The book
notes that even if the world had the capacity to deliver one of the largest
nuclear power plants ever built once a week, it would take 20 years to replace
the current stock of coal-fired plants (at present, the world builds about
three or four nuclear power plants a year, and retires old ones almost as
quickly). To replace those coal plants
with solar panels at the rate such panels were installed in 2013 would take
about a century and a half.
More broadly, energy transitions just take time – for the
steam engine to completely replace the energy of the horse-drawn cart and the waterwheel
took about a century. The accelerating
effects of the IT revolution will greatly reduce transition time moving
forward, but the point remains that renewable energy and energy efficiency
gains are a hard slog.
Furthermore, environmental policies are often distorted as
they reach prominence, mutating to appease voters and lobbyists to the
detriment of their original vision.
People see wind turbines being built in prodigious numbers and see solar
cells on roofs and think they are looking at the solution. Plenty argue that, impressive as these sights
are, they are not achieving enough in terms of providing sustainable power or
mitigating the effects of climate change.
Consequently, the allure of geo-engineering undoubtedly lies
in an almost instantaneous relief from the mental fatigue of continually
combatting the problem. Climate geo-engineering
can be pursued in many different ways, but the aim is always to decouple the
climate from humanity’s cumulative emissions of carbon dioxide and to avoid the
worst effects by preventing temperature rises.
It is to unshackle, if only to a very limited extent, the future from
the past and thereby continue with life as we know it.
Humans know two ways of making a difference to the workings
of the “earthsystem” (as Morton rather flamboyantly likes to refer to
interconnectedness of the earth’s climate and energy). One requires large, species-wide effort, such
as millennia spent devotedly farming, or a century’s concentrated effort devoted
to the burning of fossil fuels. The
other requires finding a small thing that makes a big difference – something
that offers leverage. Finding that powerful lever is the key to geo-engineering.
With this picture in mind, I want to set out the broad
categories of geo-engineering ideas that I intend to cover:
- Cloud (or Veil) creation;
- Cloud seeding;
- Increasing the oceans’ alkalinity; and
- Increasing the reflectivity of Earth’s surface.
Cloud/Veil creation
The most obvious way to find a lever is to imitate nature. In 1990, the volcano of Mount Pinatubo in the
Philippines let out one of the most violent eruptions in recent history. The monstrous cloud of ash and dust that was
immediately sent flying up into the stratosphere included more than 20 million
tonnes of sulphur dioxide.
Dry as the stratosphere is, it still contains some water
vapour, and the sulphate ions within sulphur dioxide turn this vapour into tiny
droplets that create an aerosol mist. Because
sulphate drops are smaller than volcano ash, the mist can then stay in the
stratosphere for years. This is of interest
to geo-engineers because the droplets are so tiny that they create remarkably
high combined surface area, thus creating a veil-like effect against solar
radiation. In fact, studies have shown a
veil could be created that would offset two thirds of global warming.
However, the manner in which Pinatubo delivered 20 million
tonnes of sulphur dioxide to the stratosphere was surprisingly
inefficient. The gas rose because it was
hot and buoyant; keeping it hot and buoyant when was the business of the millions
of tonnes of hot rock thrown up into the air with it. A system designed to lift the gas alone could
do it with a lot less waste (and destruction).
The obvious way to do it would be to lift the gas in an
aircraft. Morton proposes a fleet of 14
Boeing 747-400 jumbo jets at a cost of a bit less than a $1 billion, and a year’s
operating costs at another billion. However, spraying out aerosols behind a
jumbo jet would be less than ideal. With
a ceiling of 14 km (45,000 ft), 747s can’t get above the tropopause in the
tropics, where the veil could be most effective. They would only be able to put aerosols into
the stratosphere in temperate and high latitudes, and then only into its lowest
reaches. That would limit the aerosol’s
ability to stay up for a long time and spread around the world.
In principle, a ton of gas can be lifted to the skies with
about 70 kilowatt-hours of energy, which is not a great deal – less, in fact,
than you get from burning ten litres of gasoline. If you spread the process out over a year,
you could lift 20 million tonnes into the stratosphere with a constant output
of about 160MW – the sort of power you can get from a power station running a
couple of modern gas turbines.
Consequently, other engineers who have looked at the problem
favour vast balloons holding aloft 30-km hosepipes, attached at pumping
stations on the surface. However, the balloons would have to be very large
indeed. Larger than the 100m behemoths
that NASA uses to lift specialised telescopes into the stratosphere.
Mechanics aside, experience has taught us that veils of
sulphur dioxide create unintended consequences.
