Sir,

Sea levels are not fixed - as the Earth’s plates move around over millions of years, sea levels rising and falling hundreds of metres by ice melting and erosion by glaciers retreating by the Earth’s natural temperature changes.

Global warming and cooling is not new, it has been happening since Earth was formed. Evidence can be seen of the past in the geology of the landscape today.

At one time, South Wales was a rain forest and as the earth cooled here it became a bog full of rotting trees drying out and forming peat and brown coal.

Lignite sediment from erosion covered over the area causing pressure on the lignite and in millions of years it changed to the coalfields which we know today.

If you look out from the end of Tenby’s White Lion Street towards Monkstone, the cliff tops were once the sea bed.

As the Ice Age came, the sea lowered and the sea bed became exposed and started drying out, forming huge sand drifts at Poppit, Newgale, Dale, Freshwater West and East, Manorbier, Tenby and Pendine.

These dunes were larger than today and reached out over 120 metres seawards.

The old South Beach sea outfall and the remains of the Penally outfall were the extent of the dunes in the mid 1800s and a military small arms range was built 100 metres wide from Giltar by 900 long side - completely eroded by the sea making its way into what is now the remains of the dunes.

Because the sea is rising and Cornwall and Wales are sinking by half-an-inch every 100 years, erosion is part of Earth’s life cycle, creating various gases and oxygen to sustain life forms.

The groynes on Tenby’s South Beach were erected without any foundation of any sort. Considering that the South Beach is over a mile long and the groynes were approximately four metres deep by 10 metres long, it was a lost cause as the sea ripped them apart and left them on their side.

Nature made the dunes and nature in time will reclaim them.

Time and tide wait for no man.

Trevor Hallett,

Tenby