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**Standardisation**
* I/O variables converted into International System of Units (SI) (e.g., K)
* Docstrings standardised in their descriptions (e.g., inputs as float arrays) and references
* Variable names standardised across function declarations (i.e., t2m vs t2k vs t_k → now t2_k)
* Use of temperature converter functions
* Input variables are limited to those explicitly needed in the function formula (see e.g., ``calculate_normal_effective_temperature`` function)
**New Functions**
* ``scale_windspeed`` function to scale 10m wind speed to height h with h < 10m
* ``calculate_nonsaturation_vapour_pressure`` to calculate vapour pressure at a given relative humidity and air temperature
* ``calculate_wbgt_simple`` function renamed
* ``calculate_normal_effective_temperature`` function renamed
**Improvements**
* thermofeel library docstring lists computed variables in alphabetical order
* the cosine of the solar zenith angle now computed via the `earthkit-meteo <https://github.com/ecmwf/earthkit-meteo>`_ library
* ``calculate_bgt`` function is calculated via a 4x faster formula
* ``calculate_saturation_vapour_pressure_multiphase`` formulas replaced with those used in the IFS
* changeable threshold in ``approximate_dsrp`` function (set to 0.1 by default)
* invalidity outside input variables range specified in ``calculate_wind_chill`` function docstring
**Bug Fixes**
* fixed ``approximate_dsrp`` to avoid fdir being overwritten with dsrp when calculating MRT
* fixed ``calculate_wbgt_simple`` constant value and vapour pressure calculated from non-saturated formula
* fixed ``calculate_bgt`` wind speed at 1.1m in input
* fixed ``calculate_mrt_from_bgt`` wind speed at 1.1m in input
* fixed ``calculate_normal_effective_temperature`` wind speed at 1.2m in input
* fixed ``calculate_apparent_temperature`` wind speed at 10m in input; vapour pressure calculated from non-saturated formula
* fixed ``calculate_wind_chill`` wind speed in km/h and operation symbols in main formula
* fixed ``calculate_heat_index_simplified`` a wrong sign and missing constant value in hiarray; hi set to 2m air temperature when the latter is below 20°C
* fixed ``fahrenheit_to_kelvin`` converter function