Our readers could not have failed to have heard about the heatwave presently in existence and affecting much of Europe, North Africa and Central Asia. High temperatures are, in fact, so prevalent in the northern hemisphere this July that they have prompted meteorologists to name this heatwave.
Under the assumption that heatwaves such as this one will be visited upon us with increasing prevalence and violence, scientists in Seville have now begun naming them. This one, called Zoe, will be the first of many, one imagines, to be given a name.
Zoe was named by an organisation called proMETEO Sevilla, a collaboration of scientific foundations and the city of Seville, and she was given a name as part of her inclusion in a new heatwave ranking system. Only the very hottest, longest-lasting heatwaves will be named and, along with the name, they will be accredited a category, between one and three, ranking their severity.
Zoe, the first of her kind, has broken many records already. Britain recorded it’s hottest day, with a 40.3 degree Celsius reading made in Coninsgby, Lincolnshire. In Tunis, Tunisia, a forty-year record was broken with the temperature reaching 48 degrees. In China’s Shanghai Xujiahui Observatory, where records have been kept since 1873, a new record of 40.9 was set on the 13th of July. These recordings have qualified Zoe for category three status.
Zoe’s arrival in Seville, from where she was given her name, followed Spain’s second hottest recorded June. According to proMETEO Sevilla, she poses a serious threat to human health.
Events like these are, of course, the direct result of a warming climate and we can, unfortunately, expect to see much more high temperature records broken in the next coming years. That is, of course, unless we manage to reverse global heating by bringing the worst excesses of our globe’s behaviour under better control.
How does an elephant deal with the heat?
We don’t want this week’s article to be focussed on the doom-mongering element to Zoe’s arrival. Though global heating does pose a significant threat to all of us, the elephant of Eastern Africa including, we’ve done a fair few articles recently on how elephant are likely to be impacted by, and how they may impact, climate change.
For some further reading, you can check those articles out here:
Four ways the African elephant improves life for human beings
Can elephant help sequester carbon?
Climate change and elephant conservation: long-standing drought highlights changing challenge
We want, instead, to have this article’s focus be on the elephant themselves. Wondering whether there was anything we could learn from elephant, in this near-global heatwave, we wanted to take a look at how elephant cool themselves in the hot weather.
Many of the cooling methods used by elephant are very well-known. We’ve all seen photographs and video of elephant cooling in pools of water or mud baths. This is, indeed, one of the activities they’ll partake in in order to cool off. Play, in pools or in mud, has the additional benefit of strengthening social ties and building bonds.
Much has also been made of how an elephant’s ears are well-designed for the dispersal of heat. Their large size makes them very effective as fans which can be used to cool the air around an elephant’s head and shoulders.
The thinness of an elephant’s ears, and that this brings the blood vessels inhabiting there close to the surface, also provides for increased cooling. Looking at the underside of elephants’ ears will make obvious an intricate network of capillaries that bring warm blood into contact with the cooled air around an elephant’s head.
These capillaries allow for this blood’s cooling and can, allegedly, lower the blood temperature of an elephant by about five degrees Celsius.
These things are fairly well-known and may be of no surprise to our readers. What is likely to be less well-known, however, is the fact that an elephant only has pores between its toes. That, therefore, means that it cannot sweat out of most of its skin’s surface area.
This means that the other methods for cooling itself off are essential. Furthermore, this fact, added to by the evolutionary necessity of an elephant’s having such hardy skin, means that the elephant has adapted another, unique means of cooling itself.
An elephant’s hide, which, as we’ve said, lacks the pores found on other mammals, actually becomes more permeable in extreme heat. Research published in The Journal of Experimental Biology found, after measuring the moisture and heat given off of elephant in different temperatures, that both Asian and African elephants’ skin effectively opens up, despite the lack of pores, in hotter temperature.
Scientists aren’t, at present, exactly sure how the permeability of an elephant’s hide works. It does seem changeable but how that works without pores is, as of yet, poorly understood.