The dangers of white sky thinking

Apparently all the covid virus in the world could fit into a soft drinks can with space to spare. The calculation is set out in a piece by the mathematician Christian Yates in an article for The Conversation. The question was originally posed by my favourite Radio 4 programme, More or Less, and it got me thinking about a similar question the programme asked a few years ago.

In 2011 it set out to test the notion that the whole of the world’s population could fit on the Isle of Wight. The experiment in those distant pre-covid days involved squeezing Radio 4 staff into a 4m² studio and then scaling up. The answer was that it was just possible but would be a bit of a squeeze.

The American urbanist Edward Glaeser did something similar in his book Triumph of the City, calculating that all of humanity could live in Texas, except in this case we would all have our own personal townhouse. Texas is huge, of course, so in my lectures I translate this for a UK audience by suggesting the world’s population could live in a city the density of Paris and the size of Yorkshire.

The point being that despite there being 7.6 billion of us on the planet, there is also a lot of space. The problem of cities and urbanism is one that we should be able to deal with. The second point, driven home by the covid-in-a-Coke-can calculation, is that there don’t need to be that many of us to have a devastating effect. At the risk of being over-dramatic, as far as the planet is concerned, we are the virus.

I have recently finish reading two books that address this subject. The Ministry of the Future by Kim Stanley Robinson is a work of science fiction set in the near future. It opens with a harrowing sequence in which a “wet bulb” event (a heat wave with high humidity) kills tens of millions of people in India. The Indian government, in the face of international opposition, seeds the atmosphere with sulphur dioxide to dim the sun. This idea lies behind the title of the second book, Under a White Sky by Elizabeth Kolbert, because the sulphur dioxide would turn our skies white (a bit like living in Manchester, was my wife’s reaction).

The eponymous Ministry of the Future is a fictional UN body set up to solve the climate crisis. Meanwhile eco terrorists (possibly supported by the ministry’s black ops division) take hostage the Global Economic Forum at Davos and use drone swarms to bring an end to global air traffic and shipping. Elsewhere geo-engineers pump meltwater from under glaciers spraying it on the surface of the ice sheet to create new snow. Eventually the world’s financial institutions accept the idea of quantitative easing based on a carbon coin and, without spoiling the ending, everyone, including the planet, lives happily ever after.

Under a White Sky is science fact rather than fiction and paints a rather more pessimistic picture. It documents the history of our attempts to engineer nature, from the re-engineering of river systems to the introduction of invasive species. Kolbert tells us we nearly always get it wrong and that the unforeseen consequences are often far worse than the problems we were trying to solve.

Seeding the atmosphere with sulphur dioxide is a case in point (apparently diamond dust would be better). She likens it to a heroin addict on methadone. We might lower global temperatures but we risk creating famine and drought and, if we continue emitting CO₂ and then at some point stop seeding the atmosphere, the global temperature shock would be devastating.

The scientists she speaks to are studying this not because they think it’s a good idea, but because they fear that some time soon a country like India will decide to do it and it would be good to try and understand the consequences.

In the end Kolbert concludes that of course we need to transition to a zero-carbon world economy at a rate beyond the Paris agreement. But there is a good chance that even then it will already be too late for many planetary systems.

We are going to need all the geo-engineering we can get to stop the planet collapsing in the interim period before our action on carbon emissions has an effect on global temperatures.