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Sunday, Jul. 6, 2025

Is global warming just due to El Niño?

Sue Bin Park, Skeptical Science
no

El Nino Southern Oscillation is a short-term and cyclical weather phenomenon caused by alternating wind patterns that result in heat exchange between the ocean and the atmosphere; it cannot explain long-term warming.

El Nino originates when westward moving trade winds weaken, allowing warm surface waters to shift east across the tropical Pacific. This reverses the La Nina pattern, where trade winds push warm surface water toward Asia, upwelling cold water off the South American coast

During El Nino, heat is transferred from the ocean to the atmosphere, causing warming, while in La Nina, heat moves from the atmosphere to the ocean, causing cooling. Energy is moved around the climate system without adding any heat.

In contrast, climate research indicates human-caused CO2 is the primary driver of today’s warming. Human activities that increase greenhouse concentrations in the atmosphere cause less heat to escape the atmosphere, resulting in additional and non-cyclical warming.

See a full discussion of this at Skeptical Science

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