There’s confusion over sea level rise and tsunamis, in what you report in your October 22, 2014 issue.
For over two centuries the rate of sea level rise has been averaging about 2 mm/year globally, that’s 0.4 metres in two centuries, fluctuating about that with warming and cooling. That’s orders of magnitude less than climate alarmists predict using their theories that have been dis proven by reality. But crustal plate tilting may be a larger factor, for example sea level relative to land height – which is what matters for building – has actually dropped in some locations in this region. Thus predictions used should be specific to a local area. (Refer to psmsl.org for government sea level data. Long data sets are available for New Westminster, Port Townsend, and Neah Bay, for example. But data has to be examined carefully to see any slow trend, as year-to-year variation is large.) The slow rate of sea level rise should not be difficult to handle.
Tsunamis however are a difficult issue. The concern should be a large change in ocean bottom from an earthquake, near here. The 1964 earthquake in Alaska is not a good reference point, because of the distance over which the wave could spread and the intervening land mass called Vancouver Island. I’m advised that narrow channels increase the height, and that Port Alberni suffered from that in 1964. So risks must be evaluated for probable earthquake locations, type of movement, and specific geography.
The whole subject is a difficult one because rational action requires evaluation and judgement of risk against cost of preventing the downside. Shouldn’t that action be by property owners who will suffer the consequences of being inundated, and of reduced property values in the meantime, not by government?
Of course the blind retroactivity of building rules is typical bureaucratic thinking that has already reduced stock of housing in this area. Bureaucrats can’t even accept surveying errors made over a half century ago that put house setbacks slightly below zoning rules. Bureaucrats lack perspective, they work in isolation and don’t suffer the consequences of their control-freak action.
Keith Sketchley
Saanich
