OCNET global daily Chlorophyll-a products

We constructed the Ocean Chl-a Reconstruction Neural Ensemble Network (OCNET) model to generate global daily chlorophyll-a (Chl-a) concentration data. The model utilized the climatological data from the Ocean Color Climate Change Initiative (OCCCI) version 6 as the background field and the NOAA MSL12 spatiotemporally continuous daily-scale data as the target dataset. Sea surface temperature (SST), salinity (SAL), photosynthetically available radiation (PAR), and sea surface pressure (SSP) were selected as the primary environmental factors influencing phytoplankton growth and distribution for data reconstruction. Ultimately, we developed a daily-scale global ocean surface Chl-a concentration dataset for the period 2001–2023, with a spatial resolution of 0.25°. This dataset is spatiotemporally continuous, spans a long time period, and shows high consistency with satellite data products in regions with available data. It also addresses the issue of severe data gaps in satellite daily-scale products, providing critical information for long-term and large-scale studies of marine phytoplankton. Compared with traditional interpolation methods, the OCNET model fully leverages the environmental information provided by ERA5 reanalysis data and MODIS satellite data to reconstruct Chl-a concentration data. Moreover, the model is not limited by the size of the marine area or the temporal coverage of the original Chl-a concentration dataset. Provided that reliable environmental variable data are available, the model can serve as an important reference for reconstructing historical Chl-a data and predicting future changes in Chl-a concentration.

The latitude and longitude of the left bottom corner, the number of rows and columns, and grid cells information are all included in each netCDF file. In addition to the Chl-a data generated by the OCNET model, we also provide the OCNET model algorithm (based on Matlab version 2022b), example datasets, and the detection results of Marine High Chlorophyll-a (Chl-a) Events.