First 332 words of the document:
Earth's orbit Diagram Cycle Description
Stretch / 96,000 The path of the Earth's orbit around the sun changes from an almost perfect circle to an ellipse
Eccentricity years and back again about every 96,000 years.
This changes the distance from the Sun to the earth, and so the amount of energy the Earth
receives from the sun (at different times of the year)
Earth's orbit is elliptical right now it's closest to the sun in January and furthest in July
Tilt / 41,000 The Earth is tilted at an angle as it orbits the sun, called its axis (currently 23.5°)
This changes between about 21.8° and 24.4° over a cycle of about 41,000 years.
The changes in tilt change the amount of energy that different latitudes receive, changing global
When the tilt is greater (24.4°), areas that receive lots of energy, such as the tropics, will be
larger. Other climate regions, such as the temperate zones beyond the tropics, will be smaller.
Wobble / 22,000 The axis of the Earth also wobbles like a spinning top on a cycle of about 22,000 years.
Because Earth is closest to the sun in January, winter in the northern hemisphere is mild and
summer is cool.
The wobble of the axis means this gradually changes the seasons will eventually swap
When this happens, the Earth will still be closest to the sun in January, but this will now be
summer in the northern hemisphere. The Earth will still be furthest away from the sun in July, but
this will now be winter in the northern hemisphere.
So in the northern hemisphere, winter would then be colder because it would be at the time
when the Earth is further away from the sun, and summer would be hotter, because it's at the
time when the Earth is closer to the sun