What Really Causes Climate Change? By Laurence Hecht

14th March 2007

Dynamics of Earth-Sun orbital relationships, and not statisti- we have just presented. He might also argue that the recent

cal trends in greenhouse gases, are the principal cause of cli- decades’ warming trend—that is an upward trend of about

mate change, as the past 2-million-year record of Ice Ages one-half degree celsius in the global averaged temperature,

demonstrates. Although these facts are known to every com- most of it over the oceans at night—“proves” his case.

petently trained climate scientist, they do not seem ever to How does the informed citizen decide? Is he forced to

have penetrated the cranium of Al Gore. Consider first these choose between competing trend lines, as in a typical modern

items: investment prospectus, hoping that what is going up now will

continue to rise, or what is falling, fall?

• Early in February, storms dumped more than 12 feet Fortunately, there is a science of climate which can tell us

of snow on upstate Redfield, N.Y., breaking the state some things about our past, and also some things, though not

record of 10 feet 7 inches made just five years earlier. all we would wish to know, about our future prospects. By

• Jan. 3, 2007, a record snowfall buried Anchorage, the word science, we mean here a rational and rigorously

Alaska, accumulating 57.60 inches. established conception of cause. This, as opposed to the cur-

• Jan. 17, 2006 a record snowfall blanketed northwest rent fad of extrapolation from statistical trend lines, a fad

Japan, dropping more than 3 meters of snow on some which has become as wildly popular in the global warming

areas. More than 80 people died. The snow started as in the hedge funds industry. (Indeed, present trends cannot

coming down in December, which was the coldest predict which of these two sources of high-paid employment

December for many areas since 1946. for the statistically inclined shall disappear first.)

• March 2, 2005, temperatures fell to a 100-year low

in Germany. The Swiss capital of Bern registered We Are in an Ice Age

minus 15.6 degrees celsius, its coldest for the season Just 12,000 years ago, the North American continent was

since data began to be collected in 1901. France beat covered by a sheet of ice, from 1 to 2 miles thick, reaching

records set in 1971. down to New York City, and spreading across Pennsylvania,

• Jan. 5, 2001, National Oceanic and Atmospheric Ad- through Ohio, Indiana, Illinois, and into the prairie states.

ministration (NOAA) scientists announced that the Tongues of the glacier reached down from the Rocky Moun-

U.S. national temperature during the November tains and Appalachian heights at much more southerly locathrough

December two-month period was the coldest tions. As the glacier retreated in the period from approxisuch

period on record. Forty-three states within the mately 10,000 to 8,000 B.C. the landscape we now know

contiguous U.S. recorded below average tempera- was formed—the Great Lakes, the upper Ohio and Missouri

tures during the November-December period. Rivers, the lakes dotting the northern tier, all of which had

• Aug. 25, 1999, Mt. Baker, Washington set a record been buried under ice for 100,000 years. A similar situation

for the most snowfall ever measured in the United prevailed over northern Europe and Russia, with the differStates

in a single season (1140 inches), NOAA re- ence that the ice had retreated about 1,000 years earlier than

ported. the North American Laurentide ice sheet.1

The huge volume of water tied up in these ice sheets had

Thanks to a $6-billion a year government-funded “climate come mostly from the oceans. Sea levels during the period of

industry,” whose mission is to convince you that globalwarm- extended glaciation were 200 to 400 feet lower than today’s,

ing is here, you’ve probably forgotten many of these events. as the recent evidence of ancient cities found underwater off

Yet vivid images of lonely polar bears floating on ice, and the Indian coastline has again confirmed.

Inuits telling of warmer than usual summers, haunt your imag- We know these things from the work of geologists and

ination. Such is the power of advertising over an audience

little schooled in climate science. 1. Laurence Hecht, “The Coming (or Present) Ice Age,” 21st Century Science

No doubt, a resourceful opponent might assemble anec- & Technology, Winter 1993-1994, pp. 22-35. www.21stcenturysciencedotal

evidence of recent warm events to counter the cases tech.com/Articles%202005/ComingPresentIceAge.pdf

6 Science EIR March 2, 2007

in the amount of solar radiation reaching the Earth.

At almost the same time, a skilled mathematician from

the University of Belgrade, Milutin Milankovitch (1879-

1958), had independently begun his own investigation of the

astronomical theory of climate. In 1920, after nine years of

work, Milankovitch published a book in the French language,

The Mathematical Theory of Heat Phenomena Produced by

Solar Radiation. Therein he identified the three major cyclical

variables which, some 50 years later, became indisputably

recognized as the principal cause of climate change. When

Ko¨ppen read the book, he sent a postcard to Milankovitch,and a collaboration developed among the two, and Ko¨ppen’s

son-in-law, the astronomer-geologist and daring polar explorer,

Alfred Wegener.

