What is the cycle we see and what is the cause of this cyclically of global temperatures and what does this say about a potential future glacial age?

In the last 450,000 years the earth has had at least 4 major ice age cycles .What is the cycle we see and what is the cause of this cyclically of global temperatures and what does this say about a potential future glacial age?
50
L — 40 a) 30 a) u, 20°
10′
Glacial-interglacial cycles over the past 450,000 years
Inter- Inter-Inter- glacial Inter- glacial Into, glacial glacial A ill I ill glad .1 1 ILI I I IIII IMIll ril 111 ■ it i Glacial Glacial Glacial Glacial
400.000
300,000
200.000 Years Ago
100,000
Interglacials
Glacials
Today

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