Examining Ocean Mixing Dynamics at the Namonuito Guyot and Nam 2. Atoll

Abstract

This study investigates the impact of guyots and atolls on ocean currents and mixing processes in the Caroline Islands, Micronesia. The hypothesis is that atolls enhance vertical and horizontal mixing more effectively than guyots due to their surface-reaching morphology. To test this hypothesis, vertical profiling was conducted using underway CTD (Conductivity, Temperature, and Depth) and ADCP (Acoustic Doppler Current Profiler), along with calculations of mixed layer depth, stratification, mixing rate measurements, and Thorpe scale at Namonuito Guyot and an unnamed atoll near the guyot, referred to as Nam. 2 Atoll in this study. The findings reveal significant differences in mixing dynamics between the two features. The atoll exhibited stronger mixing and a more uniform mixed layer, driven by its interaction with surface currents and waves. In contrast, the guyot showed more stratified layers and weaker mixing, reflecting its submerged nature and limited interaction with surface processes. These results provide insights into the physical processes governing these geological features and their influence on ocean circulation, highlighting the distinct roles of guyots and atolls in shaping ocean mixing dynamics.