The Gulf Stream and Kuroshio Current are synchronized

Area of Science:

• Oceanography
• Climate Science
• Atmospheric Science

Background:

• Sea surface temperatures along major boundary currents like the Gulf Stream and Kuroshio Current exhibit synchronized decadal variability.
• This synchronization, termed boundary current synchronization (BCS), is a notable feature in climate system dynamics.

Purpose of the Study:

• To investigate the phenomenon of boundary current synchronization (BCS).
• To understand the relationship between ocean currents, atmospheric jet streams, and sea surface temperature synchronicity.
• To determine if BCS is reproducible in climate models and identify its underlying mechanisms.

Main Methods:

• Analysis of observational data on sea surface temperatures.
• Validation using high-resolution global climate model simulations.
• Numerical simulations with a conceptual model and an atmospheric general circulation model.

Main Results:

• Boundary current synchronization (BCS) is accurately reproduced in climate models.
• BCS is strongly associated with meridional migrations of the atmospheric jet stream.
• Shifts in ocean current strength and path, driven by jet stream changes, cause synchronized sea surface temperatures.
• Simulations support BCS as an interbasin air-sea coupled mode.

Conclusions:

• Boundary current synchronization (BCS) is a robust climate phenomenon driven by coupled air-sea interactions.
• Atmospheric jet stream variability plays a crucial role in mediating decadal sea surface temperature synchronicity in boundary currents.
• The findings enhance understanding of large-scale climate variability and teleconnections.