Interannual variability of winter-spring temperature in the Middle Atlantic Bight : relative contributions of atmospheric and oceanic processes

Abstract

Relative contributions between the local atmospheric and oceanic processes on the interannual variability of winter-spring shelf temperature in the Middle Atlantic Bight (MAB) are investigated based on a regional ocean model. The model demonstrates sufficient capability to realistically simulate the interannual temperature changes during 2003–2014. On interannual time scales, the mean winter/spring temperature in the MAB is determined by the combination of the initial temperature at the beginning of the season and the mean cumulative air-sea flux, while the mean cumulative ocean advective flux plays a secondary role. In spite of the overall importance of air-sea flux in determining the winter and spring temperature, the relative contributions between air-sea flux and ocean advective flux on the evolution of the temperature anomaly in each individual year varies. The predictability of spring (April–June) temperature based on winter (January–March) temperature is weak because the temporal decorrelation time scale changes significantly from year to year. Both the highly variable shelf temperature and its decorrelation time scale are affected by the changes in the relative contributions between the air-sea flux and ocean advective flux.