Global maps of Forel–Ule index, hue angle and Secchi disk depth derived from 21 years of monthly ESA Ocean Colour Climate Change Initiative data

Abstract. We document the development and public release of a new dataset (1997–2018), consisting global maps Forel–Ule index, hue angle Secchi disk depth. Source data come from European Space Agency (ESA) Ocean Colour (OC) Climate Change Initiative (CCI), which is providing merged multi-sensor mid-resolution sensors in operation at specific time 1997 to present day. Multi-sensor satellite datasets are advantageous tools for ecological studies because they increase probabilities cloud-free over given region as multiple satellites whose overpass times differ by few hours combined. Moreover, data-merging heritage can expand duration series indefinitely, allows calculation significant trends. Additionally, remapped consistently analysis-ready scientists. Also, products described this article have exclusive advantage being linkable situ historic observations thus enabling construction very long series. Monthly presented spatial resolution ?4 km Equator available PANGAEA (https://doi.org/10.1594/PANGAEA.904266; Pitarch et al., 2019a). Two smaller easier-to-handle test been produced former: 1? another one North Atlantic 0.25? resolution. The computer code generation depth remote-sensing reflectance also shared https://doi.org/10.5281/zenodo.4439646 (Pitarch 2021) be easily set loop mode batch calculations.