"There is more land in the northern hemisphere than the south," Holme said. "In northern summer, the trees get leaves, this means that mass is moved from the ground to above the ground — further away from the Earth's spin axis.” The rate of rotation of any moving body is affected by its distribution of mass. When an ice skater spins on the spot, they rotate faster when their arms are tight to their chest, and slow themselves down by stretching their arms out. As Earth’s mass moves away from its core in summer, its rate of rotation must decrease, so the length of the day increases, Holme explained.
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... well God Damn.
Live Science
Earth is going to spin much faster over the next few months — so fast that several days are going to get shorter
Differences in the gravitational pull between the Earth and the Moon will make July 9, July 22 and August 5 unusually short.
