Could the climate cycle be related to precession of the equinox?
Not much from the 27 thousand year precession of our poles, as that is just related to tilt of the earth, not the total incidence of radiation upon the surface as a whole.
On a planetary basis, the 100,000 year precession of earth's orbit appears to have a much greater impact for some reason.
That orbital precession moves the plane of earths orbit in and out of the mean plane of the solar system where the major debris and dust the earth can intercept, as it moves about the sun, is located. The major glacial cycle appears to most correlated with that one. One hypothesis is that metoric dust intercepting the high layers of the atmosphere provides seeding for high altitude cloud formation which reflects solar energy away from the surface of the earth while Earth passes through the main solar plane.
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Ice Ages & Astronomical Causes Origin of the 100 kyr Glacial Cycle
Figure 1-1 Global warming
Figure 1-2 Climate of the last 2400 years Figure 1-3 Climate of the last 12,000 years
Figure 1-4 Climate of the last 100,000 years
Figure 1-5 Climate for the last 420 kyr, from Vostok ice |
http://newton.ex.ac.uk/aip/physnews.252.html#1
INTERPLANETARY DUST PARTICLES (IDPs) are deposited on the Earth at the rate of about 10,000 tons per year. Does this have any effect on climate? Scientists at Caltech have found that ancient samples of helium-3 (coming mostly from IDPs) in oceanic sediments exhibit a 100,000-year periodicity. The researchers assert that their data, taken along the Mid-Atlantic Ridge, support a recently enunciated idea that Earth's orbital inclination varies with a 100-kyr period; this notion in turn had been broached as an explanation for a similar periodicity in the succession of ice ages. (K.A. Farley and D.B. Patterson, Nature, 7 December 1995.)
Farley & Patterson 1998, http://www.elsevier.com/gej-ng/10/20/36/33/37/32/abstract.html
Farley http://www.gps.caltech.edu/~farley/
Farley http://www.elsevier.nl/gej-ng/10/18/23/54/21/49/abstract.html
http://www.publicaffairs.noaa.gov/pr96/dec96/noaa96-78.html
ABRUPT CLIMATE CHANGE DURING LAST GLACIAL PERIOD COULD BE TIED TO DUST-INDUCED REGIONAL WARMING
Preliminary new evidence suggests that periodic increases in atmospheric dust concentrations during the glacial periods of the last 100,000 years may have resulted in significant regional warming, and that this warming may have triggered the abrupt climatic changes observed in paleoclimate records, according to a scientist at the Commerce Department's National Oceanic and Atmospheric Administration. Current scientific thinking is that the dust concentrations contributed to global cooling.
Possibly, but Venus, Mars, Pluto, and Triton (that we know of) are also showing warming. That makes me think it is something common to the whole solar system, like the sun perhaps.
Very possibly. Little in known about the century and millenial variation in solar activity. However what is known is that solar activity has definitely risen since the Maunder Minimums of the little ice age of the lows in the first temperature graphic above.
"Carbon dioxide, the main culprit in the alleged greenhouse-gas warming, is not a "driver" of climate change at all. Indeed, in earlier research Jan Veizer, of the University of Ottawa and one of the co-authors of the GSA Today article, established that rather than forcing climate change, CO2 levels actually lag behind climatic temperatures, suggesting that global warming may cause carbon dioxide rather than the other way around."
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"Veizer and Shaviv's greatest contribution is their time scale. They have examined the relationship of cosmic rays, solar activity and CO2, and climate change going back through thousands of major and minor coolings and warmings. They found a strong -- very strong -- correlation between cosmic rays, solar activity and climate change, but almost none between carbon dioxide and global temperature increases."