Fact 1: Unequal heating of Earth 's surface by the Sun causes global wind patterns.

Fact 2: Winds of 74 mph are the standard for a hurricane.

Given the two facts above, answer the question "What forms due to unequal heating of Earth's surface by the Sun?" with the following options: 
- rays or beams
 - hurricanes
 - power stations
 - It expands
 - climate
 - The atmosphere
 - an object
 - energy barrier


 

  hurricanes       