Tmicro-APEX, an Addition to APEX Floats to Measure Temperature Microstructure

University Of Washington, Seattle WA

Investigators

Abstract

The PI's propose to develop a capability to measure temperature microstructure over large areas and for extended times. This will permit sampling suspected mixing 'hot spots' over larger areas and for longer periods than affordable with ships, measuring in areas not frequented by ships, or where the weather is too severe for ship-based observations. To meet this scientific objective, the PI's propose to add temperature microstructure as one of the optional sensors available with Autonomous Profiling Explorers (APEXs) floats. Because these floats can be programmed to restrict their profiling range to stay within water masses, they will allow simultaneous Lagrangian observations of mixing rates and T,S changes. The addition would consist of two thermistors to detect the microstructure, a small external signal-conditioning package, an internal electronics board and software for processing the data and mounts for additional batteries and modification to the ballasting. The data will be added to the existing data stream transmitted every time a float surfaces. Only a small amount of additional processing will be required ashore. Broader Impacts The Tmicro-APEX floats could allow for global spatial coverage of turbulent mixing variability in the ocean and help to identify its temporal variability. This global understanding of ocean mixing from measurements will help constrain the mixing rates that are parameterized in global and regional ocean models. The proposed instrumentation development will offer the opportunity to have a standardized microstructure measurement package accessible to a broad sector of the experimental physical oceanographic community. It should stimulate numerous investigations that overtime will provide a significantly improved understanding of the global dissipation processes and their variability.