Stephen Rees's blog

Thoughts about the relationships between transport and the urban area it serves

Posts Tagged ‘floods

Rising sea levels, earthquakes to hit B.C., says study

with 3 comments

Richard Watts,  Vancouver Sun

Not a comfortable story for residents of the Fraser Delta to read. The conservative extimate of sea level rise from the IPCC is 90cm “by the century’s end” . But everything else I have been reading recently suggest things are going to start happening much faster than the IPCC predicted because they did not account for the “feedback loops” in the processes of global warning and climate change. For instance, as the polar ice caps have been melting, so less sunlight is reflected back into space and the dark surface of the ocean absorbs more heat than the bright surface of the ice. So that process can now be measured and shows the IPCC erred when it made its “conservative” estimate.

One major force is the melting of ice caps in the North and South poles and the world’s glaciers. This is coupled with an expansion in the volume of the oceans’ waters due to an increase in their temperatures brought on by global warming.

And that process can now be seen to be inundating low lying nations around the Pacific. Years – deacades –  before the IPCC thought they would be.

Meanwhile, in the Lower Mainland, the loading of sediment from the Fraser River is actually pushing the land surface downward, a process called subsidence.

Not only that, but the lack of dredging in the secondary channels of the Fraser (the Port only dredges the main shipping channel in the South Arm) means they are full of sediment. So there is less storage capacity for the spring freshet – the ice melt from the interior glaciers.

As also predicted, weather events have been getting more extreme, as global warming means there is more energy driving them. Climate change is not just wamer springs and longer dry spells – it is also more and worse storms.

So what we are looking at is a sesimically unstable area, that is sinking while sea levels rise – and the wetaher gets worse.  You might think that would be stimulating a lot of activity on the dykes – and a fresh examination of dredging policies, given the devasation that will occur when (not if) the dykes are overtopped. But so far all we have heard are platitudes and reassurances – not action. And my concern is that the message that this process has been speeding up is not being heeded by municipal, regional or provincial authorities.

Indeed, there is no sense of urgency at all in this story. Except for this little gem

“Once the big earthquake hits, within minutes the land all falls back down a metre or so and then the big tsunami hits, and it’s not going to be fun,”

Written by Stephen Rees

December 17, 2008 at 11:27 am