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Adjust conditions

To adjust the system to a different set of temperature and/or pressure conditions, use adjust:

co2s_adj = co2s.adjust(
    temperature=25,
    pressure=1000,
    store_steps=1,
    method_fCO2=1,
    opt_which_fCO2_insitu=1,
    bh_upsilon=None,
)

The result co2s_adj is a new CO2System with all values at the new conditions (above, temperature of 25 °C and hydrostatic pressure of 1000 dbar).

For more on the store_steps kwarg, see Advanced results access.

The adjust method can be used if any two carbonate system parameters are known, but also if only one of pCO2, fCO2, [CO2(aq)] or xCO2 is known. In this case, adjust can take additional kwargs:

  • method_fCO2: how to do the temperature conversion.

    • 1: using the parameterised υh equation of H24 (default).
    • 2: using the constant υh fitted to the TOG93 dataset by H24.
    • 3: using the constant theoretical υx of H24.
    • 4: following the H24 approach but using a user-provided b_h value (given with the additional kwarg bh_upsilon).
    • 5: using the linear fit of TOG93.
    • 6: using the quadratic fit of TOG93 (default before v1.8.3).

  • opt_which_fCO2_insitu: whether the input (1, default) or output (2) condition pCO2, fCO2, [CO2(aq)] and/or xCO2 values are at in situ conditions, for determining b_h with the parameterisation of H24. Only applies when method_fCO2 is 1.

  • bh_upsilon: If this is a single-parameter system and method_fCO2 is 4, then the value of b_h in J/mol must be specified here.