Table S2.

Sources and values of different constraining data streams used in the optimization

  • The blue and orange shading indicates the length of time covered. The constraining data tiers were defined as follows: tier 1, direct carbon observations (e.g., CGR); tier 2, indirect carbon observations unambiguously related to carbon quantities (e.g., O2/N2); tier 3, direct carbon observations with an empirical (data-driven) model used to obtain global estimates, for example, the use of geostatistics to up-scale local data into global values; tier 4, indirect carbon observations not simply related to global carbon flux quantities.