I realized this a few years ago. This is my theory although I am 100% certain it is not a theory but fact however this is science and without hard evidence it is still theory.
There are many theories about how this can occur and the most popular is the theory involving slight variations in earths orbit around the sun but this is just bad science and after you read this you will understand why.
When earth is healthy with little negative influence from mankind earths forests thrive. When this occurs the air becomes rich with oxygen and very little carbon causing too much of the suns heat to escape as there is not enough carbon in the atmosphere to trap the heat. This cooling effect slows evaporation which Decreases the amount of rain in the atmosphere and as this happens fresh water sources at a lower and lower latitude freeze and majority of the moisture is out of the atmosphere. This is when the ice age starts. During the ice age The northern forests die and anywhere else the ground remains frozen for an extended period of time. I do not know one thing though which is how far south this ice cover extends it must very from ice age to ice age. This was why an ice age occurs. 100%
Now my theory on how earth recovers from an ice age.
An ice age does not mean that the entire planet is covered in I believe. My belief and many’s belief is that the equator remains ice-free however may experience snow and freezing rain frequently. You see Mother Nature is constantly creating balance and in a perfect world with zero negative influence from mankind she knows exactly which forests need rain, which forests need to burn and any other occurrence that needs to happen. this Is important because along the equator there has to be wildfires so that the earth can get warm again. And maybe I’m wrong about variations in earths orbit not causing an ice age. Perhaps these variation in conjunction with a thriving planet is what is needed to start the ice age.
Thanks
