In a subscriber-only article over at New Scientist, NASA climate scientist James Hansen describes what the planet might look like after a "runaway collapse" of the West Antarctic ice sheet.
The collapse, or melting, of the sheet, of course, would be caused by increased global temperatures – temperatures altered by the atmospherically unique quantity of carbon dioxide that's now floating around up there. That carbon dioxide has been released by human industrial processes.
"There is not a sufficiently widespread appreciation of the implications of putting back into the air a large fraction of the carbon stored in the ground over epochs of geologic time," Hansen writes.
In any case, the article points out that this future sea-level rise will actually increase over time, as the melting of the ice sheet itself accelerates.
As an example, let us say that ice sheet melting adds 1 centimetre to sea level for the decade 2005 to 2015, and that this doubles each decade until the West Antarctic ice sheet is largely depleted. This would yield a rise in sea level of more than 5 metres by 2095.
That would be more than enough to flood London, as discussed in the previous post – not to mention Shanghai, New York, Mumbai, and so on.
>From the article:
Without mega-engineering projects to protect them, a 5-metre rise would inundate large parts of many cities – including New York, London, Sydney, Vancouver, Mumbai and Tokyo – and leave surrounding areas vulnerable to storm surges. In Florida, Louisiana, the Netherlands, Bangladesh and elsewhere, whole regions and cities may vanish. China's economic powerhouse, Shanghai, has an average elevation of just 4 metres.
This is obviously meant as a warning.
However, the main problem I have with using maps and scenarios like this to get people worked up about climate change is that these warnings often seem to have the opposite effect.
In other words, these things are actually so evocative, and so imaginatively stimulating, that it's hard not to get at least a tiny thrill at the idea that you might get to see these things happen. Nothing against Miami, but all of south Florida under several meters of water? With Cape Canaveral lost under a subtropical lagoon and St. Petersburg an archipelago?
The problem, it seems, is that climate change scientists, in describing these unearthly terrestrial reorganizations, are science fictionalizing, so to speak, our everyday existence. The implicit, if inadvertant, message here seems to be: hey, south Floridians, and all you who are bored of the world today, sick of all the parking lots and the 7-11s, tired of watching Cops, tired of applying to colleges you don't really want to go to, tired of credit card debt and bad marriages, don't worry.
This will all be underwater soon.
It could be called liberation hydrology.
Climate change becomes an adventure – the becoming-science-fiction of everyday life.
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<http://bldgblog.blogspot.com/2007/07/liberation-hydrology-miami-2107-ad.html>
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