Phytoplankton data from the cruise number M103-1 with research vessel "Meteor" from 27.12.2013 to 18.1.2014 (from Walvis Bay to Walvis Bay) in front of Namibia. Phytoplankton samples taken by CTD- rosette sampler from different depths. If “Depth top” and “Depth bot” show the same number, the sample was taken from that depth. If numbers of “Depth top” and “Depth bot” differ, they indicate the range of depths where several samples were taken and joined to an integrated sample (procedure cf. HELCOM 2010). The average depth of such integrated sample is given in column ”Depth water [m]”.Phytoplankton counted by means of inverted microscope according to the classical UTERMÖHL method. Counts converted to biomass (wet weight) according to the method described by HELCOM (2010, http://www.helcom.fi/groups/monas/CombineManual/AnnexesC/en_GB/). Principle of the method also described by Olenina et al. (2006, hdl:10013/epic.39031.d001).