Deep-Ocean Temperature data from a mooring in the Southeast Pacific (85°W, 20°S), 2012 - 2025

A time series of deep-ocean temperature measurements is provided, spanning 13 years (2012-2025) at depths from 4200 to 4500 m in the Southeast Pacific. The measurements come from temperature sensors mounted above the anchor of moorings at the Stratus Ocean Reference Station site near 22°S, 85°W, off the coast of Chile. Long-term, deep-ocean temperature monitoring is crucial for understanding the ocean’s role in climate variability and the storage of heat in the deep ocean. While observation of the ocean surface is relatively accessible via both in-situ and remote sensing, high-temporal resolution, continuous temperature records from abyssal depth remain rare due to technical challenges in sustained deployments and sensor stability. The addition of calibrated internally-recording temperature sensors above the anchor of deep-ocean moorings provides a means of obtaining high-temporal resolution records. Quality controlling and merging records from multiple mooring deployments at the same site results in a continuous time series. Dual sensors are deployed, allowing measurement precision to be estimated from the difference between temperature measurements. Processing steps include timing checks, automated spike detection, systematic multi-sensor validation, statistical validation, human-in-the-loop quality control, and merging protocols. Extensive metadata are included, and latitude, longitude and depth are provided on the same time base as temperature for ease of analysis.