Hacking the atmosphere ‘could save the world’
Could geoengineering stop or even reverse climate change? Today, as the UN discusses carbon emissions at a global conference, politicians in the USA will debate a far more radical solution.
“Thanks to a system of satellites, natural disasters have become a thing of the past,” says the president of the United States. “We can control our weather.”
This is the premise of the new Hollywood blockbuster, Geostorm. As two scientists politely put it recently, the film is “deeply unrealistic”.
Yet it has roots in a genuine scientific debate: how seriously should we take geoengineering? The UK’s Royal Society describes this as “deliberate, large-scale manipulation of the planetary environment”. Today members of the US Congress will discuss it.
The theory is that, instead of reducing carbon dioxide (CO2) emissions, the world uses ambitious technology to “hack” Earth’s atmosphere and reduce the effects of global warming.
These potential technologies are generally split into two main camps. The first involves sucking up excess CO2 which causes the world to overheat. This could mean anything from planting more trees to capturing CO2 and storing it underground.
The second is “solar radiation management”, which involves deflecting the sun’s rays. Ideas include “cloud brightening” — literally making clouds more reflective — and “stratospheric aerosol injection”. The latter involves spraying tiny reflective particles into the upper atmosphere.
Earlier this year Donald Trump, the US president, announced that he planned to pull America from the Paris agreement, in which countries pledged to reduce their CO2 emissions.
Some think Trump and his team are leaning towards geoengineering as an alternative solution. Rex Tillerson, the secretary of state, has even referred to climate change as an “engineering problem”.
For now the technology is still theoretical, but the debate about it matters. Last week a report found that CO2 in the atmosphere was at its highest in 800,000 years. This week, as a UN climate conference discusses how to reduce emissions, it was announced that 2017 will be one of the warmest years on record.
Is geoengineering the solution?
Geostorm in a teacup
“Bring it on,” say enthusiasts. Climate change must be dealt with quickly, as the slew of violent hurricanes this year has shown. It looks increasingly unlikely that the world will keep temperature rises to 1.5°C, the target set by the Paris agreement. Anything above that could be catastrophic. We must do all we can to prevent it, no matter how radical.
“It is a bad idea,” say others, including many scientists conducting the research. We have no idea what the consequences could be; some think aerosol injection might accidentally end up causing widespread droughts, leading to vast food shortages. The entire debate is a distraction from the real solution: convincing people to stop burning fossil fuels.
- Which of the geoengineering technologies suggested in this article is the most promising?
- Should countries abandon the Paris agreement in favour of geoengineering?
- Split into groups. Design a geoengineering technology based on one of the ideas in this article, or one of your own. Label your design to show how it will work, and then pitch your idea to the rest of the class. At the end, vote for your favourite.
- Imagine that you are an adviser to Donald Trump, the US president. Research some of the reasons why 2017 is another record-breaking warm year. Then produce a short report which explains what you have found, and what the USA could do about it.
Some People Say...
“We are no more qualified to be the stewards or developers of the Earth than are goats to be gardeners.”James E. Lovelock
What do you think?
Q & A
- What do we know?
- Geoengineering is not a new idea — in its modern form, it has been around since 1945. During the cold war the USA and Soviet Union both considered altering the world’s atmosphere by exploding atomic bombs in space, although this was for military purposes. The dream of controlling nature stretches all the way back to the myths and scientists of ancient Greece.
- What do we not know?
- Whether it would work. As science historian James Fleming points out, in the Greek myth about controlling nature, Zeus ends up killing the hubristic Phaethon for losing control and almost burning up Earth. He argues that this should be a warning to modern scientists: we never know what the consequences of our actions will be. If geoengineering went wrong, the entire planet would be affected.
- Carbon dioxide
- A gas produced when burning fossil fuels (coal, oil and natural gas). It causes the greenhouse effect which warms the Earth’s temperature.
- More trees
- Plants convert carbon dioxide into oxygen through photosynthesis.
- Earlier this year, a Swiss company opened the first power plant which captures the CO2 it produces, compresses it, and then uses it as a fertiliser to grow crops. It claims to produce “negative emissions”. Others have suggested storing CO2 underground.
- In March Harvard professor David Keith announced plans for a small experiment involving a balloon that sprays small amounts of reflective particles into the stratosphere.
- Paris agreement
- The climate agreement was made in 2015, aiming to keep global temperature rises under 1.5°C. It will not come into effect until 2020. This week Syria said it would join, meaning the USA could end up being the only country not involved.
- According to the World Meteorological Organization (WMO), last year’s increase in CO2 was 50% higher than the previous decade’s average.
- According to the WMO.