Atmospheric patterns forcing two regimes of arctic circulation: A return to anticyclonic conditions?

Atmospheric sea level pressure (SLP) patterns associated with two regimes of ice-ocean circulation are identified by sorting the data into bins depending on whether modeled Arctic Ocean circulation was anticyclonic or cyclonic. The transition between regimes is a zonally symmetric SLP cell with maximum amplitude at the north pole. From 1946 to 1997, four anticyclonic and four cyclonic regimes track the Arctic Ocean SLP oscillation. Recent SLP data suggest that the ocean-atmosphere system will shift, or has already shifted, to an anticyclonic state.