Wednesday, 12 August 2015

Coastal Erosion - Part One

Our coastline isn't static
And the change can be dramatic,
Durdle Door, west Lulworth, Dorset
For whole chunks of cliff can suddenly collapse.
Many factors are in play,
Which can cause rock to give way -
Like how soft it is and whether there are gaps.

Pounding waves can be invasive,
And churned up sand's abrasive,
The acidity of water can liquesce.
Any stone containing lime
Will dissolve if given time,
Which is why our seaboard's often under stress.

Attrition and corrosion
And corrasion cause erosion.
Old Man of Hoy, Scotland
All are mainly due to how the sea behaves.
Its habitual predation
Can result in the creation
Of landforms - arches, tunnels, stacks and caves.

England's North Sea coast
Is affected more than most:
Holderness is just soft boulder clay.
Winds create a longshore drift,
Which material will shift.
Five millimetres vanish every day.

Mappleton's a village
Which the sea had sought to pillage:
Clashach Cove, Moray Coast
The erosion rate just there was even faster.
Two million was expended
So the place could be defended:
Its inhabitants no longer face disaster.

But an engineered creation
Aimed at damage limitation,
Will often have the caveat "Beware!"
One location it protects
But there may be side effects,
By aggravating what occurs elsewhere.

So where the coast is battered
Land is worn away or shattered,
And human beings too have played their part.
Sand and gravel from one bay,
By the ton was dredged away
To extend some docks, which didn't prove that smart.

With its ever lowered beach,
Now Hallsands is in reach,
And its residents are driven to complain.
They fear their homes are fated
But the digging's unabated:
Only later does the company refrain.

There's a strengthened new sea wall,
But this doesn't help at all
And proves itself quite easily traversed.
Now there's not much to be seen,
For in 1917,
The elements combined to do their worst...


Ⓒ Maggie Ballinger 2015


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