Keyboard worrier

Monday, August 09, 2021

Climate change and contingency planning

The term ‘climate change’ is not helpful. If I am waiting for an elevator, it does not help me to know that its altitude is changing; I want to know if it’s coming my way or receding.

In the 1970s some scientists warned of global cooling because of, for example, aerosol pollution; others were neutral, but many predicted global warming, even then. https://www.newscientist.com/article/dn11643-climate-myths-they-predicted-global-cooling-in-the-1970s/ The word ‘change’ suits the fence-sitter, like the wall-sitter Humpty Dumpty with his personal definition of ‘glory.’ https://en.wikipedia.org/wiki/Humpty_Dumpty#Lewis_Carroll's_Through_the_Looking-Glass

Maybe we are wrong in trying to see the big picture as a unitary one. The Earth has extreme temperature variations – over 80°C in Iran https://www.sciencemag.org/news/2021/05/move-over-death-valley-these-are-two-hottest-spots-earth and -93°C in Antarctica https://www.sciencefocus.com/planet-earth/what-are-the-10-coldest-places-on-earth/ The middle point between those two is too cold for me.

We are still in an ice age; the last time the Arctic was free of ice was around 2.6 million years ago, after which geological change there allowed fresh water (which freezes more easily than salt-laden) to rebuild the ice sheets. https://slate.com/technology/2014/12/the-last-time-the-arctic-was-ice-free-in-summer-modern-humans-didn-t-exist.html Contrariwise, the last time we had a ‘Snowball Earth’ was 600-odd million years ago, possibly because the emergence of early land plants ate into atmospheric carbon dioxide, aka plant food. https://en.wikipedia.org/wiki/Timeline_of_the_evolutionary_history_of_life#Proterozoic_Eon So climate change can relate to both regional and global causes.

Even scientific measurements are not cut and dried. The consensus is that sea levels are gradually rising, but that is not easy to prove. https://science.howstuffworks.com/environmental/earth/oceanography/question356.htm Similarly, the height of a land mass above the sea varies – for example as glaciers melt, the reduction in weight allows the underlying rock to bob up.  https://en.wikipedia.org/wiki/Post-glacial_rebound It is difficult to establish with certainty what is changing, why it is changing, whether we are largely responsible, how we might stop it and – more controversially – whether we should, if we can.

We look for simple – but emotionally loaded - answers: this tripped up Piers Morgan, who thought he’d trapped the German teenager Naomi Seibt into denying ‘global warming’ and then (gotcha!) accused her of self-contradiction, forgetting that he’d used the adjective ‘catastrophic’, which is the point she was doubting. https://metro.co.uk/2020/03/04/piers-morgan-apologises-teen-activist-greta-thunberg-12348909/

As an amateur, I can only throw in several items that leave me, too, on the multiple fences above:

1. We are often told of the melting of Greenland snow and assume it is something to do with excess heat retained in the air because of carbon dioxide from power stations, or possibly methane from cow farts. Yet the Greenland melting has been studied for years by a glaciologist called Jason Box, who thinks it has to do with a surface dusting of atmospheric pollution from e.g. far-distant forest fires; the ‘Dark Snow’ https://www.rollingstone.com/interactive/feature-greenland-melting/ absorbs more of the sunlight’s energy.

2. Still in the Arctic, the circulating sea current known as the Beaufort Gyre https://en.wikipedia.org/wiki/Beaufort_Gyre has long been been hoarding fresh water (as before, above) but a change in its direction – which is said to happen periodically – could release great volumes of easier-freezing water into the North Atlantic and cool the climate in Europe. https://www.armstrongeconomics.com/world-news/climate/the-threat-of-an-ice-age-is-real/

3. Another theory that intrigues me is from a fellow internet writer who argues that there is an ice cycle: as falling snow turns to ice and builds up on land masses, it acts as a thermal blanket, sealing in heat rising from deeper in the Earth and so the global climate cools; the rocks accumulate heat until they melt the ice, releasing the energy into the air and so cooling themselves again; and repeat.

Where excess heat doesn’t belong, is in the scientific and popular debate. I would suggest we avoid over-assertion in our observations and forecasts, and instead concentrate on increasing our communal resilience in the face of unpredictable changes. We need to prepare for floods, droughts, extreme hot or cold spells, shortages of food and drinking water… and surely part of that preparation is to look at what size of population we can safely sustain, especially if we hit global problems of production and transportation, as has already happened in a relatively very minor way during the current pandemic.

5 comments:

Mark Wadsworth said...

For sure the climate is changing, nobody knows why.

What I know for sure is that the 'greenhouse effect' is actually caused by good old-fashioned clouds (as surprising as that might sound), it is only if you ignore clouds and their effect that you have to make up silly alternative explanations like 'greenhouse gases trapping radiation'.

Ergo, changes in CO2 levels cannot have any effect on temperatures.

Paddington said...

@Mark - Have you read any of the relevant Scientific papers? If you had, you would know that they take account of insolation (Solar cycles included), and levels of could cover, including those due to volcanoes.

@Sackerson - From the models that I have seen, Britain might get much colder in the Winter, as the warmer oceans divert the Gulf Stream.

Paddington said...

Check out the prediction by Exxon from 1982: https://xkcd.com/2500/

Sackerson said...

@P: and Exxon then did... what?

Paddington said...

@Sackerson - Exxon then started a massive PR campaign to try to negate that report, as well as hiring professors to look at the data, all of whom eventually accepted the conclusions. Simultaneously, the company is spending billions to prepare for Climate Change.