Death Valley in southern California is unique in two respects: it is the only part of North America where the land is below sea level and it is also reckoned to be the hottest place in the world. The deep gorge is 145 miles long, and is surrounded by mountains that soar to 10,000 feet or more above the valley floor.
The aptly-named crevasse is baked lifeless by a merciless sun and desiccating winds, and its reputation as a hell on Earth was sealed in July and August 1917, when the temperature in the valley measured in the shade exceeded 50 C for 43 consecutive days.
But it was not in Death Valley that there occurred the highest air temperature ever. The highest thermometer reading in the Californian valley was 57C, but this was topped 76 years ago today on September 18th, 1922, in a place called Al'Aziziyah in Libya; the official temperature there on that day touched 58C, a clear world record and yet to be equalled despite our current fears of global warming.
Temperatures like these are quite unknown in Ireland. The highest to be experienced on this island since instrumental records began about 150 years ago was the 33.3C recorded at Kilkenny Castle on June 26th, 1887. Indeed it is very rare for the temperature here to exceed 30 C.
We are similarly immune from very extreme temperatures at the other end of the thermometer scale. Air temperature in Ireland seldom drops below 10C and rarely remains below the zero mark for more than 24 hours.
The coldest spell we have ever experienced seems to have been on January 16th, 1881, when a record value of 19.1 C at Markree Castle, Co Sligo, was bested a few days later on the 23rd, when 19.4 C was noted at Edenfel, Co Tyrone.
The lowest temperatures in the world occur in Antarctica. One's first impression might be that the temperature at the North and South Poles should be roughly similar, but a difference occurs because of altitude: the North Pole is near sea level, while the Antarctic ice plateau averages some 10,000 feet above sea level.
The world's lowest air temperature was recorded on July 21st, 1983 at Vostok, a Russian scientific base right at the centre of the polar ice sheet; the thermometer dropped to 89.2 C. But Vostok is only a temporary installation; the coldest permanently inhabited place in the world is reckoned to be the village of Oymyakon in Siberia, where the temperature has been known from time to time to drop below 70 C.