In recent years, Earth’s rotation has accelerated due to dynamics in the planet’s liquid outer core, raising the possibility that scientists might soon have to abolish a leap second. However, a new study suggests that the impact of global warming on the polar ice caps is counteracting this acceleration and will likely delay the need to abolish a leap second until 2028 or 2029.
Polar Ice Melting Alters Earth’s Rotation and Universal Timekeeping
A study published in the journal Nature indicates a serious effect closely linked to polar ice melting and the rotation of planet Earth. The culprit behind this phenomenon is unmistakably human-induced global warming. According to experts, humans are soon to lose a second of their lives due to this phenomenon. Earth’s rotation determines the hours and minutes that make up a day. Although rotation isn’t classified as “constant,” it can change depending on what happens on the surface and, more specifically, in its core.
The increased melting of ice in Greenland and Antarctica, measured by the gravity of one of the satellites, has decreased Earth’s angular velocity more rapidly than before. Earth’s rotation appears constant, but its speed undergoes many small fluctuations unnoticed by most of the planet’s 8 billion human inhabitants.
Earthquakes, volcanoes, tidal forces, and wind patterns can affect the speed at which the world spins, and now a new article suggests that the redistribution of mass from the poles to the rest of the world’s oceans (also known as polar ice melting) is slowing down global rotation. Interestingly, this is delaying an unprecedented moment in history: the first abolition of a leap second. The deceleration counteracts the acceleration.
This fact could be alarming as it poses “an unprecedented problem for computer network synchronization and may require changes to Coordinated Universal Time (UTC) to be made earlier than expected, as a second may not seem like much, but in today’s interconnected world, mistiming could lead to enormous problems.
An Intercalary Detail in Earth’s Rotation
Since 1972, scientists have added 27 leap seconds to the clock, sometimes with disastrous results. Website failures, technology service blackouts, errors in airline reservation systems, and financial market instability are just a few concerns, and companies like Google and Meta have even devised a method called “leap smear” that essentially distributes the added second throughout the day. It remains to be seen what could happen when scientists subtract a leap second.
This story was written in Spanish by Perla Vallejo in Ecoosfera.
