Ebb and flood

Continually twice in a day
the oceans come and go.
It is the moon, so people say,
which draws the water flow.

The power of the moving tide
keeps us on our toes,
we wouldn’t dare put it aside,
respect how far it rose.

And when sea levels go on rising
the flood builds higher waves.
So engineers are now advising
to watch how it behaves.

The sea will claim all land that’s low
unless our dykes do grow and grow.