Starship Asterisk*

ta152h0 wrote:here at 48 deg North, the further away the sun is, the hotter it gets , at 122 deg West

Ann wrote: may protect us northerners from some unpleasant weather records.
Ann

De58te wrote:
I am not sure about the unpleasant records. If the position of the sun is based on the elliptical orbit, then the precession of the equinoxes means that some 13,000 years ago the Sun was farthest away in the Northern Hemisphere in the winter. 13,000 years ago was when the last Ice Age began melting up and warming. 26,000 years ago when the situation was the same as today, the Northern Hemisphere was in the midst of the Ice Age. 39,000 years ago when the Sun was the farthest away again in the North, is when the Ice Age began. My guess is that the Sun isn't the main cause of climate change, but it could also be influenced by volcanoes, continental drift, ocean currents, and yes, man made climate change.

https://en.wikipedia.org/wiki/Milankovitch_cycles wrote:
<<Milankovitch cycles describe the collective effects of changes in the Earth's movements on its climate over thousands of years. The term is named after Serbian geophysicist and astronomer Milutin Milanković. In the 1920s, he theorized that variations in eccentricity, axial tilt, and precession of the Earth's orbit resulted in cyclical variation in the solar radiation reaching the Earth, and that this orbital forcing strongly influenced climatic patterns on Earth.

The angle of the Earth's axial tilt with respect to the orbital plane (the obliquity of the ecliptic) varies between 22.1° and 24.5°, over a cycle of about 41,000 years. The current tilt is 23.44°, roughly halfway between its extreme values. The tilt last reached its maximum in 8,700 BCE. It is now in the decreasing phase of its cycle, and will reach its minimum around the year 11,800 CE. Increased tilt increases the total annual solar radiation at higher latitudes, and decreases the total closer to the equator. The current trend of decreasing tilt, by itself, will promote milder seasons (warmer winters and colder summers), as well as an overall cooling trend. Because most of the planet's snow and ice lies at high latitude, decreasing tilt may encourage the onset of an ice age for two reasons: There is less overall summer insolation, and also less insolation at higher latitudes, which melts less of the previous winter's snow and ice.

The Earth's orbit approximates an ellipse. Eccentricity measures the departure of this ellipse from circularity. The shape of the Earth's orbit varies between nearly circular (with the lowest eccentricity of 0.000055) and mildly elliptical (highest eccentricity of 0.0679) Its geometric or logarithmic mean is 0.0019. The major component of these variations occurs with a period of 413,000 years (eccentricity variation of ±0.012). Other components have 95,000-year and 125,000-year cycles. They loosely combine into a 100,000-year cycle (variation of −0.03 to +0.02). The present eccentricity is 0.017 and decreasing..

Of all the orbital cycles, Milankovitch believed that obliquity had the greatest effect on climate, and that it did so by varying the summer insolation in northern high latitudes. Therefore, he deduced a 41,000-year period for ice ages. However, subsequent research has shown that ice age cycles of the Quaternary glaciation over the last million years have been at a 100,000-year period, which matches the eccentricity cycle.

Various explanations for this discrepancy have been proposed, including frequency modulation or various feedbacks (from carbon dioxide, cosmic rays, or from ice sheet dynamics). Some models can reproduce the 100,000-year cycles as a result of non-linear interactions between small changes in the Earth's orbit and internal oscillations of the climate system.

Jung-Eun Lee of Brown University proposes that precession changes the amount of energy that Earth absorbs, because the southern hemisphere's greater ability to grow sea ice reflects more energy away from Earth. Moreover, Lee says, "Precession only matters when eccentricity is large. That's why we see a stronger 100,000-year pace than a 21,000-year pace."

Some have argued that the length of the climate record is insufficient to establish a statistically significant relationship between climate and eccentricity variations.>>

bill ritchie wrote: ↑Mon Nov 01, 2021 10:07 pm "So the most distant sunrise occurs during northern summer, when the planet's north pole is tilted toward the Sun and the north enjoys longer, warmer days."

Conversely, the Sun is closest in the Southern Hemisphere Summer. That is why New Zealand, Australian, South African and South American wines, cultivar for cultivar and latitude for latitude, taste better imho.
Bill Ritchie.

Chris Peterson wrote: ↑Tue Nov 02, 2021 1:43 pm

bill ritchie wrote: ↑Mon Nov 01, 2021 10:07 pm
"So the most distant sunrise occurs during northern summer, when the planet's north pole is tilted toward the Sun and the north enjoys longer, warmer days." Conversely, the Sun is closest in the Southern Hemisphere Summer. That is why New Zealand, Australian, South African and South American wines, cultivar for cultivar and latitude for latitude, taste better imho.

Maybe. But the effect of perihelion on the northern winter is significantly greater than the effect of aphelion on the southern summer, because of the fact that the southern hemisphere is mostly ocean, which substantially moderates the temperature compared with the north.