Melting glaciers slow Earth's rotation, lengthening days
Increasing temperatures are accelerating the melting of glaciers and ice caps. This directly results in rising sea levels. As Earth's ice cover diminishes, it heats up more rapidly. However, this is not the only consequence of climate change. It appears that due to this, our days are becoming longer.
The issue has been studied by scientists from the Swiss Federal Institute of Technology in Zurich and NASA's Jet Propulsion Laboratory. According to them, as ice masses melt, more mass is redistributed from the poles to the equator, which causes a slowdown in our planet's rotation around its axis.
It’s like when a figure skater does a pirouette, first holding her arms close to her body and then stretching them out. The initially fast rotation becomes slower because the masses move away from the axis of rotation, increasing physical inertia. In physics, we speak of the law of conservation of angular momentum, and this same law also governs the Earth’s rotation – explains Dr. Benedikt Soja from ETH Zurich, co-author of the study, as quoted by "National Geographic".
Over time, the shape of the Earth also changes. Ocean tides influence this, the drift of tectonic plates, as well as sudden earthquakes and volcanic eruptions.
To best assess the rate at which Earth rotates around its axis, scientists have turned to GPS data, cosmic radio signals, and even ancient records of solar and lunar eclipses.
The result? From 1900 to today, climate change has lengthened days by about 0.8 milliseconds. If greenhouse gas emissions do not change by 2100, days will be extended by 2.2 milliseconds compared to the baseline level.
Lengthening of Earth's day. Milliseconds make a big difference
Contrary to appearances, every millisecond is of enormous significance – especially from the perspective of space. It affects GPS systems, is significant for rocket launches and determining the trajectories of probes they launch.
It is also very important for us on Earth to know that the slower our planet rotates, the greater the likelihood of major earthquakes.
