Apart from the Sun, the PDO (Pacific decadal oscillation), ENSO (El Nino southern oscillation) and other oscillations and currents, and their synchronisation, here are a few more factors important to the climate.
Axial Tilt; (obliquity of the ecliptic) Range: from 22.1° to 24.5° (or 21° 30’ to 24° 30’) present day ~23.44° (23.439291111078° in 2000) with a major ~41,000-year period from maximum - minimum - maximum. The tilt is in its decreasing mode at present. Minimum tilt is when the oceans get the least benefit from the Sun.
Last maximum 8700 BC, mid around 1550 and the next minimum will be in 11800.
Believed to be a large factor in glaciation.
The precession of the equinoxes refers to the precession of Earth's axis of rotation with respect to inertial space.
The rotation axis of the Earth (a broomhandle shoved through the poles. Each end) describes a small circle over a period of about 25800 years, its size depending on the angle of tilt.
Currently, this annual motion is about 50.3 seconds of arc per year or 1 degree every 71.6 years. The process is slow, but cumulative. A complete precession cycle covers a period of approximately 25,765 years, the so called great Platonic year, during which time the equinox regresses over a full 360°.
There are minor variations in the tilt also known as nods that have a range of 0°0.7" to 0°8.5". They occur in a cycle of up to ~18.6 year. (See lunar orbit precession)
Eccentricity (as simple as I could make it as Wiki disappears up its maths bot)
The orbit around the Sun is not a perfect circle. It is slightly elliptical.
Seasonal variation is mainly caused by the tilt being (in human lifespan terms) permanently pointed let's call call it to the right so when we are to the right of the Sun the northern end of the broom handle is directed away from the Sun so the sunlight is spread over a greater area. When we are to the left of the Sun the tilt is directed towards it and the sunlight is more focused. When we are closest to the Sun it is winter and when we are furthest, it is summer. That we (UK wise) move closer to the Sun when Earth is to its left adds a tiny bit (~2%=~5° before moderators work their magic http://www.spenvis.oma.be/spenvis/help/background/illumination/illumination.html) to the warming effect making winter a bit less chilly and conversely when we are furthest it makes summer a bit less hot. Southern hemi temps are a bit warmer than N.hemi for the same reason but reversed.
Then we have
Polar Motion or polar wander (and you thought differential slip was difficult...)
The variation is only a few meters when considered against a static Earth, (static meaning the centre of the planet where the vertical and horizontal lines meet and the vertical goes through 0 deg latitude and 0 deg longitude, a third runs parallel to the axis and meets the other 2 where they intersect. Used for GPS)
There are 3 components:
The Chandler wobble with a period of 416 - 435 days believed driven by fluctuating pressure at the bottom of the ocean, caused by variation in ocean salinity and temperature and to a small degree by currents in and above the surface. ~20 feet.
The annual rotation of the pole
Lunar Perigee and Apogee (nearest and furthest from us)
Lunar orbit precession
Lunar orbit precession varying the maximum declination from +28°35' to +18°18' and the minimum from -18°18' to -28°35'. Currently
There are two important precessional motions in the Orbit of the Moon.
The long axis (line of the apsides: perigee and apogee) of the moon's elliptical orbit precesses about once in just under 9 years. It is caused by the solar tide. This precession period is equal to the time that number of sidereal months counted exceeds the number of anomalistic months counted by exactly one. This happens after about 3233 days.
This precession causes the full moon cycle to be over a month longer than a sidereal year.
There are approximately two such lunar precession cycles in a saros cycle.
This is to be distinguished from precession of the lunar nodes of the lunar orbit on the plane of the ecliptic. This is mainly caused by the oblation of the Earth; it is the period of the main nutation term in the orientation of the polar axis of the Earth. This nodal period is about twice as long as the apsidal precession period discussed above. After the nodal period, the number of draconic months counted exceed the number of sidereal months counted by exactly one: this happens after about 6793 days (18.6 years).
Definition of orbital parameters.
Semi-major axis ~384 748 km
Distance at perigee ~364 397 km
Distance at apogee ~406 731 km
Mean eccentricity 0.0549006 (0.044 – 0.067)
Mean inclination of orbit to ecliptic 5.145°
Mean obliquity 6.688°
Mean inclination of lunar equator to ecliptic 1.543°
Period of precession of nodes 18.5996 years
Period of recession of line of apsides 8.8504 years
The Moon is moving away from us about 3.8 centimeters per year or 1.5 inches per year. That means its stabilizing influence and the tidal effect is lessening albeit by a tiny amount but still a factor.
The mean distance of the Moon from the earth these days is 238,855 miles (it wobbles a bit and its orbit is not circular so sometimes it is closer and sometimes it is farther, depending on where it is in its orbit). That would seem to indicate that IF the moon had continued at a CONSTANT recession rate of 4 centimeters a years, then over 1 billion years the distance has increased about 10 percent, give or take a few tenths.
Best current estimates for the Moon's age are about 4.5 billion years, so that would mean (if the 4 centimeters a year were constant) the distance receded would be 111,148 miles, or slightly less than 50% of the distance it is at now.
Distance to the Sun
At perihelion (nearest point) the Earth/Sun distance is about 146,000,000 km, and at aphelion (farthest point) it's about 152,000,000 km. Distance reduces the intensity of the energy received.
Orbit around the Sun varies the distance too, and that varies the energy received at the top of the atmosphere from a maximum 1417 W/m2 in early January to a minimum of about 1324 W/m2 in early July.
Length of day
Length of day is another contributor to the amount of sunlight we get at higher latitudes, longer in summer means more and shorter in winter means less. In summer the distance sunlight travels through the atmosphere is less so the air is less warmed but the ground is more so as the intensity is greater (less diffused and reflected by air molecules and aerosols like sulphur and dust and more focussed as a given sunbeam is nearer to vertical).
Day length also varies. It has been closely related to temperature change.
In the game of global warming, backward flipping, glaciation, and grand kid icicle toasties, values have to be associated to all these factors but there are other considerations.
Don't worry, I'll get to co2 eventually, but it isn't in sight yet