What is a tempreture?Just doing some back of the napkin calculations.
As you may be familiar the chart of global tempreture based on ice core samples covering the passed 650,000 years shows an irregular and roughly 150,000 year cycling pattern. Begs the question what geological or astronomical effect has that duration of pattern. Nothing known has that pattern per se. But applying orbital dynamics to the time pattern gets an orbit of 40 AU. That is to say something orbiting at 30 AU would have a period of about 150,000 years.
Most sources cite the span of the Kuiper Belt at between 30 AU (about the orbit of Neptune) to about 50 AU (a little less than twice as far from the sun as Neptune).
So 40 AU is smack dab in the middle of the Kuiper Belt. A couple of, I would imagine, large bodies on eliptical orbits perturbing each other and the rest of the belt could send comets into the solar system on a roughly cyclical pattern of about 150,000 years.
That's the only source I know of that has that periodocity and concievable power to cause the 150,000 year cyclicity of earth tempreture as observed.