Interannual heat budget of the California Current region

An upper-ocean heat budget is developed for the California Current region. The heat storage rate is estimated from WOCE XBT measurements along a ship track that cuts across the California Current, while heat advection terms are estimated from satellite (scatterometer winds, altimeteric SSH, and infrared SST). Various existing heat flux products are compared based on their performance in the heat budget; because all are available globally, their evaluation is useful for ocean modelers. The heat flux products (GSST-F, HOAPS, J-OFURO, NCEP, ECMWF, and COADS) differ by their input data source (satellite, ship, or weather model) as well as by bulk flux algorithm used. The time period for the interannual heat budget is 1990-present, which includes an extreme El Nino event. Changes in the budget terms during the El Nino are presented, with a focus on variability in the components of the surface heat flux. These changes are connected to changes in background conditions, such as the width of the California Current, the strength of its flow, and the overlying wind field.