By Belad Al-karkhey

As February 29 dawns the occurrence of leap years can be represented in calendar confusion and the significance of cultural festivities and traditions.

The often four-yearly occurrence of February 29 will find some people embracing new traditions whether in the form of wedding proposals or decorating birch trees with ribbon.

A number of Australian lovers will take the leap down the aisle to mark the occasion which also holds origins linked to the heart, while others around the world may choose to avoid divorce or marriage altogether in fear of bad luck.

An antiquated Irish tradition has it that women are allowed to propose to men on leap days.

Leap years are crucial for maintaining the accuracy of the Gregorian calendar, associate professor Darius von Guttlen Sporzynski says, but society has made them greater than a mathematical solution to a celestial problem.

“Over time, (leap years) have woven themselves into the fabric of human culture and folklore,” he told AAP.

“This cultural embedding of leap years speaks to humanity’s innate desire to find meaning and pattern in the natural world, even in something as rational as calendar correction.”

Leap years can be traced back to about 2000 years ago when Julius Caesar was inspired after visiting his lover Cleopatra, who introduced the Roman emperor to a Greek astronomer named Sosigenes of Alexandria.

Through Sosigenes’ suggestion of a calendar year following a solar cycle rather than the lunar, the Julian calendar was born in 46 BC – adding an extra day every four years.

Inaccuracies in the maths misaligned Easter dates, but resulted in the creation of the still-used Gregorian calendar introduced in 1582 by Pope Gregory XIII.

Leap years are designed to address the mismatch between our calendar system and the earth’s orbit around the sun, Dr Sporzynski says.

“A misalignment would disrupt not only agriculture and seasonal activities but also the timing of religious festivals and historical traditions,” he said.

Despite the efforts to align more closely with the seasons, the Gregorian calendar used by a majority of the world today is still off by about 26 seconds, according to experts, and will have accrued a full day by the year 4909.

A general understanding a leap years occurs once every four years is a common misinterpretation.

Mathematical rules dictate a year is a leap year if it is divisible by four.

If a year is divisible by 100 but not by 400, it is not recognised as a leap year.