Talk Abstract:
In many parts of the global ocean, density compensated temperature (T) and salinity (S) anomalies, known as ocean spice, highlight processes that interleave, stir and eventually mix water from different sources. The unique spatial and temporal structure of upper ocean spice patterns is set by the large-scale dynamics and the balance between different frontal processes, such as subduction, turbulent mixing, and atmospheric forcing that create, distribute and destroy spice. Spice variability also plays a substantial role in modulating and sometimes creating upper ocean acoustic ducts as it modifies the sound speed profile. Not all interactions between the larger-scale dynamic process and mixing mechanisms are well characterized, and the answer may vary between different oceanic regions and across time. Using a decade of upper ocean high-resolution data from multiple ocean basins: the Bay of Bengal, the Nordic Sea, the South China Sea, and the Beaufort Sea, we compare and contrast spice distribution in fronts with different temperature and salinity ranges and analyze the frontal processes identified in each region. We aim to combine recent findings with available large datasets to establish global patterns of spice variance, production, and destruction and further our understanding of the impact spice has on sound propagation. Understanding how spice creation, subduction, stirring, and mixing conspire to set the space and time scales of sound speed profiles opens the door toward improving the forecast of sound speed channels and scattering. Beyond sound speed, studying what sets spice distribution will help constrain global heat and salt budgets.
All seminars this quarter will be in a hybrid format. Recordings available upon request.