A recent report highlights the importance of understanding and reducing disaster and climate risks in B.C.
The B.C. Disaster and Climate Risk and Resilience Assessment (DCRRA), the first in-depth update on provincial risk since 1997, flags rising temperatures and sea levels, and the potential implications of earthquakes, including a megathrust with a magnitude of 9.0 should it strike off Vancouver Island.
Notably, the report warns that the annual average surface temperature in B.C. is rising much faster than global trends. Since 1948, temperatures in B.C. have increased by 1.7 C, with the greatest warming occurring in winter (+3.2 C). By approximately the 2050s, the B.C. climate is projected to increase by 2.5 C, and by the 2080s, by 4 C, making extreme heat events “likely to almost certain.”
The report, authored by 21 experts, links rising heat and rising sea levels. For instance, at 4 C global warming, B.C. could experience a 12 per cent increase in overall precipitation and a 19 per cent rise in extreme rain events, leading to more intense storms and a higher risk of flooding.
Sea level changes have varied across the southern coast region, with Victoria seeing an average rise over the last century, while average sea levels fell in Tofino due to uplift caused by the subduction of the Juan de Fuca Plate beneath the North American Plate.
Victoria’s waterfront and low-lying areas could face noticeably higher water levels by the end of the century, making flood planning, coastal infrastructure upgrades, and emergency preparedness more important.
By 2050, Victoria’s relative sea level is projected to rise about 20 cm. By 2100, it could rise about 57 cm under the high-emissions scenario.
The report’s hazard exposure analysis found that about 5 per cent of the provincial population is currently exposed to coastal flood, the vast majority is in the Metro Vancouver Regional District.
The report also highlighted earthquake vulnerabilities. It found that 92 per cent of the population in B.C. is exposed to seismic hazards, including ground shaking, liquefaction and seismically triggered landslides. Ninety per cent of businesses in B.C. and 76 per cent of critical facilities are exposed to seismic hazards.
Overall, the DCRAA focuses on six hazards – riverine flood, coastal flood, extreme heat, wildfire, drought and water scarcity, and earthquake – and serves as a resource for provincial ministries, First Nations, local governments, infrastructure owners, health authorities and others.