text: The GLODAPv1.1 climatology contains analysed fields of "present day" (1990s) dissolved inorganic carbon (DIC), alkalinity, carbon-14 (C), CFC-11 and CFC-12.  The fields consist of three-dimensional, objectively-analysed global grids at 1° horizontal resolution, interpolated onto 33 standardised vertical intervals from the surface (0 m) to the abyssal seafloor (5500 m).  In terms of temporal resolution, the relative scarcity of the source data mean that, unlike the World Ocean Atlas, averaged fields are only produced for the annual time-scale.  The GLODAP climatology is missing data in certain oceanic provinces including the Arctic Ocean, the Caribbean Sea, the Mediterranean Sea and Maritime Southeast Asia.
  Additionally, analysis has attempted to separate natural from anthropogenic DIC, to produce fields of pre-industrial (18th century) DIC and "present day" anthropogenic .  This separation allows estimation of the magnitude of the ocean sink for anthropogenic , and is important for studies of phenomena such as ocean acidification.  However, as anthropogenic DIC is chemically and physically identical to natural DIC, this separation is difficult.  GLODAP used a mathematical technique known as C* (C-star) to deconvolute anthropogenic from natural DIC (there are a number of alternative methods).  This uses information about ocean biogeochemistry and  surface disequilibrium together with other ocean tracers including carbon-14, CFC-11 and CFC-12 (which indicate water mass age) to try to separate out natural  from that added during the ongoing anthropogenic transient.  The technique is not straightforward and has associated errors, although it is gradually being refined to improve it.  Its findings are generally supported by independent predictions made by dynamic models.
  The GLODAPv2 climatology largely repeats the earlier format, but makes use of the large number of observations of the oceans carbon cycle made over the intervening period (2000–2013). The analysed "present-day" fields in the resulting dataset are normalised to year 2002. Anthropogenic carbon was estimated in GLODAPv2 using a "transit-time distribution" (TTD) method (an approach using a Greens function). In addition to updated fields of DIC (total and anthropogenic) and alkalinity, GLODAPv2 includes fields of seawater pH and calcium carbonate saturation state (Ω; omega). The latter is a non-dimensional number calculated by dividing the local carbonate ion concentration by the ambient saturation concentration for calcium carbonate (for the biomineral polymorphs calcite and aragonite), and relates to an oceanographic property, the carbonate compensation depth. Values of this below 1 indicate undersaturation, and potential dissolution, while values above 1 indicate supersaturation, and relative stability.