According to scientists employing atomic clocks, the Earth’s rotation was 1.59 milliseconds under 24 hours recently. Apparently June 29, 2022 was the Earth’s shortest day since its rotational history began to be recorded. Up until the last two years, the Earth has been spinning more slowly and taking longer to complete a full day.
In the last few years, the Earth has increased its rotational spin:
One explanation of the spinning anomoly is the Chandler wobble:
“One team of researchers thinks that the shortening of days could be related to a small irregular movement in the Earth’s geographical poles and its axis of rotation that shifts them by a minuscule amount across its surface called the ‘Chandler wobble.’
‘The normal amplitude of the Chandler wobble is about three to four meters at Earth’s surface, but from 2017 to 2020 it disappeared.’ HSE University associate professor Leonid Zotov told Time and Date.”
It is unlikely that a negative leap second will be required to keep civil time measured by atomic clocks in sync with solar time according to Leonid Zotov:
“I think there’s a 70 percent chance we’re at the minimum and we won’t need a negative leap second.”