Climate change caused by human activity may be affecting global timekeeping as the melting of ice sheets in Greenland and Antarctica slows the Earth’s rotation, the latest research says.
Scientists have established the slowing effect of ice melt by measuring the changes in Earth’s gravity field, which have been recorded by satellites since 1976.
Because the Earth’s rotational speed is not constant and moves out of line with clocks since the world adopted co-ordinated universal time — or UTC — in the 1960s, an extra second has been added periodically. This is known as a “l(fā)eap second”.
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