Vulnerable to Flooding

Lots of the local ecologically concerned folk are sharing this news story based on the
Climate Central flood map update using the CoastalDEM® v1.1 digital elevation model. I’m not immune to doing so myself. Combined with the recent devastating floods in the north of England these projections seem to offer a warning from the future that might help leverage local climate action.

I think it’s a useful graphical representation, but that we also must be careful how we use it. These maps are incapable of showing the protection of existing flood barriers – sea walls etc. [The need for a publicly available open map that does is clear and pressing]. In fact, much of the area coloured red is close to sea-level and would already suffer frequent flooding without those sea-walls.

I fear that the blunt instrument of the ‘shocking’ map tends towards disempowering climate alarmism and provides the authorities with an easy response that the map doesn’t take into account engineered coastal defences – keep calm and carry on.

The map is useful, however, if it is accompanied by some emergent questions:

1) Do the current flood defences provide sufficient protection from storm surges when this rise in sea-level is factored in? (the 1953 storm surge was a 1 in  100-years event [i.e. 1% chance in any given year] before climate change was recognized).

2) If not – what would be the cost of ensuring they do and maintaining that protection for the centuries of already locked-in climate change?

3) UK Govt has said “Despite our collective best efforts, we will not always be able to prevent flooding and coastal change happening” and will not commit to nationwide flood protection. For how long are the local flood defences expected to be maintained? What factors will determine whether they continue to be maintained or not? (cost/benefit ratios?)

4) Should low population density areas of coastal farmland, historically recovered from salt-marsh, instead be rewilded to provide ecologically appropriate flood buffers (with biodiversity benefits) through a process of ‘managed retreat’? #ManagedRetreat

Speaking about the major flooding in North, Boris Johnson recently said:

“You’ve got to face the reality that places like this are vulnerable to flooding – we’re going to see more of it,” adding that the recent bout of floods “is not looking like something we need to escalate to the level of a national emergency”.

If (when?) London or the south-east of England suffers a similar degree of flooding the response is likely to be different but the Prime Minister’s words indicate that a certain fatalism about climate change is already baked into government planning. Individuals are expected to recognise their vulnerabilities (and thus responsibilities for becoming a victim of climate change effects) and these type of events should be responded to, adapted to and mitigated by individuals and/or local/regional authorities rather than by national government – the state is already retreating.