What chaos there has been in south-east Europe. Temperatures last week soared high into the 40s over a vast region that includes Italy, the Balkan Peninsula, Greece, Bulgaria, Romania and Turkey.
Here and there the thermometer edged its way towards 50, and power cuts followed the extreme demand for air-conditioning. For upwards of 60 people it was much too much, and directly or indirectly, death ensued.
Although records for high July temperatures were broken in many places, extreme heat at this time of year in these regions is more the norm than the exception. Indeed the ancient Romans had an explanation for it. They noticed that for a 40-day period during July and early August, Sirius, the brightest star in the sky and popularly called the "Dog Star", rises and sets with the sun; they assumed that it was the radiant power of this star, added to that of the sun, which provided the extra heat to make midsummer so unbearable. They called the heatwave caniculares dies, or "the dog days".
But we do not have to seek a supplementary extra-terrestrial power source to explain these recent happenings: the cause was clear on the weather map. Just as severe storms are associated with low pressure, heatwaves come when the pressure is relatively high. In this case the immediate cause was an anticyclone over the eastern Mediterranean. Air moving clockwise around it was first wafted westwards along its southern flank over the hot-plate of the scorching sands of the Sahara, through Libya and Tunisia; subsequently the air moved northwards across the sea and then eastwards along the top of the high over Italy to the countries of south-eastern Europe.
The African heat already in the air was augmented by clear skies throughout the region, which allowed the noon-day sun to raise the local temperature still higher.
Temperatures of the kind experienced last week in southern Europe are not known in Ireland. The highest temperature on this island since instrumental records began about 150 years ago was 33.3, recorded at Kilkenny Castle on June 26th, 1887. Indeed it is very rare for the temperature here to exceed 30 degrees. Even in southern Europe, temperatures in the high 40s are unusual, and 50 is high enough to be considered freakish. But it can sometimes be exceeded in the Mediterranean basin. It was there that the highest air temperature ever recorded on this planet occurred on September 18th, 1922, in a place called al'Aziziyah in Libya; the official temperature that day reached 58 - a clear world record, both before and since, and yet to be equalled despite our current fears of global warming.