The post-Pinatubo sulphate aerosol supplied a lot of new surface area
for ozone-depleting chemistry. In 1992,
the amount of ozone contained in the stratosphere as a whole dropped lower than
at any other time on record. A decade’s
worth of thinning occurred in one year and the hole over Antarctica let in more
ultraviolet than ever before. So a geo-engineering
programme that employs sulphate aerosols would, as Pinatubo did, thin the ozone
layer globally, with particular notable effects at the poles.
Other expected effects had unexpected consequences. The aerosols were warmed by the sun and by
infrared coming up from the surface; the infrared they emitted as a result
warmed the stratosphere around them.
This warming was greatest in the tropics. So in the lower stratosphere the difference
between the temperature at the equator and that at the poles – the driving
force for so many of the Earth’s weather systems – increased. The greater flow of heat away from the
equator strengthened the circumpolar jet streams, locking the weather into
self-reinforcing patterns of increasingly extreme weather.
Scientists have looked at other aerosols such as oxides of
aluminium and titanium or even very small diamonds, but none have been proven
to be commercially, or environmentally, feasible.
And, as we see with a lot of geo-engineering projects, the
list of potential problems goes on:
- a veil could severely affect the hydrological cycle changing where the rains come and how often;
- to create a uniformly thick veil around Earth would be very difficult to achieve and sustain. Consequently, each region would be effected differently, creating groups of veil ‘winners’ and ‘losers’;
- on an aesthetic level, creating a veil would quite literally change the way we see the skies by creating a near-constant and unnatural haze; and
- perhaps most worryingly, as the veil increases in effectiveness, there is an ever-increasing threat of rapid warming that could be unleashed by not renewing it.
Cloud seeding
So what about the opposite?
If we don’t want to create a veil, why don’t we make clouds disappear?
In 1946, General Electric discovered that dry ice (frozen
carbon dioxide) and silver iodide could make tiny water droplets freeze. Thus, the idea for cloud seeding was born
where, if you drop a few kilograms of either out a plane, you could make it
rain. Hurricanes could theoretically be
rerouted and dust bowls watered.
Unfortunately, enemy states could also be soaked. Military interest in cloud seeding has always
been strong and it is known that techniques were covertly deployed in attempts
to render the Viet Cong supply routes in Laos too muddy to operate during the
Vietnam War.
According to the World Meteorological Organisation, there
were already 42 countries in 2013 using cloud seeding for hail suppression,
precipitation enhancement or both.
As powerful as this ability feels, the problem with cloud
seeding is quite obvious: you’ll never create enough rain to keep the global
temperature from rising. At best, cloud
seeding can be a useful string to the bow of climate change adaptation. At worst, cloud seeding can be a nefarious
tool used by wealthy countries to push weather problems onto their poorer
neighbours.
Increasing the ocean’s alkalinity
Another popular idea is to make the surface waters of the
ocean more alkaline, thereby increasing the ocean’s ability to absorb carbon (after
which the ocean breaks down the carbon dioxide and sequesters it at the ocean
floor). The problem with this problem is
very similar to cloud seeding in that it doesn’t offer a huge amount of
leverage. In other words, it requires a
huge amount of input to create the requisite output.
Imagine using lime – calcium oxide – to add alkalinity. Morton notes that for every five molecules of
calcium oxide added to the seas, you could expect to draw down eight or nine
carbon atoms from the atmosphere.
Unfortunately, because calcium is a heavier atom, this means in order to
pull a billion tonnes of carbon out of the atmosphere we would need to pour two
billion tonnes of lime into the ocean.
Consequently, we’re talking about the excavation and relocation of a
natural resource on a scale similar to the coal industry. That’s without even considering what would
happen to the world’s marine and ocean life.
Who would pay for such a thing?
Politically, how would you sell the idea to the world that you are going
to dig up the ground and scar the earth in order to pollute the ocean and
fundamentally change its chemistry?
Other models have suggested using iron (a more expensive and
rare natural element). However, for such
a scheme to come close to sequestering a billion tonnes of carbon a year,
models suggest the entire Southern Ocean would have to be targeted. The cost and irreversible nature of such a
plan means that it would only be palatable to lime or iron-rich countries with
poor environmental records.
Increasing the reflectivity of Earth’s surface
A simpler and less divisive method to cool the planet would
be to bounce heat and light back into space.
