Water, water everywhere

Jim Harris posted this article on his blog.  It’s nothing new.  Just reminding us that the glaciers are melting, faster even than we had expected.  It focuses on the implications of glacial melt, with little reference to any other aspects of climate change.

But new data show the melting of glaciers worldwide is accelerating faster than anyone previously thought. According to the Swiss-based World Glacier Monitoring Service, 30 key international glaciers lost on average 66 centimetres of thickness in 2005. Those glaciers are melting about 1.6 times faster this decade than they were in the 1990s, and about six times faster than in the 1980s.

***

The melting of glaciers also has huge implications for future hydro-electric generation in the north, for commercial navigation on the Mackenzie River, for rare life forms that rely on glaciers, for more southerly weather patterns and for low-lying coastal communities everywhere.

Greenland, for example, has 1.8 million square kilometres of ice that is on average 2.3 kilometres thick. If it were to melt completely, ocean levels would rise by up to seven metres.

That’s not going to happen any time soon. But scientists at the University of Colorado at Boulder recently found that glaciers and ice caps, more than Greenland or Antarctica, are mostly responsible for the ice in the world’s oceans. They estimate that glaciers and ice caps are contributing about 417 cubic kilometres of ice, as much water as there is in Lake Erie, each year.

Not only has this flow of ice been steady, it’s rising by about 12.5 cubic kilometres per year. If it continues to rise at that rate, many of the 104 million people who live within a metre of sea level may have to move by the end of the century.

The only observation I can add to this dismal assessment is that the confidence that Greenland won’t melt anytime soon is rapidly disappearing.  We were expecting an ice-free arctic by century’s end.  Thomas Homer Dixon recently stated that based on currently observed patterns of melt, he expected it to be ice-free by the middle of the next decade.  Similarly, some scientists are saying that not only is Greenland melting much faster than they expected, but the moulins visible in its glaciers are worrisome signs that it may be as unstable as the Larsen B ice shelf which suddenly and unexpectedly dropped into the sea overnight a few years ago.  Some are cautiously suggesting the possibility that Greenland may melt within a few decades.  And that would create that 7 metre rise in sea levels referred to, and flood the homes of hundreds of millions.*

I want everyone to pause for a moment and consider the tragedy of Hurricane Katrina, which displaced 100,000 and multiply it perhaps 3,000 times.  I very much hope such dismal projections prove to be wrong, that the more conservative estimates are correct.  But why on earth are we toying with such possibilities?  How can any legislator with a conscience read such possibilities and continue funding tar sands expansion?

*A one metre rise in sea levels would displace 56 million people.  Five metres would displace 240 million.  10 metres would displace 634 million.