08 Jan 2020 19:38 IST

How geo-engineering could change the environment

This controversial approach may offer a reprieve as we deal with the larger fallout of climate change

For long, it was dismissed as an idea that was too outlandish. But now, it is slowly becoming acceptable. Today we are in an era of climate emergency. We have to hit global warming with everything we have — and deal with some of the consequences later.

All actions that governments have been planning (and planning, and planning) need to work in the medium to long term. Global warming doesn’t allow us the luxury of time. It is not a problem that will suddenly surface in 2100, the target year for limiting the planet from heating up beyond two degrees Celsius, from the average temperatures of the mid-19th century. It is a here-and-now problem.

If you have any doubts, look at what’s happening in Australia. The raging, uncontrollable forest fire not only took its toll on human lives but wiped out an estimated 480 million animals and birds. It is a big folly to ignore the loss of the faunal.

The quick-fix

One quick-fix approach to cool Nature’s temper is the bunch of measures that goes by the name ‘geo-engineering’. The best known and most often quoted of them is ‘solar radiation management’ or SRM — spraying of aerosol particles in the stratosphere which will reflect sunlight back into space. It is sunlight that gets converted into heat; it is the heat that is prevented from being radiated out into space by the layer of greenhouse gases — so less sunlight means less heat trapped.

While SRM is the most famous (or notorious, depending upon which side of the divide you belong), there are a few other tricks — such as ‘marine cloud brightening’, for increased albedo effect (reflecting back sunlight).

For years, geo-engineering was sneered at as being just some grand claptrap. A 2018 article in the prestigious Nature magazine called it “outlandish, unsettling and redolent of science fiction”. It based its stand on the idea that it is too early to know if geo-engineering actually works, or what its consequences would be.

Whether or not because of subsequent research, it is now accepted that it works. The second problem — what might be the fallout — remains. However, scientists in major universities — Harvard, Oxford and Cambridge — are now researching into this and also offering courses.

But now, the state of emergency that climate change has put mankind into forecloses any argument that geo-engineering might be harmful. The viewpoint that most people are taking is, if it works, let’s do it — we will deal with the consequences later.

The big question

There is a lot of theorising about the consequences, and they do not appear to be insurmountably bad. For example, one very real, deleterious consequence is that if SRM cools down the earth quickly, it will disincentivise other climate action. This is not good, because SRM is not — was never meant to be — a permanent solution, as it does not remove the delinquent greenhouse gases from the atmosphere (for which there are other geo-engineering responses). The last thing the world needs is for the developed countries to take the easy route of SRM and say they have squared up their responsibilities.

There is also this big question — what happens after some years, when the aerosol particles disappear?

Another possible fallout is the effect of SRM on monsoons. A cooler atmosphere will suck up less water from the oceans but to what extent?

Then, there are issues related to who will be affected positively and who negatively, aside from all the governance issues.

However, even if all these negatives are real, they constitute an acceptable risk, especially when weighed against the risk of climate change. Fact-sheet literature from Harvard University notes that “solar geo-engineering has the potential to significantly benefit the society and the environment.” It says that in economic terms, the potential long-term benefits likely exceed $1 trillion; comparatively, it would cost about $2 billion to $10 billion year to do SRM. Clearly the cost-benefit equation is favourable.

Academics and climate

Among the notable votaries of SRM is Prof David King, who has started a Centre for Climate Repair in Cambridge University. Prof King’s quote is oft-repeated in the context of SRM. Highlighting the urgency of climate repair, at a conference, he said, “What we do over the next ten years will determine the future of humanity over the next 10,000 years.”

Prof King’s Centre intends to come up with radical solutions under geo-engineering. SRM is one, for sure, but there are others too. For example, they want to take ships to the polar regions, ships which will feature very high masts. Through nozzles on top of the masts, using pumps, they want to spray sea water very high up, to create a cloud of white salt particles that will reflect sunlight back into the atmosphere.

And they are working on solutions to make the oceans ‘greener’, perhaps by multiplying organisms, so that the oceans could absorb more carbon dioxide, without making the waters acidic. The approach to doing this is to push a lot of nutrients into the oceans so that the organisms multiply more rapidly.

Geo-engineering could buy the world some time to deal with climate change. By the looks of it, it is worth trying out.