Final answer:
The global temperature increased by approximately 5 degrees Celsius from the ice age to the beginning of agriculture.
Step-by-step explanation:
The global temperature increase between the ice age and the beginning of agriculture is approximately 5 degrees Celsius. The last ice age ended about 14,000 years ago, and at that time, the average global temperature was around 6 degrees Celsius lower than it is today. Given the importance of understanding climate patterns for agriculture, this piece of information is particularly relevant when studying the transition from hunter-gatherer societies to agricultural ones.