The last millennium, 1000AD – 2000AD, has been the coldest millennium of the entire current Holocene interglacial.
I’m including most of Robert’s post. Read all of it.
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.
But the slight beneficial warming at the end of the 20th century to the Modern high point has been transmuted into the “Great Man-made Global Warming Scare”.
The recent warming since the end of the Little Ice Age has been wholly beneficial when compared to the devastating impacts arising from the relatively minor cooling of the Little Ice Age, which include:
• Decolonisation of Greenland
• Black death
• French revolution
• Failures of the Inca and Angkor Wat civilisations
• etc., etc.As global temperatures have already been showing stagnation or cooling over the last nineteen years or more, the world should now fear the real and detrimental effects of cooling, rather than being hysterical about limited, beneficial or probably now non-existent further warming.
Warmer times are times of success and prosperity both for man-kind and the biosphere.
One should think of the Holocene interglacial epoch as a whole with its progressively cooler and cooler warm episodes:
• the Holocene Climate Optimum
• the Minoan warming
• the Roman warming
• the Medieval warm period
• recent modern warming, 1975 – 2000.For example during the Roman warm period the climate was warmer and wetter so that the Northern Sahara was the breadbasket of the Roman empire .
According to the Ice Core records, each of these successive Holocene warm periods have been cooler than the one previously and a tipping point towards accelerated global cooling occurred at about 1000BC.
The coming end of the present Holocene interglacial will in due course again result in a mile high ice sheet over much of the Northern hemisphere. As the Holocene epoch is already about 11,000 years old, the reversion to a true ice age is almost overdue and would be the real climate catastrophe.
With the present reducing Solar activity, significantly reduced temperatures, at least to the level of another Little Ice Age are predicted for later this century .
Whether the present impending cooling will really lead on to a coming glacial ice age or not is still in question.