3 ms·

The result of which is ... ? Does this lead to some occurrence such as a mass extinction or something of that nature? Seems interesting.

deleted 8y ago
[deleted]
Alex3917 8y ago
> Does this lead to some occurrence such as a mass extinction or something of that nature? I have no doubt there will be dozens of astrology videos about this on YouTube within a few days.
mygo 8y ago
it would be interesting to see how this correlates with known glaciation periods.
matte_black 8y ago
As the orbit elongates we experience greater variation in distance from the sun. At the extremes, we get colder winters and hotter summers. Perhaps another explanation for climate change.
- thaumasiotes 8y ago
  Why would more eccentricity lead to colder winters and hotter summers in each hemisphere? How would that work?
  - LoSboccacc 8y ago
    yeah makes little sense since the earth is closer to the sun in january. if anything higher eccentricity should reduce seasonal differences. (seasonal differences being driven mostly by earth tilt, not distance from sun)
cryptonector 8y ago
At times of higher eccentricity you get more pronounced differences between summer and winter. If this coincides with a glacial period (and it has) that probably means that the glacial period sets in faster / is colder than when the orbital eccentricity is low -- but it also means that interglacials set in faster and are warmer.
- thaumasiotes 8y ago
  > At times of higher eccentricity you get more pronounced differences between summer and winter. Why would this be the case?
  - cryptonector 8y ago
    Because eventually perigee coincides with summer or winter in either the Northern or Southern hemisphere (and then the apogee will coincide with the other hemisphere's opposite season, naturally), so one of them will get more sunlight (heat). BUT! The Northern hemisphere has much more landmass than the Southern one, which accentuates the differences between seasons because land heats up faster in the summer and cools down faster than the oceans in the winter, and also land provides a platform for ice accumulation. This is the reason that glacial periods involve much more ice in the Northern hemisphere than in the Southern hemisphere. It is generally believed that glacial periods set in when the Northern summer coincides with the furthest point from the Sun on Earth's orbit, while interglacials set in when the Northern summer coincides with the point of closest approach to the Sun. Summer is the key because once ice lasts past the summer then summer cannot heat up the Northern hemisphere as much as usual: ice reflects a lot of the Sun's energy. Conversely, if the summer is warm enough to melt more snow and ice than was accumulated during winter, then you can't have a glacial period. It is important to note that there are other orbital cycles that matter here, especially the precession of the equinoxes, which is the cycle that relates which hemisphere gets its summer closest to the Sun. Earth's axis of rotation itself rotates, very very slowly. The precession of the equinoxes is a 25ky cycle. Another cycle is the angle of the Earth's axis of rotation to the ecliptic. This varies a fair bit over the years, and this one is (IIRC) the most chaotic of the orbital cycles. All of these cycles, known as the Mylankovitch cycles[0], have winter/summer difference accentuation/attenuation effects. The Mylankovitch cycle theory is that when these coincide in certain ways you get glacial or interglacial periods. [0] https://en.wikipedia.org/wiki/Milankovitch_cycles https://en.wikipedia.org/wiki/Milankovitch_cycles

deleted 8y ago

[deleted]

Alex3917 8y ago

> Does this lead to some occurrence such as a mass extinction or something of that nature? I have no doubt there will be dozens of astrology videos about this on YouTube within a few days.

mygo 8y ago

it would be interesting to see how this correlates with known glaciation periods.

matte_black 8y ago

As the orbit elongates we experience greater variation in distance from the sun. At the extremes, we get colder winters and hotter summers. Perhaps another explanation for climate change.

thaumasiotes 8y ago
Why would more eccentricity lead to colder winters and hotter summers in each hemisphere? How would that work?
- LoSboccacc 8y ago
  yeah makes little sense since the earth is closer to the sun in january. if anything higher eccentricity should reduce seasonal differences. (seasonal differences being driven mostly by earth tilt, not distance from sun)

cryptonector 8y ago

At times of higher eccentricity you get more pronounced differences between summer and winter. If this coincides with a glacial period (and it has) that probably means that the glacial period sets in faster / is colder than when the orbital eccentricity is low -- but it also means that interglacials set in faster and are warmer.

thaumasiotes 8y ago
> At times of higher eccentricity you get more pronounced differences between summer and winter. Why would this be the case?
- cryptonector 8y ago
  Because eventually perigee coincides with summer or winter in either the Northern or Southern hemisphere (and then the apogee will coincide with the other hemisphere's opposite season, naturally), so one of them will get more sunlight (heat). BUT! The Northern hemisphere has much more landmass than the Southern one, which accentuates the differences between seasons because land heats up faster in the summer and cools down faster than the oceans in the winter, and also land provides a platform for ice accumulation. This is the reason that glacial periods involve much more ice in the Northern hemisphere than in the Southern hemisphere. It is generally believed that glacial periods set in when the Northern summer coincides with the furthest point from the Sun on Earth's orbit, while interglacials set in when the Northern summer coincides with the point of closest approach to the Sun. Summer is the key because once ice lasts past the summer then summer cannot heat up the Northern hemisphere as much as usual: ice reflects a lot of the Sun's energy. Conversely, if the summer is warm enough to melt more snow and ice than was accumulated during winter, then you can't have a glacial period. It is important to note that there are other orbital cycles that matter here, especially the precession of the equinoxes, which is the cycle that relates which hemisphere gets its summer closest to the Sun. Earth's axis of rotation itself rotates, very very slowly. The precession of the equinoxes is a 25ky cycle. Another cycle is the angle of the Earth's axis of rotation to the ecliptic. This varies a fair bit over the years, and this one is (IIRC) the most chaotic of the orbital cycles. All of these cycles, known as the Mylankovitch cycles[0], have winter/summer difference accentuation/attenuation effects. The Mylankovitch cycle theory is that when these coincide in certain ways you get glacial or interglacial periods. [0] https://en.wikipedia.org/wiki/Milankovitch_cycles https://en.wikipedia.org/wiki/Milankovitch_cycles