Some of the largest scientific manipulation experiments conducted on our planet have enriched broad swaths of the surface ocean with iron. Surface ocean signatures of these iron enrichment experiments have covered areas up to > 1,000 km2 and have been conspicuous from space. Twelve of these multidisciplinary studies have been conducted since the early 1990s in three specific ocean regions—the Southern Ocean, and equatorial and sub-Arctic areas of the Pacific Ocean—where plant nutrients are perennially high (termed high nutrient low chlorophyll, or HNLC). In addition, a combined phosphorus and iron enrichment experiment was conducted in the oligotrophic North Atlantic Ocean. Together, these studies represent a unique set of physical, chemical, optical, biological, and ecological data. The richness of these data sets is captured in an open-access relational database at the Biological and Chemical Oceanography Data Management Office (BCO_DMO; http://osprey.bco-dmo.org/program.cfm?flag=viewp&id=10&sortby=program). It is a product of Working Group 131 (The Legacy of in situ Iron Enrichment: Data Compilation and Modeling; http://www.scor-int.org/Working_Groups/wg131.htm) of the Scientific Committee on Oceanic Research. The purpose of this article is to make the wider community aware of this resource. It also presents the merits and provides examples of the utility of this database for exploring emerging topics in oceanography, such as the links between ecosystem processes and biogeochemical cycles; the feasibility and many side effects of oceanic geoengineering; and how understanding the coupling among physical, chemical, and biological processes at the mesoscale can inform the emerging field of submesoscale biogeochemistry.

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