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http://english.pravda.ru/science/earth/106922-earth_ice_age-0

Earth on the Brink of an Ice Age

The earth is now on the brink of entering another Ice Age, according to a large
and compelling body of evidence from within the field of climate science. Many
sources of data which provide our knowledge base of long-term climate change
indicate that the warm, twelve thousand year-long Holocene period will rather
soon be coming to an end, and then the earth will return to Ice Age conditions
for the next 100,000 years.

Ice cores, ocean sediment cores, the geologic record, and studies of ancient
plant and animal populations all demonstrate a regular cyclic pattern of Ice
Age glacial maximums which each last about 100,000 years, separated by
intervening warm interglacials, each lasting about 12,000 years.

Most of the long-term climate data collected from various sources also shows a
strong correlation with the three astronomical cycles which are together known
as the Milankovich cycles. The three Milankovich cycles include the tilt of the
earth, which varies over a 41,000 year period; the shape of the earths orbit,
which changes over a period of 100,000 years; and the Precession of the
Equinoxes, also known as the earths wobble, which gradually rotates the
direction of the earths axis over a period of 26,000 years. According to the
Milankovich theory of Ice Age causation, these three astronomical cycles, each
of which effects the amount of solar radiation which reaches the earth, act
together to produce the cycle of cold Ice Age maximums and warm interglacials.

Elements of the astronomical theory of Ice Age causation were first presented
by the French mathematician Joseph Adhemar in 1842, it was developed further by
the English prodigy Joseph Croll in 1875, and the theory was established in its
present form by the Serbian mathematician Milutin Milankovich in the 1920s and
30s. In 1976 the prestigious journal Science published a landmark paper by John
Imbrie, James Hays, and Nicholas Shackleton entitled Variations in the Earth's
orbit: Pacemaker of the Ice Ages, which described the correlation which the
trio of scientist/authors had found between the climate data obtained from
ocean sediment cores and the patterns of the astronomical Milankovich cycles.
Since the late 1970s, the Milankovich theory has remained the predominant
theory to account for Ice Age causation among climate scientists, and hence the
Milankovich theory is always described in textbooks of climatology and in
encyclopaedia articles about the Ice Ages.

In their 1976 paper Imbrie, Hays, and Shackleton wrote that their own climate
forecasts, which were based on sea-sediment cores and the Milankovich cycles, "
must be qualified in two ways. First, they apply only to the natural component
of future climatic trends - and not to anthropogenic effects such as those due
to the burning of fossil fuels. Second, they describe only the long-term
trends, because they are linked to orbital variations with periods of 20,000
years and longer. Climatic oscillations at higher frequencies are not
predicted... the results indicate that the long-term trend over the next 20,000
years is towards extensive Northern Hemisphere glaciation and cooler climate."

During the 1970s the famous American astronomer Carl Sagan and other scientists
began promoting the theory that greenhouse gasses such as carbon dioxide, or
CO2, produced by human industries could lead to catastrophic global warming.
Since the 1970s the theory of anthropogenic global warming (AGW) has gradually
become accepted as fact by most of the academic establishment, and their
acceptance of AGW has inspired a global movement to encourage governments to
make pivotal changes to prevent the worsening of AGW.

The central piece of evidence that is cited in support of the AGW theory is the
famous hockey stick graph which was presented by Al Gore in his 2006 film An
Inconvenient Truth. The hockey stick graph shows an acute upward spike in
global temperatures which began during the 1970s and continued through the
winter of 2006/07. However, this warming trend was interrupted when the winter
of 2007/8 delivered the deepest snow cover to the Northern Hemisphere since
1966 and the coldest temperatures since 2001. It now appears that the current
Northern Hemisphere winter of 2008/09 will probably equal or surpass the winter
of 2007/08 for both snow depth and cold temperatures.

The main flaw in the AGW theory is that its proponents focus on evidence from
only the past one thousand years at most, while ignoring the evidence from the
past million years -- evidence which is essential for a true understanding of
climatology. The data from paleoclimatology provides us with an alternative and
more credible explanation for the recent global temperature spike, based on the
natural cycle of Ice Age maximums and interglacials.

In 1999 the British journal Nature published the results of data derived from
glacial ice cores collected at the Russia s Vostok station in Antarctica during
the 1990s. The Vostok ice core data includes a record of global atmospheric
temperatures, atmospheric CO2 and other greenhouse gases, and airborne
particulates starting from 420,000 years ago and continuing through history up
to our present time.

The graph of the Vostok ice core data shows that the Ice Age maximums and the
warm interglacials occur within a regular cyclic pattern, the graph-line of
which is similar to the rhythm of a heartbeat on an electrocardiogram tracing.
The Vostok data graph also shows that changes in global CO2 levels lag behind
global temperature changes by about eight hundred years. What that indicates is
that global temperatures precede or cause global CO2 changes, and not the
reverse. In other words, increasing atmospheric CO2 is not causing global
temperature to rise; instead the natural cyclic increase in global temperature
is causing global CO2 to rise.

The reason that global CO2 levels rise and fall in response to the global
temperature is because cold water is capable of retaining more CO2 than warm
water. That is why carbonated beverages loose their carbonation, or CO2, when
stored in a warm environment. We store our carbonated soft drinks, wine, and
beer in a cool place to prevent them from loosing their fizz, which is a
feature of their carbonation, or CO2 content. The earth is currently warming as
a result of the natural Ice Age cycle, and as the oceans get warmer, they
release increasing amounts of CO2 into the atmosphere.

Because the release of CO2 by the warming oceans lags behind the changes in the
earths temperature, we should expect to see global CO2 levels continue to rise
for another eight hundred years after the end of the earths current
Interglacial warm period. We should already be eight hundred years into the
coming Ice Age before global CO2 levels begin to drop in response to the
increased chilling of the worlds oceans.

The Vostok ice core data graph reveals that global CO2 levels regularly rose
and fell in a direct response to the natural cycle of Ice Age minimums and
maximums during the past four hundred and twenty thousand years. Within that
natural cycle, about every 110,000 years global temperatures, followed by
global CO2 levels, have peaked at approximately the same levels which they are
at today.

About 325,000 years ago, at the peak of a warm interglacial, global temperature
and CO2 levels were higher than they are today. Today we are again at the peak,
and near to the end, of a warm interglacial, and the earth is now due to enter
the next Ice Age. If we are lucky, we may have a few years to prepare for it.
The Ice Age will return, as it always has, in its regular and natural cycle,
with or without any influence from the effects of AGW.

The AGW theory is based on data that is drawn from a ridiculously narrow span
of time and it demonstrates a wanton disregard for the big picture of long-term
climate change. The data from paleoclimatology, including ice cores, sea
sediments, geology, paleobotany and zoology, indicate that we are on the verge
of entering another Ice Age, and the data also shows that severe and lasting
climate change can occur within only a few years. While concern over the
dubious threat of Anthropogenic Global Warming continues to distract the
attention of people throughout the world, the very real threat of the
approaching and inevitable Ice Age, which will render large parts of the
Northern Hemisphere uninhabitable, is being foolishly ignored.

Gregory F. Fegel

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