Portal shows areas most vulnerable to extreme heat

A new online portal launched by the Capital Regional District shows areas where people may be most vulnerable to extreme heat and how they can prepare.

The portal’s heat-exposure maps show urban heat islands — high concentrations of people, roads and buildings that make an area hotter — along with tree canopies and elevation levels where ocean breezes can have a cooling effect.

The mapping was developed with Island Health, municipal partners and the province.

The portal shows areas where people may be most vulnerable to hotter temperatures due to their age and health issues, taking into account the types of buildings they live in.

Esquimalt Mayor Barb Desjardins, who chairs the Environmental Services Committee, said the portal will help planners and emergency managers identify areas of risk and better plan for extreme heat. The CRD said the region is experiencing hotter summer temperatures, with more extreme heat days and heatwaves.

In the summer of 2021, a heat dome claimed more than 700 lives in the province, with 24 of those in the capital region.

The portal’s Demographic Vulnerability Index shows areas where residents had a range of health concerns (such as heart disease or substance-use disorder) and certain sociodemographic characteristics (such as being older, having low income or living alone).

The index is considered a “robust assessment” of vulnerability based on data and health concerns that occurred during the 2021 extreme heat event, said the CRD.

The Building Vulnerability Index identifies building factors such as age and height that can indicate higher indoor temperatures.

The CRD said heat-related deaths that can happen during extreme-heat events are often a result of high indoor air temperatures caused by heat exposure on rooftops, walls and windows, as well as indoor appliances and lighting.

The portal was developed with climate projections showing the region will see continued higher temperatures during the day and overnight during the summer months, and less rainfall.

Land surface temperature mapping using thermal infrared imaging is useful in understanding changes in development, land use and building energy use, said the CRD.

The CRD and its partners received funding for the portal through a $150,000 grant from the Union of British Columbia Municipalities Community Emergency Preparedness Fund.

To see the heat information portal, go to heat.prepareyourself.ca.