[cicero2k]

My theory: comet impact 12,800 YA.

Then MicroNova of sun, 1500 years later to melt.

[Openurmind]

Since previous glacial/interglacial periods happened on a regular cycle, I am leaning towards the pulse quasar event on a regular interval theory.

[JimRed]

My theory: comet impact 12,800 YA.

Then MicroNova of sun, 1500 years later to melt.

OR, Impact, several years of reduced sunlight followed by residual airborne gases or particulate matter holding in the warmth after the initial cooling to reverse the process.

Must have been tough to be a hunter/gatherer back then!