The four Aces represent the four cardinal points, the four seasons, respectively the four major astronomical events, the two equinoxes and the two solstices.
The Ace of Wands represents the Spring or March Equinox, The Ace of Cups represents the Summer or June Solstice, the Ace of Swords represent Autumn or the September Equinox and the Ace of Disks represent the Winter or December Solstice. Read more The four Aces