Brilliantly elegant solutions are littered throughout the book:
- you could paint all the roofs in the world white, scatter the desert with metalised particles or even launch reflecting panels in the Earth’s orbit;
- you could genetically engineer crops to give them more reflective leaves (a plan currently being researched by Bristol University); or
- you could make clouds brighter in order to make them more reflective (Scientists are researching ways in which to brighten clouds by using the “Twomey Effect”. The Twomey Effect states that the smaller the cloud condensation nuclei (the specks on which water droplets form to create clouds), the brighter the cloud will be because there would be a greater number of smaller droplets and thus more surface area for a given amount of water which means more scattering of light by reflection. Smaller droplets also make clouds last longer. Clouds over the sea tend to have much lower numbers of nuclei than those over the land. Consequently, you might rectify this with some sort of system for making very little droplets of water near the sea surface; the water would evaporate, leaving behind little salt crystals which, by convection, would be sucked up to become condensation nuclei for brighter clouds).
However, these plans to be stored under “Science Fiction” for
now. The science is unproven and the
collective will does not yet exist. Try
telling someone in the depths of winter in Northern Alaska that painting there
house white will help keep the planet cooler or, try telling a poor South
American farmer to plant a different crop that could scare away his customers. Plans for such homogeneous action fails to account
for the variety of lifestyles and considerations that the human populace
possesses. Enforcing such a plan would
be painfully dictatorial, nevermind unrealistic.
A world already geoengineered
For all of the negative reaction and cries that it cannot be
done, geo-engineering the planet to our advantage is not a new or a novel
concept. Dams are changing the flow of
rivers, engineering works are altering the processes of erosion, agriculture is
redefining the global cycling of nutrients and patterns and pace of extinction
– which is to say, evolution.
Humans constantly outstrip nature with our dominance of the
nitrogen and carbon cycles and the amount of soil we move around with ploughs
and bulldozers, greatly accelerating the transfer of sediment to the sea and
creating completely new ecosystems.
The most striking deliberate human intervention in the
earthsystem lacks almost any hint of the sublime. No awe-inspiring volcanoes; no nifty
stratospheric jets; no angsty symbolist sunsets: just bags of fertiliser. When fertiliser fixes nitrogen (taking an
inert gas from the air and turning it into something biologically useful – see
the Haber-Bosch process designed in 1919 that first fixed nitrogen and directly
led to the global use of fertiliser), the cycle of nitrogen was irreparably
altered. As we continue to pull nitrogen out of the atmosphere and put it into
the ground, we are now oversupplying nitrogen to the soil, which is ironically
killing the fertility of the soil it once sought to invigorate.
Consequently, we already live on a vastly disrupted
planet. Why shouldn’t we disrupt it a
little more?
Conclusion
The inescapable truth about geo-engineering is that it is
not an antidote to climate change; it is an additional form of climate change.
An additional form of climate change that has some effects that work counter to
those brought on by greenhouse warming. Even if one were to know for sure that
intervening in the climate would reduce the risks the world faces, it would not
follow that such intervention was necessarily a good idea.
If I assert that a geo-engineering scheme will not succeed
due to some sort of technological inertia, some scientific hubris, or by the
intervention of some commercial interest or political power, then I must to
accept that the same is true of more or less any big international attempt to
deal with the climate. However, as
compared to more traditional climate change mitigation or adaptation
techniques, I find the following problems to be insurmountable:
- Implementing geo-engineering solutions creates a moral hazard, in that, it disguises the underlying problem and allows us to continue the original behaviour. I think having such an insurance policy only encourages more risky behaviour.
- There are no laboratories big enough to know for sure how geo-engineering projects will actually play out once unleashed globally.
- Whose hand is on the thermostat? Almost every level of geo-engineering would be suboptimal for at least some regions of the planet. All could be winners, but all would be in a different position if the system were deployed differently. Which countries or organisations are able to make such decisions for the world? And how would they be held accountable?
- Making geo-engineering a bigger part of climate change discussions and taking the prospect seriously, is difficult, dangerous and unpalatable. It normalises what should remain an outrage. A world in which such things are discussed is a world less natural.
- Once implemented, the operator holds a disproportionate amount of power as to stop the programme would be to invite a sudden and dangerous degree of warming.
- But perhaps most importantly, geo-engineering is a top-down solution in world where we all want to be empowered.
I would not discount geo-engineering completely. Some of the solutions suggested above can be sensibly
integrated into a larger adaptation arsenal with minimal risk. However, the lever that we need to find will
not manifest in a physical place or a specified action. It will be an institution, a shared goal, a
new understanding of nature, and an obligation of solidarity to address the
underlying cause, rather than to mask the smell.
Morton’s book was a challenging and, at times, overly
verbose read. His flowery use of prose
and overly simplistic optimism surrounding the subject only sought to convince
me of the opposite. Cutting against
President Eisenhower’s sentiment, when it comes to climate change solutions, I
have yet to see a viable short cut.
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