The GOA-ON Data Explorer provides access and visualization to ocean acidification data and data synthesis products being collected around the world from a wide range of sources, including moorings, research cruises, and fixed time series stations. Layers contain contoured world-wide data; Platforms include icons for various observing assets, some of which display real-time data and many of which include links to data and metadata. For a given asset measuring carbonate chemistry, metadata includes information on which parameters are measured, links to data providers, and other useful details. The inventory of GOA-ON assets can be searched interactively by region, platform type, and variables by using the Filters tool.