Oceans Rising

The apartment where we have spent the last five winters in the Dominican Republic (DR) is right on the ocean. Here the beach very gradually slopes into the water and we have observed over the years that the high tides have been creeping higher and higher. It has been so gradual that we seldom remark on it but this week we had a storm and that really opened our eyes. The pictures tell the story. The one on the far left was taken in 2008 and shows our building probably at low tide with the flags flying in front of it. The picture to the right of it was taken at low tide a couple of days ago after a storm with high waves had washed away much of the sand.

Shocked by the evidence, I checked to see how much the ocean has risen ever since the ice at the poles began to melt and it is only 20 cm. or 8”. That’s not much! I thought it would be more?

It turns out that most of the ice at the North Pole is floating because there is not much land there. When water freezes it expands a little and floats and when it melts it shrinks back to the original volume of water it was made from and doesn’t add a drop of water to the ocean.

At the South Pole the situation is different – the ice sits on the huge continent of Antarctica and much of it is 2.7 kilometers thick! That means its surface is at an altitude of around 9,000 feet where it’s so cold it won’t melt. A lot of what does melt at the edges is replaced by snow and it will take a long time before the incredibly huge quantities of frozen water to add significantly to flooding.

So how fast is the ocean rising? With global warming, the rate has increased to but a little over one inch in 10 years. That sounds manageable but actually it's an enormous amount of water and, with storms hurling that extra water at our shores, it's causing more and more erosion. If you look at the pictures, that's what we are actually seeing at our winter haven here. Rie