spyice.misc_subroutines#

This module provides functions to calculate the melting temperature of seawater based on salinity. It supports different liquidus relations such as “Normal” and “Frezchem”.

Functions#

calculate_melting_temperature_from_salinity#

calculate_melting_temperature_from_salinity(_salinity, _temperature_melt=_temperature_melt, _liquid_relation='Normal')#

Calculates the melting temperature of seawater based on salinity.

Parameters:

  • _salinity (numpy.ndarray) – Array of salinity values (in ppt).

  • _temperature_melt (float) – Reference melting temperature (solidus) in Kelvin. Defaults to the UserInput value.

  • _liquid_relation (str) – Type of liquidus relation. Must be either “Normal” or “Frezchem”. Defaults to “Normal”.

Returns:

numpy.ndarray of melting temperatures corresponding to the input salinity values.

Raises:

TypeError – If _liquid_relation is not “Normal” or “Frezchem”.

Description:

  • Normal relation: Uses a linear interpolation between the solidus temperature and the eutectic temperature. Eutectic temperature T_s = 252.05 K, brine salinity S_br = 233 ppt.

    For scalar salinity:

    \[T_{melt} = T_m + (T_s - T_m) * \frac{S}{S_{br}}\]

    For array salinity, the same formula is applied element-wise.

  • Frezchem relation: Uses a quadratic fit from the Frezchem database:

    \[T_{melt} = 272.63617665 - 9.1969758 \times 10^{-5} S^2 - 0.03942059 S\]