{"id":239643,"date":"2023-01-14T19:25:09","date_gmt":"2023-01-14T18:25:09","guid":{"rendered":"https:\/\/climatescience.press\/?p=239643"},"modified":"2023-01-14T19:25:10","modified_gmt":"2023-01-14T18:25:10","slug":"ian-plimer-asks-what-climate-crisis","status":"publish","type":"post","link":"https:\/\/climatescience.press\/?p=239643","title":{"rendered":"Ian Plimer Asks, \u201eWhat Climate Crisis?\u201c"},"content":{"rendered":"\n
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From Science Matters<\/a><\/p>\n\n\n\n

By\u00a0Ron Clutz<\/a><\/p>\n\n\n\n

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The supercontinent Gondwana hundreds of million years ago at its primary stages, and the directions pieces drifted away<\/p>\n\n\n\n

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That question is the title of Ian Plimer\u2019s Spectator Australia article What Climate Crisis?<\/strong> <\/a>Excerpts in italics with my bolds and added images.<\/p>\n\n\n\n

For more than 80 per cent of time, Earth has been a warm wet greenhouse planet with no ice.<\/strong> We live in unusual times, when ice occurs on continents.<\/strong> This did not happen overnight. The great southern continent, Gondwanaland, formed about 550 million years ago<\/strong>. It occupied 20 per cent of the area of our planet<\/strong> and included Antarctica, South America, Australia, South Africa and the Indian subcontinent.<\/em><\/p>\n\n\n\n

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.<\/mark><\/strong><\/em><\/p>\n\n\n\n

If Antarctica is to lose its ice sheets<\/strong> to end the current ice age, plate tectonics must move the continent northwards or fragment Antarctica<\/strong> 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<\/strong>. Plate tectonics must also widen the Bering Strait to allow more warm Pacific Ocean water<\/strong> to enter and warm the Arctic.<\/em><\/p>\n\n\n\n

Arctic ice formed 2.5 million years ago<\/strong>\u00a0when 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.<\/em><\/p>\n\n\n\n

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Figure 16. The geological history of CO2 level and temperature proxy for the past 400 million years. CO2 levels now are ~ 400ppm. Source: Davis, W. J. (2017).<\/em><\/p>\n\n\n\n

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The Earth has been slowly cooling for the last 50 million years<\/strong>\u00a0from times when life thrived and rapidly diversified. In these warmer times, there were no mass extinctions due to natural warming and,\u00a0if the planet is warming today, the past shows us that life will thrive and diversify even more.<\/strong><\/em><\/p>\n\n\n\n

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Once the Antarctic ice formed, ice sheets waxed and waned depending on whether Earth was closer or more distant from the Sun.<\/strong> Within these cycles there were smaller cycles driven by variations in energy emitted from the Sun<\/strong> 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\u00b0C a decade.<\/em><\/p>\n\n\n\n