Microplankton fraction (Sfm) estimated form satellite output (OC-CCI), links to netCDF files

We provide satellite output that estimates phytoplankton size class as percent microplankton (Sfm, > 20 μm). The calculation of Sfm requires satellite spectral remote sensing reflectance (Rrs(λ)), chlorophyll concentration ([Chl]), and absorption due to dissolved and detrital matter (adg(λ)). These are taken from 4km, monthly, Ocean Color Climate Change Initiative (OC-CCI, version 3.0, www.esa-oceancolour-cci.org) products which are globally merged Sea-Viewing Wide Field-of-View Sensor (SeaWiFS), Medium Resolution Imaging Spectrometer (MERIS), Moderate Resolution Imaging Spectroradiometer (MODIS-Aqua), and Visible Infrared Imaging Radiometer Suite (VIIRS) imagery for a continuous record from 1997 through 2015. This is an absorption-based approach from Mouw and Yoder (2010) (doi:10.1029/2010JC006337) where the chlorophyll-specific absorption spectra for phytoplankton size class extremes, pico- (0.2-2 μm) and microplankton (> 20 μm), are weighted by Sfm. Sfm is estimated from a look-up table containing simulated [Chl], adg(443), Rrs(λ), and Sfm. For a given pixel, satellite-estimated [Chl] and adg(443), are used to narrow the search space within the look-up table. Of the remaining options, the closest simulated Rrs(λ) to the satellite-observed Rrs(λ) is selected and the associated Sfm is assigned.