As a kid I was always fascinated by Michael Moorcock’s The Ice Schooner – his version of Moby Dick set on a future Earth frozen from pole to pole. I had the Rodney Matthews poster of the ship on the bedroom wall.
Since Moorcock wrote that book we’ve discovered there was indeed a snowball Earth some 600 million years ago. The whole planet was one giant glob of ice, punctuated with occasional lakes. (Hope I’ve got snowshoes stashed away in my Tardis…)
The more recent ice age – the Pleistocene event – started around 1 million years ago and involved a succession of flip-flops between warm periods and glaciations, themselves punctuated with periods of even more extreme cold. It didn’t freeze the planet pole to pole, though. Our Eurocentric scholarship always leaves the impression of a world swathed in ice. Actually, it was northern Eurasia, Canada-North America, and chunks in the southern hemisphere – including Antarctica. Tropical areas were ice-free. The planet was drier than it is today.
Nobody knows what triggered the ice ages of the Pliestocene. But one thing is clear; the switches happened quickly. Terrestrial climate, it seems, is a meta-stable product of a whole lot of factors. Change one, and the point-of-stability shifts – quickly – to a new equilibrium.
What this meant was that ice advanced and retreated cyclically, sometimes switching from one phase to another in a generation – bringing with it dramatic shifts in the environment, as taiga and tundra moved with the glaciers. Animals had a hard time. Humans had a hard time too – there is evidence that these cycles did in the Neandertals, whittling down their habitats and numbers. The last survived until 24,000 years ago, in Gibraltar. Paleo-anthropologist Clive Findlayson argues it was just luck that the same didn’t happen to Eurasian populations of H. Sapiens, living further east.
Those same cycles repeatedly locked up vast quantities of water in ice sheets, making the sea levels rise and fall like yo-yos. This was still happening even after the end of the last big glaciation around 12,000 years ago. Changes in climate made it possible for farming to develop around the Black Sea, then a fresh water lake. But a huge area of ice remained in northern Canada – trapping meltwater as Lake Agassiz/Ojibway. Around 8200 years before the present, the ice dam was undermined and the melt-water escaped. Boom! World sea levels shot up by around a metre in just a generation – the Bosphorus was breached, and the Black Sea filled, driving early farmers off.
All this is fodder for writers. Stephen Baxter has set novels in a world where a sea wall kept Britain attached to Europe, via ‘Doggerland’. But jump back a little and we’ve got a whole different world – a Eurasia of taiga, tundra and emerging civilisation. Jericho was flourishing. So was Catal Huyuk. There were villages dotted around the Middle East and into eastern Europe.
Around them the land was undergoing dramatic climate change and sea-level shift. How would the earliest farmers – still using neolithic tools to scythe their wheat – have handled it? Would it have provoked new religions? Brought out the best in people? Brought out the worst? What do those responses say for our own future?
Archaeologists can only partially answer these questions. There’s room for novelists to play – and, maybe, to spring a whole alternate history.I think I’ve just inspired myself to have a go. How about you?
Copyright © Matthew Wright 2012