The Antarctic ozone hole and the pattern effect on climate sensitivity

Area of Science:

• Climate Science
• Atmospheric Science
• Oceanography

Background:

• The tropical Pacific has cooled anomalously since 1980, contrasting with broader tropical warming.
• This cooling impacts midlatitude weather and reduces climate sensitivity due to increased low clouds over cooler eastern tropical Pacific waters.
• Previous models linked Southern Ocean cooling to eastern tropical Pacific temperature changes.

Purpose of the Study:

• To investigate the connection between Antarctic ozone hole-induced surface wind anomalies and tropical Pacific cooling.
• To explore the role of Southern Ocean temperatures in modulating eastern tropical Pacific climate.
• To determine if Antarctic ozone hole onset correlates with observed tropical Pacific cooling.

Main Methods:

• Analysis of short-term variability in the Southern Annular Mode (SAM) of zonal wind.
• Correlation analysis between Southern Ocean surface zonal wind anomalies, Southern Ocean temperatures, and eastern tropical Pacific temperatures.
• Utilizing observational data to link atmospheric and oceanic changes.

Main Results:

• A significant association was found between surface zonal wind variations over the Southern Ocean and cooling in the eastern tropical Pacific.
• Southern Ocean cooling was demonstrably linked to these wind anomalies.
• The observed cooling patterns suggest a connection to the timing of the Antarctic ozone hole's development.

Conclusions:

• Surface wind anomalies driven by the Antarctic ozone hole can induce Southern Ocean cooling, which extends into the tropics.
• The cooling of the eastern tropical Pacific since approximately 1980 may be linked to the onset and persistence of the Antarctic ozone hole.
• This research highlights a teleconnection between polar ozone depletion and tropical climate variability.