Friday physics fun: today is Midsummer Eve in Sweden. Midsummer proper is the summer solstice, when the Earth's axis is tilted most towards the sun in the northern hemisphere and the days up here are longest.
Earth's orbit is elliptic so there is also a perihelion day when it is closest to the sun: Jan 5 this year. Aphelion (largest distance) on July 4th. Dates vary a bit because of the moon: both are moving around their centre of mass (which is what is really orbiting elliptically).
Because of aphelion we only get ~93.55% of the perihelion sunlight right now. This is not much of a difference compared to the big difference due to the seasons, but makes the northern hemisphere summers a bit cooler and winters a bit warmer.
Since the axis of rotation precesses in a circle with a period of 25,772 years in 13,000 years the situation will be the opposite: slightly hotter summers and colder winters. The orbit is also precessing, with a period of 112,000 years. https://en.wikipedia.org/wiki/Apsidal_precession
These factors (plus a few more like orbit eccentricity, axis obliquity, orbit inclination) drive long-term climate cyclicity: "Milankovitch cycles". https://en.wikipedia.org/wiki/Milankovitch_cycles
These are inputs: there are also lots of feedbacks in atmosphere, biosphere, cryosphere and geosphere.
Summer will get warmer after midsummer, since heat is accumulating in bodies of water and other thermal reservoirs. There is a lag, which is why winter also lingers long after the Midwinter solstice (also known as Christmas).
The thermal inertia is much bigger for planets with oceans than with ice or rock surfaces, strongly evening out temperatures. https://arxiv.org/abs/1205.5034  Ocean worlds, as long as they don't get too much greenhouse effect, can likely handle wilder orbits or tilts better.
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