Ocean Productivity available to Fish (OPFish) - Global Ocean MONTHLY - 2003-2020 (% of daily favorable occurrence, 1/24° by 1/24°)

As a proxy for potential fish production, the Ocean Productivity available to Fish (OPFish) was successfully tested against commercial and scientific spatial fisheries datasets in the European Seas, notably in detecting local overfishing. The OPFish uses the productivity frontal features derived from chlorophyll-a horizontal gradients, which characterize 10-20% of the global phytoplankton production that effectively fuels higher trophic levels . This satellite-derived proxy of potential fish feeding was shown to greatly facilitate the identification of local fishing opportunities by quantifying the useful fraction of plankton production that could support fisheries catches. More information: https://fishreg.jrc.ec.europa.eu/fish-habitat

OPFish was calculated using daily chlorophyll-a (mg.m−3) data from the MODIS-Aqua ocean color sensor (2003–2016; 1/24° resolution) and the Ocean Color Index (OCI) algorithm (Hu et al., 2012). These data was extracted from the NASA portal (https://oceancolor.gsfc.nasa.gov/l3/) with the archive reprocessing of January 2018.
The OPFish has daily values from 0 to 1 following the equation:

OPFish = C_g * C_r * DL (see details in Druon et al. 2021)

where OPFish = Ocean Productivity available to Fish (potential fish production in relative level),
Cg = linear function derived from the norm of the horizontal gradient of chlorophyll-a, from 0 to 1,
Cr = value 1 if within the suitable chlorophyll-a range, and 0 otherwise,
DL = relative day length duration from 0 to 1 (day length in hours divided by 24).

Hu, C., Lee, Z., & Franz, B. (2012). Chlorophyll a algorithms for oligotrophic oceans: A novel approach based on three-band reflectance difference. Journal of Geophysical Research: Oceans, 117, 1–25. doi:10.1029/2011JC007395
Druon JN, Gascuel D, Gibin M, Zanzi A, Fromentin JM, Colloca F, Hélaouët P, Coll M, Mannini A, Bluemel J, Piroddi C, Bastardie F, Macias-Moy D, Vasilakopoulos P, Winker H, Serpetti N, Guillen J, Palialexis A, Gras M, Hekim Z, Dubroca L, Pinto C, Steenbeeck J and Martinsohn J (2021) Mesoscale productivity fronts and local fishing opportunities in the European Seas. Fish and Fisheries, 00, 1-21, DOI:10.1111/faf.12585
https://onlinelibrary.wiley.com/doi/full/10.1111/faf.12585