[A-CG40] Earth System Observation Impacts on Climate and Ocean Predictions

[ACG40-P02] Probabilitisic Predictions of Shallow Water Sound Ducts in the Global Ocean

*Kenneth Andrew Peterson¹, Gregory C. Smith¹, Kamel Chikhar², Andrea Storto³, Cristina Tollefsen⁴ (1.RPN-EM, ECCC, 2.MSC, ECCC, 3.CNR, 4.CU)

Keywords:Shallow water acoustic ducts, Sound speed profiles, Sub-surface temperature and salinity observations, Ensemble Ocean Analysis, Probabilistic Forecasting

Detection of secondary acoustic ducts in the ocean have important consequences for naval and marine applications. Construction of sound speed profiles from temperature and salinity profiles, with subsequent determination of the presence of local minimum in the sound profiles from global ocean analysis offers the opportunity to detect the possible existence of sound ducts. Given the often intermittent nature of the phenomena, a probabilistic approach may likely be an optimal approach for detection. Using an experimental ensemble ocean analysis developed at Environment and Climate Change Canada, we investigate the skill of probabilistic detection of shallow water sound ducts from both the ensemble analysis, and from climatological considerations, using a global database of observed sub-surface temperature and salinity profiles (primarily from Argo floats). Gains in prediction skill over using solely deterministic methods are shown.