Extended Data Fig. 1: Sampling density of DIP, DIC, ALK and O2.
From: Biological carbon pump estimate based on multidecadal hydrographic data
a, DIP. b, DIC. c, ALK. d, O2. The observational data, downloaded from the GLODAPv2 (ref. 15), are binned to the OCIM grid. The colour denotes the fraction of the grid boxes in each water column with at least one measurement. For each vertical column, the sampling density is defined as the number of grid boxes with at least one sample divided by the total number of wet grid boxes.
