Size-fractionated iron measurements from surface sampling and depth profiles along 22N in the North Atlantic during summer 2017 on cruise JC150.

The distribution of size-fractionated iron in the subtropical North Atlantic was investigated along a meridional transect at 22deg N in summer 2017 to gain insights into the biogeochemical cycling of the different size classes of iron in the ocean. Samples for soluble, dissolved and total dissolvable were taken from onboard the R.R.S. James Cook (Cruise JC150) from the underway sampling system at 130 locations as well as well from full-depth CTD casts at seven stations. Iron concentrations were measured by flow injection analysis with chemiluminescence detection onboard and at the University of Southampton.