We have just lived through what the Met Office calls “a milestone in UK climate history”: on 18^th and 19^th July temperatures reached 40.3 degrees C for the first time on the British Isles. What made this event so extraordinary was that this event was much more widespread than previous high temperatures that were typically recorded only in a few stations. This one, on the other hand, covered an extensive area of the country, from Kent to North Yorkshire and from Suffolk to Warwickshire.

One day later, on 20^th July, when temperatures went back to more or less normal in the UK, I flew to Bézier (since flights to Montpellier have fallen victim to the impact of the pandemic), hoping to make my way by bus and train to my destination. The shuttle bus to take Ryanair passengers to the railway station at Bézier was not operational, en cause: la canicule. After finally making it to the station and getting on a slow train I was then stuck near Sète for over 80 minutes (with no Wi-Fi), en cause: la canicule (to be more precise: fires had broken out along the railway track).

So what is this mysterious phenomenon, the canicule? It comes from Latin canis, meaning “dog”. Canicula means little female dog, dies caniculares means “puppy days”. In German we call them Hundstage, the Italians speak of giorni da cani, just as in Spanish Días de perros, or in Dutch Hondendagen.

But what possible connection is there between our four-legged friends and sultry heat, droughts, spontaneous fires, thunderstorms, and widespread lethargy?

Canicula (also Sirius) is the name of the brightest fixed star, the main star in the constellation of the Great Dog (Canis Major) and located more than eight light years away. It is also, and most importantly, the fifth brightest star in terms of distance from the Sun. It takes about a month from the appearance of the first Dog Star (Muliphein) to the last one (Aludra), when the constellation becomes visible in its entirety. During this period, the brightest star in the constellation of the Great Dog, Sirius, rises and sets with the sun (“heliacal rising”). This is the period during which the hottest weather occurs in Europe.

Apparently, farmers in ancient Egypt, kept a keen eye on the Dog Star, as it announced the flooding of the Nile which made the region fertile. In Mesopotamia (today’s Iraq) the appearance of Sirius was thought to bring about the summer heat.  Today’s meteorologists do not credit the star with any impact on the weather. The fact that the star’s appearance coincides with the sun is not a meteorological, but an astronomical event.

In fact, over the centuries, the heliacal rising of Sirius has shifted by about one month due to the constellation’s own movement as well as the change in direction of the Earth’s axis. As a result, it can now be seen in Germany from 30 August at the earliest, heralding the end of the summer rather than the hottest days. And yet, the term canicule and dog days still stands for the hottest period of the year.

If you are interested, look up Dog day’s on Wikipedia which contains all kinds of fascinating information, including quotations in Greek with a translation into English, about the effects of Sirius on plants, animals, women and men. Including some good advice on what to do and not to do during this time of the year, like abstaining from eating too much, and any exhausting activities…

The Wikipedia entry also mentions that Dog days make an appearance in European literature, such as The Duchess of Malfi, in Dickens’ A Christmas Carol as well as in Watership Down and others.  As to films, the one that springs to mind is obviously Hundstage by the Austrian director Ulrich Seidl (2001), set in a deprived suburb of Vienna, a set of six stories involving individuals or couples who are lost in their depressing daily routines, obviously brought to a culmination by the heat. All played out in shocking, but also quirky and often hilarious scenarios and dialogs (including some difficult to watch sadistic scenes, which certainly in 2001 were considered vulgar and provocative). Most of the protagonists are non-actors, giving the film an uncanny authenticity.

During 18^th and 19^th July apparently the most frequently asked question on Google was “Is it too hot to work?”. Certainly, precautions were necessary, as excessive temperatures can pose a danger to life. Moving slowly, drinking plenty of water, trying to keep cool… It also entailed huge pressure on the NHS and disruption across transport networks.

The question now is: Could there be another canicule around the corner? Chief meteorologist at the Met Office, Paul Davies, forecasts a bit of a break with temperatures more or less back to what we consider normal, but does not rule out another peak in August. So watch out, and perhaps take some cooling comfort in a farmer’s saying in German: “Hundstage heiß, Winter lange weiß” (if the dog days are hot we’ll have a long white winter). Book your skiing holiday now!

And keep your dog (and cat) nice and cool!