Pace of warming quicker than previously thought, UVic researchers say
Feb 01 2012
Waterfront property owners in B.C. probably need to bolster defences against rising ocean levels over the next century and forestry companies should be looking nervously at the absence of bug-killing cold winters.
An analysis of 62 years of Environment Canada weather data by the University of Victoria's Pacific Climate Impacts Consortium has found that B.C.'s temperature has been warming by about 0.25 degrees Celsius per decade.
While that may sound minimal, it is substantially more than the 0.13 degrees Celsius per decade reported by the Intergovernmental Panel for Climate Change for the years 1956 to 2005.
"That means in the past decade B.C.'s climate was more than one degree warmer than it was in the 1950s and that's quite a lot. It's more than we see in global measurements," said Francis Zwiers, PCIC director.
Despite the noise and annual temperature fluctuations caused by El Nino and La Nina (warming and cooling in the eastern Pacific Ocean), and the fact that 2011 temperatures in B.C. were about average, eight of the last 15 years in B.C have been among the 15 warmest years since 1950, Zwiers said.
"That would be very unusual by random chance," said Zwiers, an internationally recognized expert on climate variability and change.
"It's clear we are being affected by global warming . . . It becomes very clear that humans are part of the story. Increasing greenhouse gas emissions are leading to a warmer climate."
The effect can already be seen in the mountain pine bark beetle infestation, Zwiers said.
The bugs flourished because there were not sufficient extreme cold stretches to kill them off.
Extreme minimum temperatures are warming faster than extreme maximum temperatures all over the world, Zwiers said.
Sea levels are rising because of heat dropped into the ocean by greenhouse gases and also because of melting glaciers and ice sheets. In the coming decades, low-lying areas such as Delta and Vancouver International Airport will be at risk, Zwiers said.
Most parts of Vancouver Island are less vulnerable, he said.
However, all British Columbians should think about what infrastructure should be developed on the shoreline if it is going to survive the next century, Zwiers said.
"We are going to have to retreat from some areas."
Even if greenhouse gas emissions are brought under control, ocean levels are likely to continue to rise, Zwiers said.
"We are going to have to bite the adaptation bullet."