Waves of heat

Suddenly these phenomena are all over the news. Every day we read about somewhere that is getting record breaking temperatures and the effect it is having on people's lives there. Not just people either. A whole sea, the Mediterranean, is now experiencing temperatures way in excess of what we might expect in our local swimming pool and this can only be having a negative impact on the creatures that normally live within it. As usual, of course, there is something of a disconnect between the negative health impacts that this brings and the advertisements encouraging those that can afford it to take holidays in these places. Surely one would never deliberately travel to a place which is experiencing temperatures exceeding forty degrees Celsius... but many do. We are bonded into a way of life where a holiday in the sun is a desirable and this enables us to ignore anything negative about the place we would be travelling to.

So what is this thing, the heatwave. It turns out that this depends upon where you are. The definition starts by setting a baseline maximum temperature for every part of a country and when this is exceeded on three consecutive days then that is a 'heatwave'. Here in Scotland the threshold is a mere twenty five degrees whereas people living in London must endure twenty eight degrees for three days before they can call it a heatwave. None of these are anywhere close to the forty degree heat that Spain has been getting but then each of us has our own threshold and ours is quite enough for us to live with.

When we first moved to the west coast of Scotland we sort of knew what we were going to be letting ourselves in for in terms of weather. That it is a good place to erect a wind turbine or two is a clue to one of the main weather features common to the area we now live in. There is an ocean lying to the west of us, the Atlantic, with no land to slow down the wind before it reaches us so we are used to feeling its strength, our houses being built to cope with this. The air it brings our way is moist and relatively warm, coming as it does from the south west, so our climate is less extreme, both in summer and winter, than one might expect at our latitude. Rain is a constant friend, in quantities which might cause floods elsewhere, but here the steep wooded hills absorb much of it as well as providing a short runoff into the sea. We have had long dry periods of late which makes the vegetation vulnerable to fire but beneath the ground the moisture stays captured so the recovery time is always short. Our clean air, freshly scrubbed after its journey across the Atlantic Ocean, means the sun can be fiercely strong when it shines on us but the breeze is rarely absent so we would normally miss the extremes of heat that others might get.

It turns out, however, that this natural pattern of weather can go wrong. As I write the sky is completely cloud free in all directions, of itself quite unusual here, and the breeze has almost deserted us. What there is of it arrives from a south easterly direction, having crossed a land which is already scorchingly hot, so the cooling benefit is lost completely. We hide indoors, curtains closed to shut the sun out, and keep ourselves topped up with fluids as per the heatwave guidance. This is not normal for us and we know something has gone wrong when yet another day follows the same pattern of exceptional heat. We cannot complain, of course, since these temperatures are far from what others have to contend with when they arrive at their Spanish holiday destination but being locked into such a static weather pattern even for just a few days is rare here so it brings home to us how the world is changing, even for us.

Then suddenly everything changes. Our last day of scorching sun is accompanied by a cooling breeze, the first indication that a change might soon arrive. And so it does. Two days later you wouldn't know there had ever been a heatwave. It is cool enough outside to need a coat and the rain comes down in bucketfuls, drenching the ground, refilling the pond and watering the apple trees which were starting to whinge about having too few leaves to shade their (few, tiny) apples. The constant exhaustion we have been feeling gradually diminishes and we can start planning more energetic activities instead of staring at the TV in a living room darkened by the drawn curtains. Out of the blue I get an invitation from a friend to go sailing in his Mirror dinghy, something that sounds quite attractive now I know I won't get heatstroke any more.