Climate Doomsayers Ignore Thousands Of Years Of Historical Climate Trends
Predictions from climate doomsayers reveal an embarrassing ignorance of a capricious geological history shaped by natural forces too powerful for human control and too complex for meaningful forecasts. [some emphasis, links added]
We are living in the warmth of an interglacial period known as the Holocene Epoch, which began about 11,700 years ago.
It followed a frigid span of nearly 90,000 years, during which thousands of feet of glacial ice covered Canada and the northernmost parts of the region that would become the U.S. Temperatures were 11 to 14 degrees Fahrenheit below the current average.
The relatively benign Holocene of nearly 12 millennia has been punctuated by intermittent temperature changes, including 10 warming periods, counting our current one. The most recent cold era was the Little Ice Age, from about 1250 to 1850.
Climate alarmists treat the “preindustrial” era before 1850 as their starting point for measuring modern temperature, without noting that the period falls within the last gasp of the Little Ice Age.
Their hysteria and the climate policy they promote are based on a temperature record that begins during a period of unusual cold and on a subsequent warming of a modest 2.4 degrees Fahrenheit over the last 175 years.
If the temperature record were expanded to include the warmest parts of the Holocene, the same planet would appear to emerge from an intermediate deep freeze. Research published in Nature shows that marine sediment cores place peak warmth in the first half of the Holocene interglacial, between 10,000 and 6,000 years ago.
Biomarker records from sediment cores in the Chukchi and East Siberian Seas, published in the Journal of Quaternary Science, show minimal sea ice during the early Holocene, short-term fluctuations through the middle Holocene, and a marked expansion of ice over the past 4,500 years.
Chukchi Sea reconstruction and the broader Arctic picture both trace an ocean that carried far less ice when no factory existed anywhere on Earth. The ups and downs of modern Arctic ice are wobbles inside a range sustained for more than 11,000 years.
Two thousand years ago, Roman farmers grew grapes and grains at higher latitudes and altitudes that later generations had to abandon as the climate cooled.
During the more recent Medieval Warm Period, about 1,000 years ago, Norse settlers lived in southwestern Greenland for close to five centuries, grazed livestock, harvested barley, and buried their dead in churchyard ground that later froze solid and stayed frozen.
Tree stumps continue to appear from beneath retreating glaciers in the Alps and the Canadian Arctic, rooted in soil that carbon dating places in the warmth of the middle Holocene.
Then came a temperature decline accompanied by horrific consequences for humanity. The Little Ice Age closed Alpine passes, swallowed farms, killed harvests across northern Europe and emptied Greenland settlements. Rivers that had not frozen in human history became sites of ice fairs.
Two independent temperature reconstructions, one drawn from Greenland ice and the other from ocean sediments off Indonesia, sit 9,500 miles apart yet track each other closely, recording a fall of around 5.4 degrees Fahrenheit between the Holocene peak and the coldest of the Little Ice Age.
While broad historical climatic trends can be identified, predicting the future with confidence is tricky at best. Ocean oscillations in the Pacific and Atlantic redistribute heat on decadal and centennial timescales that no one can predict from first principles.
Solar output varies. Volcanoes intervene on no schedule. Cloud behavior, the single largest uncertainty in every atmospheric model, responds to all of it. These assemblages of water vapor and aerosols act both as insulators against nighttime heat loss and as reflectors sending sunlight back to outer space.
All are mighty forces, along with many others, that operate irrespective of human activity, whose effects are negligible on the grand scale of a climate system of practically infinite complexity.
In the end, we know that warmth is better than cold for human flourishing, and that abundant, affordable energy is necessary to build and sustain prosperous societies. In the meantime, the Holocene climate will keep doing what it has always done, and we will know what that is after it happens.
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