The Environment Secretary, Hilary Benn, warned this week that climate change will affect all our lives after a report stating a two degree rise in average temperature by 2040 is now unavoidable, and it could be up to eight degrees by 2080.
We are then told to plan and build better flood defences.
Read Mark Lynas' book "Six Degrees" and you will see there a grimly sober, well-sourced assessment that by six degrees, there will be nothing left to defend from rising seas.
A six degree increase across the planet will extinguish life as we know it: apart from in the polar regions (possibly not even there), the ecosystem that human and most forms of animal life depend on will have collapsed and the atmosphere will be barely breathable.
It may seem a huge change for a relatively small increase in temperature, but the biosphere that sustains life is thin in the extreme - not only is it a tiny layer between the planet and outer space; it is also sustained by an extremely precarious balance in nature. It has been disturbed naturally in the past, though the changes then have nearly always been over centuries and millenia, not the decades of the current changes.
We have it in our gift to avoid this: but if we don't change, if we don't move to a fairer society based on local, sustainable production and moderate our consumption, we face the prospect of making this the final century not only of our civilisation, but of our very species.
Mr Benn needs to think about more than flood defences.