Rising sea levels and melting ice caps due to human-made emissions could result in the need for a ‘negative leap second’ in 2029, altering global timekeeping systems and highlighting the broader impacts of climate change on Earth’s dynamics.
A recent study published in the journal Nature has revealed that climate change, through human-made emissions and subsequent rising sea levels, is impacting the Earth’s rotation, which might lead to the need for a “negative leap second” to be introduced in 2029. This adjustment would entail subtracting a second from global clocks to align with the changing speed of the planet’s rotation. Duncan Agnew, the lead researcher of the study, compared the effect of sea-level rise on Earth’s rotation to the adjustments in spin made by a figure skater by extending or pulling in their arms.
The phenomenon is predominantly attributed to the melting ice from Greenland and Antarctica, causing a redistribution of the planet’s mass and, consequently, a slight slowdown in its rotation. This change might impact the Universal Coordinated Time (UTC), necessitating alterations in timekeeping systems that are vital for various technologies including computing and financial markets. Since the 1970s, around 27 leap seconds have been added to account for a previously quicker spinning Earth. However, climate change has partially reversed this trend, shifting expectations for the need for a “negative leap second.”
Agnew highlighted the unique challenge this situation presents, as current computing systems are designed to deal with the addition, not subtraction, of leap seconds. The introduction of a negative leap second raises potential risks and challenges for these systems. Consequently, there is an ongoing debate among experts regarding the future of timekeeping and the integration of more precise atomic clocks, which could render traditional Earth-based timekeeping methods obsolete.
António Guterres, United Nations Secretary-General, pointed out broader implications such as displacement and extreme weather conditioned by climate change, alongside the alarming need for action to mitigate human impacts on the Earth’s dynamics. Despite some skepticism, the consensus within the scientific community acknowledges the significance of these findings and the urgent need to address the intersecting issues of climate change, timekeeping, and technological adaptation.
