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The Younger Dryas period was about twelve thousand years ago, and the periods in between cooling cycles are around 23,000 years long (also called the Precession of the Equinoxes^)
In astronomy, axial precession is a gravity-induced, slow, and continuous change in the orientation of an astronomical body's rotational axis. In particular, it can refer to the gradual shift in the orientation of Earth's axis of rotation in a cycle of approximately 25,772 years. Earth's precession was historically called the precession of the equinoxes,
Ref
Since the middle Quaternary, glacial–interglacial cycles have had a frequency of about 100,000 years (Lisiecki and Raymo 2005). In the solar radiation time series, cycles of this length (known as “eccentricity”) are present but are weaker than cycles lasting about 23,000 years (which are called “precession of the equinoxes”).
The precession of the equinoxes refers to the observable phenomena of the rotation of the heavens, a cycle which spans a period of (approximately) 25,920 years, over which time the constellations appear to slowly rotate around the earth, taking turns at rising behind the rising sun on the vernal equinox.
The difference of +-1.5 thousand years when talking that time range, and when by definition the time range is approximate, I fail to see what your point is, as it is insignificant.
Now please- do you have anything to add to the discussion I'm proposing?
Or do you want to talk about word choice when referencing some extremely small detail of one of my links?
how so?
Though they are consistent with the Milankovitch hypothesis, there are still several observations that the hypothesis does not explain.
The article discusses the effects of man-made increases in CO2 levels, then explains the expected warming effects from that, followed by return of glaciation.
Will the greenhouse effect prevent the return of glaciers?
I don't know if man can "fend off the cold when the ice age comes". New York City was under a mile thick ice sheet during the last glacier so it's not a matter of turning up the heater in your apartment, and the world can't feed 9 billion people if much of our current farmland becomes glaciers.
average temperatures might well rise by about 5 degrees C–with devastating effects for us earthlings, such as rising sea levels and dramatic changes in weather patterns.
But even that warming will not stave off the eventual return of huge glaciers, because ice ages last for millennia and fossil fuels will not.In about 300 years, all available fossil fuels may well have been consumed.Over the following centuries, excess carbon dioxide will naturally dissolve into the oceans or get trapped by the formation of carbonate minerals. Such processes won’t be offset by the industrial emissions we see today, and atmospheric carbon dioxide will slowly decline toward preindustrial levels. In about 2,000 years, when the types of planetary motions that can induce polar cooling start to coincide again, the current warming trend will be a distant memory.
This means that humanity will be hit by a one-two punch the likes of which we have never seen. Nature is as unforgiving to men as it was to dinosaurs; advanced civilization will not survive unless we develop energy sources that curb the carbon emissions heating the planet today and help us fend off the cold when the ice age comes.
A new study by the Woods Hole Oceanographic Institution (WHOI) clarifies what influence major currents in the North Atlantic have on sea level along the northeastern United States. The study, published June 13 in the journal Geophysical Research Letters, examined both the strength of the Atlantic Meridional Overturning Circulation (AMOC)—a conveyor belt of currents that move warmer waters north and cooler waters south in the Atlantic—and historical records of sea level in coastal New England.
Nick Balascio explained that the Gulf Stream/Deep Water system is known as the AMOC, or Atlantic Meridional Overturning Circulation. Balascio, an assistant professor in William & Mary's Department of Geology, is a member of a group of scientists that found evidence that changes in the strength of AMOC can serve as an precursor to massive future climate changes.
Their findings were published in the journal Nature Communications in a paper "Deep-water circulation changes lead North Atlantic climate during deglaciation." Deglaciation, or the widespread melting of glaciers, have triggered massive shifts in climate. Balascio explains that the team's evidence shows that a strengthening in the AMOC flow was a precursor to a sudden warming trend about 11,000 years ago.
Conversely, a weakening AMOC was followed by what is known as the Younger Dryas stadial, a major cooling period about 13,000 years ago. Balascio pointed out that each shift in AMOC strength preceded the climactic shift by the same amount of time—around 400 years.