Resolving the Short-term Persistence of Oceanographic Measurements from an Autonomous Underwater Vehicle in the Central Red Sea, October 2017

Autonomous Underwater Vehicles (gliders) have added a wealth of knowledge to our understanding of the oceans across the world. This research presents a new multi-method statistical process for resolving short-term persistence [features and temporal/spatial scales of concern] of observed oceanographic variables from glider deployments in the central Red Sea. Short-term persistence can be considered as the minimum characteristic time scale of observable patterns in the study area. The characteristic time scales can then be used as a method to determine the most important processes influencing circulation and variable distributions within the central Red Sea. Autocorrelation, Error X, and a variation of the Wilcoxon rank sum have been applied to data collected from the central Red Sea in October of 2017 along specific depth levels (6 m, 75 m, and 150 m) and density surfaces (25.75 kg/m³, 26.75 kg/m³, and 27.75 kg/m³). The presented parameters include temperature, salinity, density, chlorophyll a, and dissolved oxygen. The three methods show similar patterns of correlation and dependency as the measured time lag increases at most of the reported specific depth levels and density surfaces. At least two of the three statistical processes converge on a short-term persistence resolution of 14-18 days across at the 75 m depth level, the 26.75 kg/m³ density surface, and for the variables of chlorophyll a and dissolved oxygen at the 27.75 kg/m³ density surface.