© Ed Hoskins
The reversion to a true ice age is almost overdue.
The last millennium, 1000AD - 2000AD, has been the coldest millennium of the entire current Holocene interglacial.
Each of the notable high points in the Holocene temperature record, (Holocene Climate Optimum - Minoan - Roman - Medieval - Modern), have been progressively colder than the previous high point.
For its first 7-8000 years the early Holocene, including its high point known as the "climate optimum", temperatures have been virtually flat, with an average drop of only ~0.007 °C per millennium.
But the more recent Holocene since a "tipping point" at around 1000BC, 3000 years ago has seen temperature fall at about 20 times that earlier rate at about 0.14 °C per millennium .
The Holocene interglacial is already 10 - 11,000 years old and judging from the length of previous interglacial periods, the Holocene epoch should be drawing to its close: in this century, the next century or this millennium.
