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Frank
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What climate crisis?
Past warming has never been driven by an increase in carbon dioxide
Ian Plimer
For more than 80 per cent of time, Earth has been a warm wet greenhouse planet with no ice. We live in unusual times, when ice occurs on continents. This did not happen overnight. The great southern continent, Gondwanaland, formed about 550 million years ago. It occupied 20 per cent of the area of our planet and included Antarctica, South America, Australia, South Africa and the Indian subcontinent. Gondwanaland was covered by ice when it drifted across the South Pole 360-255 million years ago. Evidence for this ice age is in the black coal districts of Australia, South Africa and India.
The breakup of Gondwanaland started about 180 million years ago. About 140-120 million years ago, Australia was joined to Antarctica and enjoyed a temperate climate, had alpine glaciers that shed icebergs into warm seas and plant and animal adaptations evolved to cope with the long periods of winter darkness.
If Antarctica is to lose its ice sheets to end the current ice age, plate tectonics must move the continent northwards or fragment Antarctica into smaller land masses. Parts of Antarctica are currently being fragmented which is why there are more than 150 hot spots and volcanoes in rift valleys beneath Antarctic ice. Plate tectonics must also widen the Bering Strait to allow more warm Pacific Ocean water to enter and warm the Arctic.
Australia separated from Antarctica 100 million years ago and continues to move northwards at 7 centimetres per year. The current ice age started when South America separated from Antarctica some 34 million years ago. Plate tectonics isolated Antarctica after South America had moved northwards and the Drake Passage formed. Circum-polar currents formed and prevented warm, southward-moving water from reaching Antarctica. As a result, the Antarctic ice sheets formed.
Arctic ice formed 2.5 million years ago when plate tectonic-driven volcanoes in central America joined North America to South America and stopped Pacific and Atlantic Ocean waters from mixing. This was exacerbated by a supernova explosion that bombarded Earth with cosmic particles to produce cloudiness and cooling.
The Earth has been slowly cooling for the last 50 million years from times when life thrived and rapidly diversified. In these warmer times, there were no mass extinctions due to natural warming and, if the planet is warming today, the past shows us that life will thrive and diversify even more.
Once the Antarctic ice formed, ice sheets waxed and waned depending on whether Earth was closer or more distant from the Sun. Within these cycles there were smaller cycles driven by variations in energy emitted from the Sun producing many short warm spikes during long glaciations and very short cold spikes during short interglacials with average temperature rises and falls of more than 10°C a decade.
On a scale of tens of millions of years or more, the Earth’s climate is driven by plate tectonics. On a scale of hundreds of thousands of years, the Earth’s climate is driven by orbital cycles which bring Earth closer to or more distant from the Sun. On a scale of thousands of years to decades, the Earth’s climate is driven by variations in energy emitted from the Sun.
If governments, the UN or climate activists want to stop the normal planetary process of climate change, then they need to stop plate tectonics, stop variations in the Earth’s orbit and stop variations in solar output. Even the omnipotent, omnipresent Kevin Rudd couldn’t manage this!
No past warming events have been driven by an increase in carbon dioxide in the atmosphere. No past cooling events were driven by a decrease in atmospheric carbon dioxide. Six of the six most recent ice ages were initiated when the Earth’s atmospheric carbon dioxide was far higher than at present. Atmospheric temperature rise occurs before the carbon dioxide content of the atmosphere rises. It has never been proven that human emissions of carbon dioxide drive global warming despite numerous requests to climate activist scientists for the published evidence. Trillion-dollar bankrupting decisions on energy policy are being made using invalid science.
The peak of the last orbitally-driven interglacial was 7,000 to 4,000 years ago and for the last 4,000 years the Earth has been cooling as the climate changes from an interglacial into glaciation. There were solar-driven warm spikes such as the Minoan Warming, Roman Warming, Medieval Warming and the Modern Warming and cold spikes (e.g. Dark Ages, Little Ice Age) during this 4,000-year cooling trend.
In 2020, we entered the Grand Solar Minimum which is calculated to end in 2053. Whether there will be a solar-driven cooling, similar to the Little Ice Age (1300-1850 AD), or a full-blown orbitally-driven glaciation, such as the last glaciation from 116,000-14,400 years ago, is unknown. The former cooling could last for hundreds of years whereas the latter would last for at least 90,000 years. If there was another period of sustained subaerial volcanism, cooling would be accelerated.
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