Data quality control documentation for coastal wave buoys, Version 1.0.

Abstract

Sustained, near real-time (NRT) observations of waves in coastal regions are an essential prerequisite to monitor, predict, and forecast coastal hazards that threaten coastal populations, infrastructure and marine operations. Additionally, NRT temperature observations in coastal regions are required to understand the impacts of environmental disturbances (both extreme events and long-term changes) on coastal ecosystems. To address this observational gap around Australia’s coastline, the Integrated Marine Observing System (IMOS) created the Coastal Wave Buoy facility in 2024. As of December 2025, the wave buoy network consists of 23 sites situated at strategic, high-priority locations throughout Australia’s coastal waters (10-70 m depths).

The IMOS Coastal Wave Buoy observation platform is the Sofar Spotter, a small-format GNSS (Global Navigation Satellite System) wave buoy with a temperature sensor embedded into the bottom of the hull. The Spotter collects GNSS data at 2.5 Hz and then performs on-board spectral analysis to produce timeseries of integrated and spectral wave parameters. Surface water temperature is collected at 1 Hz and averaged every minute on-board. The wave and temperature measurements are recorded locally on the buoy’s internal memory card (delayed mode, DM), whereas summarised wave and temperature statistics (including spectral wave parameters) are transmitted to Sofar’s cloud platform via cellular and/or satellite Iridium networks (near real-time, NRT).

This document outlines the data management and quality control steps that are used to post-process raw data collected by the wave buoys and to archive it on Australia’s Ocean Data Network (AODN). The IMOS Coastal Wave Buoy facility supports both NRT and DM data streams, each of which undergoes quality control and assessment in accordance with best-practice guidelines outlined by the Integrated Ocean Observing System (IOOS) before being archived on AODN. To facilitate wider use of these data processing workflows by other organisations in Australia and globally, the IMOS Coastal Wave Buoy code repository is publicly available on GitHub.