Tuesday, December 11, 2012

The Tories May Not Believe It But Canada's Third Largest City Knows Climate Change Is Real

There's been an interesting series of articles in The Vancouver Sun  about climate change threats to the Lower Mainland.   The low-lying Fraser River estuary is particularly vulnerable.  It's a witches' brew of sea level rise, storm surges and rivers in flood being backed up by the sea.

“If you have a warmer atmosphere, you’re probably going to get more rain, so in the mid-latitude you could get a sequence of big storms,” said Gordon McBean, professor at Western University and director for research at the centre for environment and sustainability.

“The first couple of them could deposit all of their rain over the Interior of B.C., making the flow down the Fraser even larger, then at the same time, the winds blow the ocean over Georgia Strait, then you’ve got this extra water in the Fraser River running past New Westminster and hitting Ladner, the airport and areas under the Oak Street Bridge.

“This water is coming down the river at the same time as the wind is pushing the water from the Georgia Strait towards it so you get this kind of double effect.”
Insurers have no doubt about the reality of global warming impacts.

“The level of insured losses is going up so rapidly from flooding that the insurance industry has gone from thinking of itself as a fire mitigation agency to a flood mitigation agency,” said Deborah Harford, executive director of the Adapt to Climate Change Team (ACT) at Simon Fraser University.

“Half of every dollar that the insurance industry spends in Canada right now is on basement inundation, either because of greywater backup or because of somebody’s sump pump failing. Heavy precipitation is causing those damages. Even without insuring overland flooding, they’re already taking a catastrophic level of loss.”

Water seems to be the main problem with climate change, Harford said.

“It’s either too much, too little or there or not there when you really need it,” she said.

That heavy precipitation is likely to get worse as the pattern of storms changes in B.C.

We’re getting different kinds of storms, we’re getting different intensities of storms, different forms of precipitation at different times and in different forms,” said Stephen Sheppard, professor in landscape architecture and forest resources management at the University of B.C., who works with Collaborative Advanced Landscape Planning (CALP) engaging communities on climate change. “We used to get a lot of snow in the mountains, now we get rain on snow, which is disastrous for the streams because they get huge amounts of run-off."

Sea level rise also raises the threat of saltwater inundation of the rich Fraser Valley agricultural zone which could undermine the urban Greater Vancouver region's food security.

[UBC professor] Stephen Sheppard said agriculture in the area could be profoundly affected by rising water tables, increased salinity, and the effect of climate change on crops, such as different growing seasons or temperatures.

“All of these things together will probably change the face of agriculture as we know it in the Lower Mainland in this century,” said Sheppard, professor in landscape architecture and forest resources management at UBC.

Given that much of the land in the Agricultural Land Reserve, used to grow food in the Metro region, is in regions like Delta, Richmond and Surrey, which are low-lying, increasing salinity could have significant effects on the region’s food supply.

“Communities like Delta provide about one-third of the local food for the whole of Metro Vancouver,” Sheppard said. “There’s a knock-on effect for everybody because if agriculture is affected, it may be that the adaptation is to switch to different kinds of crops or different kinds of farming or different locations for farming.

“Maybe we have to move some of the farms into urban areas that are not at risk of flooding, so I think you will see a lot of interest in alternative forms of food production as a response to these kinds of threats.”

Lower Mainland municipalities are planning to meet the combined impacts of river flooding, sea level rise, storm surges and saltwater inundation but there is a reluctance to incur massive spending on problems that might be decades off.

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