'Global sunscreen' plan could wreck tropics, study finds

Jan 08, 2014 by Richard Ingham
Silhouettess of palm trees are seen on the sand in a beach in Bacolet, Tobago on June 6, 2009

An idea by the father of the H-bomb to slow global warming by sowing the stratosphere with light-reflecting particles could wreck the weather system in the tropics, a study said Wednesday.

The scheme may benefit northern Europe and parts of Asia, but around the equator rainfall patterns would be disrupted, potentially drying up tropical forests in South America and intensifying droughts in Africa and Southeast Asia.

"The risks from this kind of geo-engineering are huge," said Andrew Charlton-Perez, a meteorologist at Britain's University of Reading.

In 1997, US nuclear physicist Edward Teller and other scientists suggested spreading sulphate particles into the upper atmosphere, reflecting some sunlight back into space to attenuate the Earth-warming greenhouse effect from fossil fuels.

This sunscreen—similar to the cooling effect from ash spewed by volcanic eruptions—would be cheaper than switching out of coal, gas and oil which cause the global warming problem, they said.

The idea is a favourite among geo-engineers, who nevertheless concede that manipulating the climate system on a planetary scale should be a last-ditch option.

In a paper published in the journal Environmental Research Letters, the British scientists said it would take a staggering volume of particles, called aerosols, to reverse warming.

"To reduce global temperatures enough to counter effects of would require a massive injection of aerosol," said Angus Ferraro at the University of Exeter, southwestern England.

Each year, it would require the equivalent of five times the volume of ash disgorged by Mount Pinatubo in 1991—the biggest volcanic eruption in the last quarter of a century.

The model was based on upper-end projections of having to reverse the warming impact of atmospheric CO2 levels of 1,022 parts per million—compared to about 400 ppm today.

Such a high level would drive the Earth's surface temperature up by about 4.0 degrees Celsius (7.2 degrees Fahrenheit).

Tropical rainfall is big victim

The investigation, however, found that releasing the particles would have at least one serious side effect.

They would start to warm the and weaken upward convection from the troposphere, the lower levels of the atmosphere where weather takes place.

The result would be to put the brakes on a mechanism of atmospheric turnover and cause a sharp drop in rainfall in the equatorial belt.

"A reduction in of 30 percent would, for example, quickly dry out Indonesia so much that even the wettest years after a man-made intervention would be equal to drought conditions now," said Charlton-Perez.

"The ecosystems of the tropics are among the most fragile on Earth. We would see changes happening so quickly that there would be little time for people to adapt."

In August 2012, a cost analysis, also published in Environmental Research Letters, found that the basic technology to distribute aerosols exists and could be implemented for less than $5 billion (3.65 billion euros) a year.

This compared to a cost, in 2030, of between $200 billion and $2,000 billion (146 and 1,460 billion euros), to reduce carbon dioxide (CO2) to safer levels, it said.

That estimate, though, did not factor in any environmental risks.

In a 2009 overview of geo-engineering, the Royal Society, Britain's academy of sciences, said the advantage of aerosols was that they could be deployed quickly and start reducing temperatures within a year.

But they would not stop a buildup of CO2 from , nor prevent acidification of the oceans, which absorb the gas. There could also be a knock-on effect on rainfall patterns and on Earth's protective ozone layer, the Royal Society said.

Explore further: UN: CO2 pollution levels at annual record high

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User comments : 16

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alfie_null
3.5 / 5 (4) Jan 08, 2014
The cost is low enough that a single nation could take on the task, ignoring the desires or needs of other nations.
davidivad
4.6 / 5 (8) Jan 08, 2014
i am not comfortable with the idea of trying to alter our atmosphere. we do not know enough about the climate to justify this kind of action. it is my personal opinion that we first wait to see what kind of impact we are having on a larger time scale.
mosahlah
3 / 5 (6) Jan 08, 2014
We're already altering the atmosphere. But, this is something we can do to mitigate the effects of greenhouse gases, and it wouldn't be permanent, it would be easily adjusted or reversed, and we have some good data for models. How much do we really know about the effects of increasing CO2?
Qluq
4 / 5 (5) Jan 08, 2014
I don't know much about atmospheric chemistry, but wouldn't it be possible to come up with aerosols that "decay" into some harmless substance in a very controllable way / timeframe? By harmless I mean both in terms of toxicity, reflectivity and any other properties that are deemed important. Would that create an opportunity to cautiously experiment?
StillWind
3.6 / 5 (5) Jan 08, 2014
What an incredibly stupid idea. This just goes to show that even very smart people can make asses of themselves.
Fortunately, this wouldn't ever be attempted unless there was a real reason to do so, and so far there is no evidence to suggest that we do so,.
Returners
2.3 / 5 (6) Jan 08, 2014
How are we enjoying the "AGW induced record low temperatures" across an entire continent?

It is fortunate for us that the temperature has warmed, else we'd be another degree or 3 colder in the U.S.

Would the world be better off if the Mississippi froze solid all the way down to St. Louis as it used to do?

Hell no. It'd wreck the U.S. economy, and wreck trade with several other nations who rely on imports and exports with the U.S. heartland. It's a good thing we have all that waste heat from power plants and factories going in the river, as well as whatever global warming might actually be happening, to prevent this terrible disaster from happening.
deatopmg
2 / 5 (4) Jan 08, 2014
Included in an overwhelming amount of collected evidence, the major tenet of GHG warming theory, i.e. warming of the upper troposphere in the tropics, has been measured and found to be unchanging w/ rising CO2 (280 to nearly 400 ppm) and during that continuous rise, the earths temp has risen a little, fallen a little, risen a little, and not changed, so what is all the hysteria and panic about? History shows warmer is better anyway.

