HOAPS: A Satellite based Climate Data Record of Ocean-Atmosphere Interaction Parameters

The Hamburg Ocean-Atmosphere Parameters and Fluxes from Satellite Data (HOAPS) data set provides a long-term, consistent suite of global ocean-atmosphere climate variables over ice-free oceans derived from satellite passive microwave observations. Designed to support climate monitoring, air-sea interaction studies, and model evaluation, HOAPS offers more than three decades of key parameters such as vertically integrated water vapor, evaporation, near surface specific humidity, near surface wind speed, freshwater flux, latent heat flux, and, recently implemented, liquid water path.

A defining feature of HOAPS is its inter-sensor calibration and physically consistent algorithms, ensuring that all products are produced using a uniform retrieval framework, minimizing artificial trends and discontinuities.

In this presentation, we will focus on the upcoming HOAPS release (HOAPS v5.0), outline recent methodological updates such as newly implemented data sources, updates of the retrieval and radiative transfer model including a new bias correction scheme, improved uncertainty propagation, and more. Additionally, we will demonstrate the usefulness of the dataset through selected examples that highlight variability in the global water cycle. We will also discuss the implementation of a continuous extension of the dataset. HOAPS sustains to serve as a robust satellite-based reference for climate studies of air-sea fluxes and ocean-atmosphere coupling and more.