Wind stress and heat flux contributions to decadal temperature changes and sea level on the North Atlantic ocean over 1993-2011 based on ECCO solutions and its adjoint

William LLOVEL (JPL/NASA/UCLA, United States)


Ichiro Fukumori (JPL/NASA, USA); Ou Wang (JPL/NASA, USA); Ian Fenty (JPL/NASA, USA); Gael Forget (MIT, USA)

Event: 2014 Ocean Surface Topography Science Team Meeting

Session: Science Results from Satellite Altimetry: Regional and basin-scale processes and sea level rise

Presentation type: Type Poster

Since 1993 and based on satellite altimetry data, decadal sea level trends display a large regional variability. Some regions experience a sea level rise (e.g., the west tropical Pacific ocean, the subpolar north Atlantic ocean ...) whereas other regions experience a sea level drop (e.g., the east tropical Pacific Ocean, golf of Alaska...). Those sea level trends appear to be steric in nature. Moreover, steric changes appear to be mainly thermosteric, although halosteric effects can reduce or enhance thermosteric changes in some specific regions (Stammer et al., 2013). Understanding and quantifying the processes involved in regional sea level changes are important tasks to better constrain and ascertain the physical processes involved in regional sea level changes and then, improve future predictions to anticipate potential coastal impacts. In this present study, we investigate the decadal upper ocean warming (above 700m depth) of the North Atlantic subpolar gyre over 1993-2011. For that purpose, we investigate the ocean heat content change and its origin by analyzing Estimating the Circulation and Climate of the Ocean (ECCO, Wunsch et al., 2009) and its adjoint. The adjoint provides an efficient means to evaluate the sensitivity of the model to its components, including model's forcing. Thus, we assess the respective contributions of wind stress and heat flux to the upper ocean warming and its contribution to sea level from 1993 to 2011.
William LLOVEL
United States