Those promoting extreme and runaway warming are scamming the system for our money. Who gets rich & who pays for that? Presently $1billion/DAY is being spent globally to counter so called man made warming. Politicians lavishly fund those promoting the catastrophe sic because their propaganda results in even more tax money for them to spend on poorly thought out schemes for their electorate and that helps get them re-elected. Diddling w/ the atmosphere is unadvisable!

Look at the evidence. Man made warming theory continues to be a dismal failure.
cantdrive85
1.8 / 5 (5) Jan 08, 2014
What an incredibly stupid idea. This just goes to show that even very smart people can make asses of themselves.
Fortunately, this wouldn't ever be attempted unless there was a real reason to do so, and so far there is no evidence to suggest that we do so,.

Ha ha... You don't look up much, do you?
https://www.googl...bih=1074
marcush
4 / 5 (4) Jan 08, 2014
Can't believe how moronic most of the comments here are. Web pundits know better than publishing scientists. It would be funny if it wasn't so tragic.

Modernmystic
1.5 / 5 (2) Jan 08, 2014
Can't believe how moronic most of the comments here are. Web pundits know better than publishing scientists. It would be funny if it wasn't so tragic.



Almost as funny as patent clerks knowing more than publishing scientists....

http://en.wikiped...uthority
marcush
5 / 5 (2) Jan 08, 2014
I think the patent clerk you are thinking of ended up publishing many papers and worked at Princeton. Let me know when you your fellow pundits do like-wise....
Whydening Gyre
5 / 5 (2) Jan 10, 2014
How are we enjoying the "AGW induced record low temperatures" across an entire continent?

It is fortunate for us that the temperature has warmed, else we'd be another degree or 3 colder in the U.S.

Would the world be better off if the Mississippi froze solid all the way down to St. Louis as it used to do?

Hell no. It'd wreck the U.S. economy, and wreck trade with several other nations who rely on imports and exports with the U.S. heartland. It's a good thing we have all that waste heat from power plants and factories going in the river, as well as whatever global warming might actually be happening, to prevent this terrible disaster from happening.

I get it - sarcasm...
julianpenrod
1 / 5 (3) Jan 11, 2014
It has been decreed by determined "debunkers" across the internet that it is impossible for any substances to be released into the atmosphere by a program such as "chemtrails" that would so significantly affect weather.
So characteristic, though, the corporations ruin the world, then, rather than rein them in, their puppet, government, puts the burden on the "rank and file" to moderate the damage! Rather than force the "medical" rackets and the insurance carrier crooks to toe the line, providing "healthcare" people can afford, Adolf Obama orders that everyone buy insurance. Rather than require companies not to use "fossil fuels", they plan to destroy blue skies for the "rank and file" forever.
But, then, it was found that sky blue tends to increase imagination. The New World Order doesn't want people to be able to conceive that the New World Order exists.
julianpenrod
1 / 5 (3) Jan 11, 2014
As is so often the case with craven, quisling stop gap measures, as opposed to actual solutions, that they cause at least as much harm as they end.
Giant umbrellas launched into space to block radiation that would warm the atmosphere would steal pleasant skies from the "rank and file", which doesn't necessarily mean much evidently to the "scientists", who appear more machine than human; they would ruin crops; and they would provide a threat of falling to earth.
Likewise with the aerosol plan reducing good weather and blue skies, humanity's birthright. But, note, too, while they may mediate the effect of carbon dioxide on global temperature, it can have other effects, as well. Among other things, contaminating breathing air to harm many people!
julianpenrod
1 / 5 (3) Jan 11, 2014
And all of this ignores that, in fact, it is "chemtrails" that cause climate change. From the early 1950's, when they began, and started the number of tornadoes per year to climb from a previous constant and started forming new cloud species to 1997 when they appear to have saturated the entire atmosphere. Note, since 1997 is when the staccato of significant signs associated with climate change began. Fossil fuels were in use for a century or more before, and only a minor fraction of carbon dioxide was added since 1997, too little to explain the sudden explosion of climate change effects. But the air being saturated with weather control chemicals since 1997 does explain it.
But the emphasis is placed on "fossil fuels" by Liberal forces who are heavily invested in things like windmills and solar energy, which, themselves, deleteriously affect the environment!
RealityCheck
not rated yet Jan 12, 2014
How are we enjoying the "AGW induced record low temperatures" across an entire continent?

It is fortunate for us that the temperature has warmed, else we'd be another degree or 3 colder in the U.S.

Would the world be better off if the Mississippi froze solid all the way down to St. Louis as it used to do?

Hell no. It'd wreck the U.S. economy, and wreck trade with several other nations who rely on imports and exports with the U.S. heartland. It's a good thing we have all that waste heat from power plants and factories going in the river, as well as whatever global warming might actually be happening, to prevent this terrible disaster from happening.

Compromising invested global agriculture/transport etc infrastructure etc is nothing to joke about. Your next meal/paypacket might be compromised along with it. More extreme/frequent 'events' does no-one any good; except maybe some irresponsible 'jokers' who might benefit 'locally'...for a while! Joke may be on you and yours. :)