Dynamic Sea Level Variability Due to Seasonal River Discharge: A Preliminary Global Ocean Model Study

Abstract

AbstractRiver discharge is an important driver of the coastal ocean circulation. However, the influence of variable effects on large‐scale sea level related to ocean dynamics is not well understood. We perform numerical experiments using a coarse ( °) global ocean state estimate to quantify effects on the seasonal cycle in dynamic over the global ocean. Forcing by drives substantial dynamic signals ( cm) on regional scales around major rivers (e.g., Amazon, Ganges, Brahmaputra, Irrawaddy, Ob, Lena, and Yenisei). Modeled changes largely reflect halosteric (salinity) effects, which are partly affected by transport processes involving planetary waves and advection. The modeled response to is informative for interpreting observations from satellite altimetry and tide gauges, explaining 10–20% of the regional‐scale seasonal data variance around some major rivers. Future studies should consider finer‐resolution models and forcing on nonseasonal time scales of relevance to climate.