Which phenomenon is a major ocean–atmosphere teleconnection that influences global rainfall and storm tracks?

• A. El Niño-Southern Oscillation (ENSO) influences global rainfall and storm tracks.
• B. The Arctic Oscillation determines global rainfall.
• C. The Madden-Julian Oscillation controls all storm tracks worldwide.
• D. North Atlantic Oscillation is unrelated to rainfall patterns.

Answer: (A)

The main idea here is how distant ocean conditions influence climate elsewhere through ocean–atmosphere connections. ENSO is the strongest of these connections: when the tropical Pacific warms (El Niño), the atmospheric circulation shifts, altering where convection occurs and steering jet streams and storm tracks around the world. This reshapes rainfall patterns in many regions and can move storm tracks across continents. The opposite phase (La Niña) reverses many of these effects. Because ENSO involves large-scale changes in tropical ocean temperatures that propagate through the atmosphere to affect weather far from the Pacific, it stands out as the major global teleconnection for rainfall and storm tracks.

Other patterns tend to have more regional or shorter-term influences and don’t produce the same global-scale rainfall and storm-track signals.