The essential point of their work was this: The amount of

solar radiation (insolation) reaching the Earth, depends upon

the distance of the Earth from the Sun and on the angle of

incidence of the Sun’s rays upon the Earth’s surface. These

angles and distances vary over long cycles of tens of thousands

of years.

Anastasia Sotiropoulos, based on CLIMAP For a glacier to grow, it is only necessary that the amount

The Northern Hemisphere at the time of the last glacial climax,

about 18,000 years ago.

of snow and ice accumulated over the Winter season not be

melted back by the Sun’s rays during the warmer months. In

the short, cool summers of the high polar latitudes, there may

other specialists over the past two centuries. Most of what or may not be enough solar radiation to melt back the winter’s

we report here was known by the early decades of the 20th accumulation. The small changes in insolation, produced by

Century. Correlation and cross-checking of evidence from the changing orbital relationships, it was thought, might be

North America and Eurasia first showed the simultaneous just enough to change the delicate balance of glacial stability

existence of these huge ice sheets. But soon, new evidence to one of advance. Once the advance starts, the increased

established that there had been not one, but several periods of reflectivity of the ice surface, as compared to sea or land

Northern Hemisphere glaciation. cover, cools the local atmosphere further and causes a self-

Today we know that in the last 800,000 years, eight suc- feeding process of glacial growth and spread. This might excessive

periods of glaciation, each lasting approximately plain the cycles of the Ice Ages.

100,000 years, have occurred. Between many of these glacia- To give an example: As every schoolchild learns, the

tions there occurred a warming period, known as an intergla- yearly variation of the seasons is not caused by the change in

cial and lasting approximately 10,000 to 12,000 years, during the Earth’s distance from the Sun, but by the inclination ofwhich the ice retreated back to its resting place in Greenland the Earth’s axis, which causes the Sun’s rays to strike the

and the polar regions. All the while, the continent of Antarc- Earth at an oblique angle, in a manner that varies as the Earth

tica remained covered in ice, as it still does today, holding makes its annual path of revolution about the Sun. Were there

now about 90% of the world’s ice at an average thickness of no axial inclination, there would be no difference of seasons

one and-a-quarter miles. and a much slighter variation in temperature from the Equator

to the high latitudes. But the Earth’s axial tilt, known techniTheAstronomical Determination cally as the obliquity of the ecliptic, changes on a 40,000-year

What was causing the periodic advance and retreat of the cycle from 22 to 24.5 degrees. The more inclined the Earth

glaciers? In 1910, Vladimir Ko¨ppen (1846-1940), a Russian- is, the more extreme are the variations between Summer and

German meteorologist trained in planetary astronomy and Winter, particularly in the high northern latitudes where the

very much acquainted with the work of Kepler, had been cycle of glaciation is to be triggered.

musing over the work of two Alpine glaciologists. In their Apart from obliquity, two other astronomical cycles

extensive field studies, Albrecht Penck and Eduard Bru¨ckner which affect insolation were known:

had identified four separate cycles of glacial advance and • the 26,000-year period of the precession of the equinox,retreat in the Alps. To try to make sense of their work,Ko

¨ppen which, when combined with the advance of the periheliontook up a hyothesis that had been first proposed in 1830 by (the point at which the Earth is closest in its orbit to the Sun)

Sir John Herschel, that long-term cyclical variations in the produces a 21,000-year cycle;

Earth’s orbital relationship to the Sun would produce changes • the 90,000 to 100,000-year cycle of variation of the

EIR March 2, 2007 Science 7


Milankovitch’s Radiation Curve for the Last 190,000 Years

This curve of the fluctuation in intensity of solar radiation over time, depending on the orbital parameters, was reproduced by Ko¨ppen and

Wegener in their pioneering work, Die Klimate der geologischen Vorzeit (The Climates of the Geological Past), published in 1924.

eccentricity of the Earth’s elliptical orbit. young researchers at Columbia University’s Lamont-Doherty

At the encouragement of Ko¨ppen, Milankovitch calcu- Geological Laboratory.2 There, Hays, Imbrie, and Shackletonlated the effect of the three astronomical cycles on Northern described the orbital variations as

“pacemakers of the IceHemisphere glaciation for 650,000 years into the past and Ages.” The 100,000-year cycle was found to be the strongest,

160,000 years into the future. This came to be known as the a fact which correlated with other evidence suggesting that

