TimeAndDate, a specialist time zone company, has announced that 2021 is the shortest year on record and that 2022 could be even shorter.
Graham Jones, the company’s science officer, told Newsweek that 2021 will be 65 milliseconds shorter than the average year, “the shortest year on record.
Jones said this is due to changes in the speed of the Earth’s rotation. Normally, the average day is 86,400 seconds, but each day is not precisely the same length. Even very slight deviations in the speed of the Earth’s rotation can cause subtle changes in the length of the day that become longer or shorter, just not felt.
“Carefully measure the length of each day of the year, and you’ll find that some days are longer and some days are shorter.” Jones said, “One of the key factors that affects the length of the day is the orbit of the moon, and the distance of the moon from the Earth.”
Jones said this still has a short-term effect on the speed of the Earth’s rotation, while other factors such as the wobbling of the oceans and the movement of the Earth’s interior have a long-term effect on the speed of the Earth’s rotation. We do not know enough about these factors, so it is very difficult to predict the speed of the Earth’s rotation, at best, can only predict the situation six months later.
Jones added that the record of geological evolution, the observed record of solar eclipses, shows that the speed of the Earth’s rotation should gradually slow down in a long time range and lead to a gradually longer year.
“Interestingly, the Earth’s rotation speed suddenly accelerated last year (2020).” Jones said, “Although it has fallen back after the acceleration, the Earth is still rotating faster this year (2021) than last year, so next year (2022) will be slightly shorter from what we’ve seen so far. But it’s not certain yet.”
The data comes from the International Earth Rotation Service (IERS), an agency that provides a global reference standard for time. It is this agency that determines whether global time needs to be adjusted by adding leap seconds based on changes in the speed of the Earth’s rotation time.