Around 650 million years ago, the Earth was covered from pole to pole with glaciers during a period referred to as Snowball Earth. Identify and describe a set of 3 realistic global scale feedback mechanisms that address the following:
a. A feedback mechanism that allowed the Earth to descend into a global glaciation
b. A feedback mechanism that kept the Earth in a permanent glaciation for millions of years
c. A feedback mechanism that allowed the Earth to escape from the glacial period to the warm period that followed.