What climate phenomenon occurs every two to seven years in the Pacific Ocean and affects global weather patterns?

The phenomenon that occurs every two to seven years in the Pacific Ocean and has significant implications on global weather patterns is El Niño. This climate event is characterized by the warming of surface waters in the central and eastern tropical Pacific, which affects atmospheric circulation and can lead to notable shifts in weather patterns worldwide.

During El Niño events, the warmer ocean temperatures can disrupt the normal trade winds, leading to a cascade of effects such as changes in precipitation patterns, increased storm activity in certain regions, and droughts in others. These alterations can have major impacts on agriculture, ecosystems, and even economies around the globe, making it a critical aspect of climatology.

La Niña, while also a significant climate phenomenon, represents the opposite of El Niño with cooler ocean temperatures in the same regions and its effects, although important, are distinct and occur at different intervals. Monsoons, on the other hand, are seasonal wind systems that bring wet and dry periods and are not tied to the same oceanic warming cycles. Climate change refers to long-term alterations in climate patterns and is not specifically defined by a periodic event like El Niño.