Nobody could fail to remark how warm it was at Christmas. It wasn’t particularly sunny – compared to four years ago when we has Christmas lunch on the beach in bright sunshine. But the sun wasn’t there this year: instead we had wet and cloudy with a warm airstream.
This was, of course, reflected in the sea temperature which, for some time now, has been at or near the maximum ever recorded. As I write, the maximum recorded for Salcombe today was 11.3°C and the temperature is actually 11.2°C. If you are a winter sea swimmer, that makes life a bit easier but there is a downside. For the world is seeing a huge amount of sea water warming. Three years ago the level of sea warming was estimated to be the equivalent of exploding one atomic bomb every second as the seas were estimated to be absorbing around 90% of climate change energy.
Hot seas produce stronger winds, bigger waves and milder climates. They also melt polar ice. In the northern hemisphere we may have been unduly relaxed about that. Much of the Arctic is frozen sea and if that melts, and we have all seen pictures of polar bears perched precariously on small floats of ice, this doesn’t affect the level of the sea that much. The hazard in the northern hemisphere is Greenland, 600,000 square miles of ice 7000ft thick. But as long as that stays on land, even though the ice is now melting quite rapidly, it won’t much affect the sea level, or only relatively slowly.
It is down south where the action is. Some readers might remember that, 20 years ago, the Larsen-B glacier, 1,200 square miles of ice 200 feet thick, slipped into the sea and everyone was astonished how quickly it broke up and melted away. But now something far more dramatic is looming. The hugely bigger Thwaites (or Doomsday) glacier, one of the largest in the world and about the size of Britain, looks to be breaking up. When it does, which now seems possible within the next few years, this will raise the sea levels everywhere by half a metre or more. We will notice that half a metre in Salcombe, Frogmore or South Pool. But that is not all: the Thwaites is believed to be holding back other huge glaciers which could shortly follow suit and they could raise the sea levels across the world by several metres. It is a small world.