Dwindling Arctic Sea Ice May Affect Tropical Weather Patterns.

The rapid decline of Arctic sea ice during the last couple of decades has spurred climate scientists to study how that meltdown influences the rest of the planet, and a new study suggests that the effects may extend deep into the tropics.

Researchers have found a pattern between sea ice melting
and El Niño in the Central Pacific Ocean, linked by winds.

The study, published Monday in the journal Proceedings of the National Academy of Sciences, detected a pattern that links sea ice decline since the late 1990s with more frequent warm cycles in the Central Pacific Ocean. The surges of ocean heating in that region can disrupt the climate, affecting drought, flood and hurricane patterns around the world. 

Winds are the link between the melting ice and the tropics. The researchers posit that the Arctic Ocean has warmed up so much in the last 20 years that warm, late-summer sea surface air forms powerful convective towers, rising to the stratosphere. When the air falls back toward the equatorial Pacific, it intensifies prevailing east-to-west trade winds that push warm water toward Asia and Oceana, giving birth to a Central Pacific El Niño, a geographically specific variation of  the well-documented Pacific warming and cooling cycle that is a key driver of the global climate.

The study found a secondary effect. The atmospheric roller coaster rebounds back north, and may weaken a weather pattern near Alaska that steers Pacific storms toward the West Coast.  

Read the Inside Climate News story by Bob Berwyn - “Dwindling Arctic Sea Ice May Affect Tropical Weather Patterns.”