Milankovitch-cycle theory of climatic history. Although Mi- the Northern Hemisphere ice sheets had advanced and relankovitch

was still fighting an uphill battle at the time of his treated on a 100,000-year cycle. Within that long cycle, the

death in 1958, within two decades his general theory had evidence showed a 20,000-year cycle of temperature change,

become widely accepted. which was not sufficient to cause full glacial retreat. However

when the two cycles compounded, sometimes amplified by

Pacemaker of the Ice Ages low points in the 40,000-year cycle of obliquity, an intergla-Much of the corroborating evidence came from the field cial would occur. The ice sheet would melt back and retreat up

of paleobiology. An innovative technique of estimating the to Greenland and far northerly locations. It would be reversed

sea level temperature came from the field of nuclear isotope when the 20,000-year cycle of precession of the equinox

science. Since the 19th Century, biologists had observed reached its maximum, and a new glaciation would initiate.

small sea creatures known as foraminifera, which thrive near The astounding thing about this confirmation of the

the ocean surface, form calcareous shells, and die, depositing Koppen-Wegener-Milankovitch hypothesis, is that it inditheir

fossil shells on the ocean bed in layers known as the cates that we are set for a new advance of the ice sheet.Weare

Globigerina ooze. The ratio of two stable isotopes of oxygen, now about 11,000 to 12,000 years into the recent interglacial.

oxygen-16 and oxygen-18, is very sensitive to the tempera- Obliquity is relatively high at 23.5 degrees, and the Northern

ture of the sea water in which it is dissolved. The temperature Hemisphere Summer is occurring near the point of aphelion,

of sea water at a given time could thus be inferred from the precisely the conditions of reduction in insolation which

relative proportion of these two oxygen isotopes found in the would tend to produce the onset of a glacial event. The only

carbonate shells of these fossilized sea creatures. Analysis, moderating factor among the astronomical determinants is

by these and other means, of deep-sea core samples taken in the eccentricity, which is relatively low. Were the orbital perthe

1970s showed the Milankovitch periodicities of 20,000,

40,000, and 100,000 years, going back for 1.7 million years. 2. J.D. Hays, J. Imbrie, and N.J. Shackelton, 1976. “Variations in the Earth’s

The results were written up in a famous paper by three Orbit: Pacemaker of the Ice Ages,” Science, Vol. 194, pp. 1121-32.

8 Science EIR March 2, 2007


Obliquity and Intensity of the Sun’s Rays Precession and Location of the Solstice

The precession cycle changes the location on the ellipse where the

Winter and Summer solstices occur. The Summer solstice now

occurs near aphelion, the point at which the Earth is most distant

from the Sun.

term, cyclical variations in the Sun’s output, which may actas an amplifier of other cycles.3 The most popular theory today

proposes that shifts in the thermohaline circulation, the global

ocean current which circulates cold water from the north AtEven

without a tilt of the axis, the variation in angle of incidence of lantic around the cape of Africa to the northeastern Pacific,

the Sun’s rays (a) would cause the poles to be cooler. Increasing may be the trigger for the sudden changes which bring on the

the angle of obliquity amplifies the effect (b). Ice Ages.

Of all the hypotheses, that of human-produced carbon

dioxide as the forcing mechanism for warming is the most

turbations the sole cause of the glacial cycle, we should be deeply and extensively studied, and by far the most discredseeingan ice sheet begin to creep across our high northern ited. No other hypothesis rests on such flagrant and lying

latitudes even now. Perhaps we shall. disrespect for data as that illustrated in our accompanying

However, as Milankovitch himself had already recog- piece on the falsification of the historical CO2 record. Dollar

nized, the variations in insolation produced by the orbital for dollar, the American taxpayer has never gotten so little

changes are not enough, in themselves, to drive the enormous and spent so much as on the government’s promotion of the

shift in climate which a glacial onset represents. The orbital hoax known as global warming. NASA Administrator Mike

variations must rather be a pacemaker, a pre-amplifier per- Griffin had the courage to say it. In an interview with thehaps, which drives, or signals, other events still not known. German daily

Frankfurter Allgemeine Zeitung Jan. 26, Griffin

Many climatologists have attempted to find those other fac- said that despite an annual investment of $5.5 billion in retors,and a large and interesting literature on the subject exists, search on planet Earth,

“we have yet to find out whether the

much of it compiled by the late Columbia University Profes- present climate change is man-made, or just a short-term vacsor

Rhodes Fairbridge when he edited the Encyclopedia of illation.”

Earth Sciences. The finely tailored suit of global warming has been woven

Attempts include such far-reaching, yet plausible causes with an invisible silk thread. It is time that Congress and the

as changes in the Saturn-Jupiter alignment affecting tectonic American people face up to it, lest they find themselves bothshifts in the Earth’s mantle, the effect of variations in the solar naked and freezing.

wind on weather systems by mediation of changes in cosmic

radiation, volcanic activity, and shifts in Earth’s magnetic

cycles. A large literature also exists on the effect of shorter- 3. For example, the work of Theodore Landscheidt.

EIR March 2, 2007 Science 9

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