Instructions: Given a scientific passage and an answer, generate a question for the given answer.
Input: Passage: Large ocean currents can have a big impact on the climate of nearby coasts. The Gulf Stream, for example, carries warm water from near the equator up the eastern coast of North America. Look at the map in Figure below . It shows how the Gulf Stream warms both the water and land along the coast. Answer: large ocean currents
Output:
Which factor has a big impact on coastal climates?