In situ temperature, stratification, and coral bleaching survey data from the 2022 and 2024 marine heatwaves in Hong Kong

This dataset contains coral bleaching survey data, high-resolution in situ
temperature measurements, CTD-derived stratification profiles, and
satellite sea surface temperature records collected from three coral reef
sites in Hong Kong (Bluff Island, Sharp Island, and Tung Ping Chau) during
the 2022 and 2024 marine heatwaves. The data include raw and processed
bleaching observations at the colony level (later standardised to genus
level for analysis), fixed logger temperature time series (SBE56 and
miniDOT), camera-mounted DEFI logger measurements of depth, temperature,
and light during transects, seasonal CTD transects for water column
structure and buoyancy frequency calculations, and NOAA Coral Reef Watch
satellite temperature products used to derive Degree Heating Days and
Degree Heating Weeks. Environmental data are provided in MATLAB (.mat)
format and bleaching observations in .csv format. Post-processed datasets
used for Bayesian modelling are included alongside the raw survey data.
The dataset enables examination of depth-dependent thermal variability,
heat accumulation metrics, stratification intensity, and bleaching
prevalence across sites and years. Scripts in R and MATLAB are provided to
reproduce statistical modelling and environmental processing. All data
were collected from publicly accessible reef sites in Hong Kong without
manipulation of organisms. No personal data are included. The dataset can
be reused to investigate coral bleaching dynamics, marine heatwave
impacts, stratification-driven thermal refugia, and methodological
comparisons between satellite and in situ temperature metrics in marginal
subtropical reef systems.