Carbon Dioxide and Earth's Future Pursuing the ... - Magazooms

1. Unprecedented Warming of the Planet
www.co2science.org
P a g e | 6
The claim: With respect to air temperature, the climate-alarmist contention is multifaceted. It is
claimed that over the past several decades: (a) earth’s temperature has risen to a level that is
unprecedented over the past millennium or more, (b) the world has been warming at a rate that
is equally unprecedented, and (c) both of these dubious achievements have been made possible
by the similarly unprecedented magnitude of anthropogenic CO2 emissions, due to humanity’s
ever-increasing burning of fossil fuels such as coal, gas and oil.
With respect to the level of warmth the earth has recently attained, it is important to see how
it compares with prior temperatures experienced by the planet, in order to determine the
degree of "unprecedentedness" of its current warmth.
Taking a rather lengthy view of the subject, Petit et al. (1999) found that peak temperatures
experienced during the current interglacial, or Holocene, have been the coldest of the last five
interglacials, with the four interglacials that preceded the Holocene being, on average, more
than 2°C warmer (see figure at right). And in a more recent analysis of the subject, Sime et al.
(2009) suggested that the “maximum
interglacial temperatures over the
past 340,000 years were between
6.0°C and 10.0°C above present-day
values.” If anything, therefore, these
findings suggest that temperatures of
the Holocene, or current interglacial,
were indeed unusual, but not
unusually warm. Quite to the
contrary, they have been unusually
cool.
But could the higher temperatures of
the past four interglacials have been
caused by higher CO2 concentrations
due to some non-human influence?
Absolutely not, for atmospheric CO2
concentrations during all four prior
Proxy temperature anomalies derived by Petit et al.
(1999) from the Vostok ice core in Antarctica..
interglacials never rose above approximately 290 ppm; whereas the air’s CO2 concentration
today stands at nearly 390 ppm.
Combining these two observations, we have a situation where, compared with the mean
conditions of the preceding four interglacials, there is currently 100 ppm more CO2 in the air
than there was then, and it is currently more than 2°C colder than it was then, which adds up to
one huge discrepancy for the world’s climate alarmists and their claim that high atmospheric
CO2 concentrations lead to high temperatures. The situation is unprecedented, all right, but
not in the way the public is being led to believe.
[ search engine powered by magazooms.com ]