Munich RE's NatCatSERVICE provides information on relevant and catastrophic losses. Insured and uninsured losses are tracked for various events including hydrological events (floods, flash floods, severe storms) and meteorological events (hurricanes, storm surges, floods). Charts showing trends in losses are available from 1980 to 2017 expressed in 2017 $USD including:
- Nominal Overall Losses - values as they originally occurred
- Inflation Adjusted Losses - accounting for changes in monetary equivalent
- Normalized Losses - accounting for growth of values and assets (considering nominal gross domestic product)
|Normalized Flood Losses - Relevant Hydrological Events in North America 1980-2017 per Munich RE NatCatSERVICE|
|Normalized Flood Losses - Catastrophic Hydrological Events in North America 1980-2017 per Munich RE NatCatSERVICE|
|Normalized Flood Losses - Relevant Meteorological Events in North America 1980-2017 per Munich RE NatCatSERVICE|
|Normalized Flood Losses - Catastrophic Meteorological Events in North America 1980-2017 per Munich RE NatCatSERVICE|
|Catastrophic Losses Adjusted for Growth in Net Written Premiums in Canada - per Robert Muir's Thinking Fast and Slow on Floods and Flow.|
How about Canadian trends? The following NatCatSERVICE chart was provided by Munich RE specifically for Canada. It shows some increasing trends in losses after accounting for inflation just as the chart above with Canadian catastrophic losses normalized by growth in net written premiums.
Looking at data from the Insurance Bureau of Canada including loss data and net written premiums, we see both of these values increasing in recent decades as shown below.
The following charts show catastrophic losses vs net written premiums, and catastrophic waster losses vs net written premiums. To smooth out variability in annual losses, a 5-year moving average is used in the charts.
Other factors affect risks and losses. Urbanization is a key factor increasing runoff and risks and this has been documented in key case law in Ontario (see previous post with factors). That is, hydrologic stresses increase due to the expansion of urban areas and the intensification of development within urban areas. Other factors include hydraulic constraints in infrastructure systems that can degrade over time - these include natural factors such as blockages of sewer pipes due to build-up of calcite, sediment, roots, FOG (fats, oils, grease), or engineered modifications to collection systems that hold back wastewater flow during wet weather to prevent spills in watercourse - these modifications can in some cases aggravate back-up risks in the wastewater collection system.
Factors such as increasing rain intensity and frequency have been suggested by some however, Environment and Climate Change Canada data (see previous post on version 2.3 Engineering Climate Datasets, and new version 3.0 datasets), numerous regional studies (see compiled engineering and research reports), and the CBC Ombudsman findings (see January 2019 findings on extreme storm reporting), supported by Environment and Climate Change Canada data, all indicate no change in extreme rainfall.
Also see previous post - Catastrophic Losses in Canada - Have Flood Damages Increased Significantly Or Have Changing Data Sources Affected Trends?