It is not human interference. . .

Thus, over the past half-million years and within
the context of the most recent five full interglacials, it
is clear the average near-surface air temperature of
Earth during the 1990s was not unusually warm, but
unusually cool, despite the 1990s’ much greater
atmospheric CO2 content.
These observations suggest Earth’s current
temperature is not indicative of dangerous human
interference with the planet’s thermoregulatory
system. The IPCC’s claim of a human influence on
today’s climate is based solely on its contention that
Earth’s current temperature is uncommonly high
(Crowley, 2000), when it clearly is not. Earth was
significantly warmer than it is today in all of the
preceding interglacials for which we have good
temperature data,

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