Climate change lengthens days, impacts Earth's rotation
6:23 PM EDT, July 16, 2024
Research published in "Proceedings of the National Academy of Sciences" sheds new light on how climate change affects the rotation rate of our planet. A team of scientists from NASA's Jet Propulsion Laboratory and ETH Zurich discovered that the melting of glaciers at the poles contributes to slowing Earth's rotation, lengthening days at an alarming rate.
The primary culprits of this phenomenon are the massive amounts of water moving from Greenland and Antarctica toward the equator, which shifts the mass distribution on Earth, reports Science Alert. This effect can be likened to a figure skater whose spin speed changes with the position of their arms.
The length of the day is continuously increasing
Although Earth is commonly considered a sphere, it is flattened at the poles and bulges more near the equator. Its shape is not constant—it changes due to tides, tectonic plate movements, and natural disasters such as earthquakes and volcanic eruptions.
Scientists from NASA's Jet Propulsion Laboratory and ETH Zurich utilized advanced observational techniques during their research, such as interferometry, which allows for precise measurement of the time it takes for radio waves to reach different points on Earth. These measurements revealed that the length of the day increased by a few milliseconds compared to the standard measure of 86,400 seconds.
Moreover, although the most significant factor currently slowing the rotation of our planet is the gravitational force of the Moon, the study's authors suggest that by the end of the 21st century, the impact of climate change on the length of the day may surpass the effects of the Moon's interaction. In a worst-case scenario, with unabated greenhouse gas emissions, climate change could cause days by 2100 to lengthen by 2.2 milliseconds compared to present-day observations.
Although these changes might seem invisible to people, they are crucial for space and terrestrial navigation. Earth's precise orientation is vital for communication with spacecraft, such as Voyager, which are beyond our Solar System. Even the smallest calculation error can result in significant deviations over such vast distances.