Beating off the waves – Sinking or migrating?

It opened up new views of the Maldives to me.  The story of how they were fighting off sea level rise was a familiar one to me – I even had worked on a project at university in the 1980s exploring the various options.  My solutions there had been rather clunky – using material from the inside of the atolls to build up the outside, more sea defences, different land uses.  Now I was here I could see that all of these had been tried and more.  But my view was that every island was the same and uniformly affected by sea level rise.  What I now saw was that while there was that inexorable pathway to submergence from sea level rise, the short term effects of that were affecting one side of the island more than the other.  Having a small amount of rise might not impact the coast, but if a storm came in, the accumulation of larger waves on top of an incremental change in normal levels could be devastating for a vulnerable coastline.  And that is what I had seen on the eastern side of the island.  When the sea is benign there is not issue, but if a storm hits serious erosion can happen overnight – especially if trees topple and the loss of roots shakes free lots of sand and soil.

But what appeared to be happening is the island is migrating.  Much of the material that was removed from the east was migrating round to the west, and the island is gently moving towards the centre of the atoll.

The long term dynamics must be more complicated that this and it might take many generations for the island to move a long way, but it was undeniable that most of the slack, the dune and the beach were relatively recent additions to the coral island.  The upshot is though that given the small size of these islands and some with a high population density, there is not enough room for leaving the usual setbacks that minimize damage to property in storms.

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Is the island stable, eroding or migrating?

Beating off the waves – A surprise on the leeward side

I cursed myself for not checking that pocket.  I had been so meticulous with every other item; the one thing I was carrying that was worth a lot I had forgotten.  Well there was nothing to be done.  I caught up with the rest of the walkers but for the time being did not mention anything about the phone to them.  We had work to do and there was not time to think about my stupidity.

The south coast was a nice stable sandy beach and as we headed westwards the house plots diminished – some were not even built on.  And there were open communal spaces here with pathways down to the coast.  The vegetation was lush and thick and held the land together.

This western end of the island, away from most of the settlement, was also where their refuse dump was.  The system was easy – each household would truck or walk down with their rubbish and leave it.  There was a modicum of sorting going on, areas where metals and tyres were stacked, but for the most part everything from household waste to paints, builders rubble, and so much paper and plastic, was dumped in a mixture either side of a pathway.  And small smouldering fires rose from these piles to try and reduce it down.  The councillors were aware of all the problems of poisonous pollutants entering the air and the precious fresh water lens below their feet, but they shrugged their shoulders and said “where else can we put it”.

We ended up at the western tip of the island, and here the whole island dynamic came to its unexpected conclusion.  We traipsed through a very pleasant nature reserve – some slacks where water came to the surface and had produced a haven for frogs, dragonflies and marsh loving plants.  The community had set up a couple of walkways through, a picnic area and signage to explain what you were finding.  Like a park anywhere in the world but beautifully laid out in miniature here on this tiny island.  The slacks were behind the highest point on the island – a small series of sand dunes that towered above us to the height of about…. six metres.

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You have to put the trash somewhere.

On the far side of these was a wide sandy beach, which was more of a triangular shape than running parallel to the coast.  This was the answer to what happened to the material scraped off by the waves on the east end of the island.  It gradually washed in the longshore currents to this end of the island and since the water was less active was actually accumulating here, hence the sand building up to its triangular apex.

Return to Cayman – Ridge to Reef sightseeing

The walk gave us a chance to explore the landward side of Grand Cayman.  I enjoyed it a lot – I always like scrambling about the interior of Caribbean islands.  While most tourists will stick firmly to the beaches, resorts and towns, these patches of woodland are the last remnants of how these islands must have looked in the pre-Columbus era.  Particularly in these drier islands, the vegetation has a fragility which is all too easily disturbed, but get down in amongst it and you see the resilience and adaptability of species for coping with irregular rainfall, thin soils and on ferociously incised geology.  I loved Ghut running in BVI  – the temporary river channels up and down the mountain were often the best ways to walk through the forest, the periods of heavy rain flushing aside the soil and vegetation to make a clear path in the dry season.

But of course, what one thinks of when you hear the word Caribbean is sand sea and sun, and for our final night on the island, we were taken on a sunset cruise across the North Sound.  Most of the delegates boarded two catamarans and headed out into the open water.  It was your traditional booze cruise, we’d help ourselves to a cocktail or beer and settle down on the benches or on the net straddling the two hulls.  Everyone was so relaxed and chatty the time passed quickly.   Here,  rarely in the Caribbean, we were at sea but almost surrounded by island and the sun sank below the mangroves to our west, picking out the straggly branches of their canopies.  The mangroves had been bashed about by the hurricane that had made me evacuate the year before and , like many trees on Cayman, were taking time to regenerate.

In semidarkness we alighted at a dock close to one of those magical restaurants that exist across the Caribbean.  A welcoming building opens up on to the sand, the tables perfectly set on the beach (how come they never get sand on every item), lights wound up the tree trunks and set out on poles in the shallows to shimmer against the darkening surface.  We had a great party there.  Then it was socks and shoes or sandals off again and wade back to the boats.  We sat glowing as the catamarans chugged us back over to the hotel; no better way to spend a night in the Caribbean.

A tale of two swamps -So far from the ocean…

We had one last stop that day.  To the north of Samfya was a resort hotel and we had seen from the main road that it sat above sand dunes.  We decided to investigate further and took a turning off the tarmac just at the entrance to the town.  We surfed over the crest of these dunes and dropped under the hotel to a beach bar.   The sand was whiter than by our own hotel; you could have been in the Caribbean.  A guy was sweeping the sand clear of detritus from the nearby trees, preparing the beach for weekend trippers and locals.  I’m not sure I wanted to enter the lake myself as there were a few water snail shells around and I was not keen on contracting bilharzia.  But the scene was alluringly beautiful and surreal.  This beach was the westernmost point of the open water of Lake Bangweulu and lakewashed sand from the rest of the basin must be blown here on prevailing easterly winds, particularly in the dry season when the lake is low and sediment exposed.  Over the years the sand has been whipped up into 20m dunes as if you were on the coast or desert plains.

These bizarre natural phenomena in amongst the marshland and rolling agricultural land are not protected though, and sand is a valuable building commodity, so it is no surprise that the leeward side of the dunes are being excavated at an alarming rate.  But the beachside has an elegant beauty all of its own.