Question: how cold did the earth go during the ice age?

Freya Addison answered on 22 Nov 2019:

In the 1600-1700s there was a mini ice age over Europe, this was enough to freeze the Thames, at its coldest it was ~1degree cooler. During the larger ice ages it was -3 to -6 degrees cooler! These changes are from ice core temperatures. I recommend this website for further information: http://www.antarcticglaciers.org/glaciers-and-climate/ice-cores/ice-core-basics/
For a bit of context, the sun goes through a solar cycle of 11 years, to a minimum and maximum, the difference in radiation between these periods causes a change in temperate globally by ~0.2degrees.