Weather-ology: The Earth on Fire
Long before modern science began to understand the processes that create our weather, people made up their own explanations. Many of these accounts were fantastic in nature, with evil or benevolent gods, monsters, and spirits controlling the elements. In this series, we’ll explore some of these ancient myths and share the science behind them. Weather + mythology = weather-ology!
Earlier in this series, we met Helios, the Greek Sun god said to drive a chariot led by four fiery horses across the sky each day. One of the most popular myths about Helios concerns his mortal son, Phaeton.
The boy, whose name meant “the shining one,” had grown up without ever knowing his father. When his mother finally told him the truth about his divine parentage, he did not believe her, so she encouraged him to make a journey to his father’s palace in the east. After a long and arduous journey, Phaeton found his father, who was so overjoyed to see his son that he swore by the river Styx (the most sacred oath one could give at that time) he would grant Phaeton any one thing he wished. Helios immediately regretted his offer when his son named his heart’s desire: Phaeton wanted to drive his father’s chariot. Though the sun god tried to talk him into wishing for anything else — even the god Zeus was unable to control Helios’ four steeds — Phaeton was resolute. Having sworn a sacred oath, Helios was bound to it, so he anointed his son’s head with magic oil to keep him from being burned by his fiery chariot and prepared his horses for the day’s work.
As soon as Phaeton took the reigns, the four horses could tell their new driver was not as strong as their master. They bolted, dragging the hapless youth in the chariot behind them. First, they carried the chariot too high, so that the Earth grew cold and dark. Then they dropped down too close to the Earth, burning everything in their path. Crops withered and died, stream beds dried up, the Earth baked. Deserts formed across much of Africa.
The people called out to the gods to help them and Zeus was finally forced to intervene. He struck the chariot down with a lightning bolt, killing Phaeton and sending him tumbling into the river Eridanos. Helios was grief-stricken and blamed Zeus for the loss of his son, but Zeus insisted it had to be done for the sake of all life on Earth.
The gods laid Helios’ son to rest, marking his grave with the epitaph, “Here lies Phaethon who drove the Sun-god’s car. Greatly he failed, but greatly he dared.”
The Greeks invented the story of Phaeton to explain heat waves, drought, and the existence of deserts. When, as has happened this year throughout the southern half of the United States, the heat index rises and rain does not fall, it can be easy to believe that the Sun has moved closer, baking everything in sight.
Of course, today we know that hot, dry weather is caused by high-pressure systems moving into an area. The high atmospheric pressure prevents water vapor from rising up and forming clouds. The lack of clouds allows even more sunlight to reach the Earth, warming things up even further. High-pressure systems are incredibly stable, and can become self-perpetuating. Usually, these fronts are eventually broken up by low-pressure fronts, bringing cooler air and rain. Sometimes, though, the weather conditions are just right to keep a high-pressure system in place for several weeks or even months. When that happens, the result is a drought.
This can happen for any number of reasons. Jet streams can work to hold a high-pressure system in place. A La Niña — periodic cold-water currents in the Pacific Ocean — can prevent low pressure systems from forming. Or, as is the case in desert regions, mountains can prevent water vapor from the ocean from reaching certain inland areas.
Thankfully, most droughts do eventually end, as low-pressure fronts move in and bring rain. And, as when Zeus struck down Phaeton, the lightning is usually a welcome sound to those below.