A Monthly Index for the Large‐Scale Sea Surface Temperature Gradient Across the Separated Gulf Stream

Abstract The strong sea‐surface temperature (SST) gradient associated with the Gulf Stream (GS) is widely acknowledged to play an important role in shaping mid‐latitude weather and climate. Despite this, index for GS SST has not yet been standardized literature. This paper introduces a monthly large‐scale across separated based on time‐varying position detected from height. Analysis suggests that variations average throughout year result primarily variability north of GS, little contribution south. exhibits weak periodicity at ∼2 years. Sea level pressure turbulent heat flux patterns suggest related atmospheric (rather than oceanic) forcing. Ocean‐to‐atmosphere feedback does persist year, but there some evidence wintertime feedback.