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How can tidal locking affect conditions on a planet orbiting a faint dwarf star?

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Habitable zone The habitable zones (green) for stars that are like the Sun (middle), hotter than the Sun (top), and cooler than the Sun (bottom). The red areas are those in which liquid surface water would be lost as a result of a runaway greenhouse effect, and the blue areas are those in which liquid surface water would be completely frozen.

Tidal locking occurs when the gravitational interaction between a planet and its host star causes the planet's rotational period to synchronize with its orbital period. For a planet orbiting a faint dwarf star, this process typically results in one hemisphere being permanently illuminated (perpetual day) while the other remains in darkness (perpetual night).12

This state significantly impacts the planet's climate and potential habitability:

Temperature Extremes: Without rotation to distribute heat, the day side may experience intense, constant heating, while the night side risks freezing temperatures.2
Atmospheric Redistribution: The habitability of such a world often depends on its atmosphere. If the planet possesses a sufficiently thick atmosphere—potentially containing greenhouse gases like carbon dioxide—heat can be transported from the day side to the night side, preventing the atmosphere from freezing out on the dark side and potentially maintaining conditions suitable for liquid water.2

While tidal locking creates a challenging environment, it does not automatically preclude the existence of a habitable zone if the planet's atmospheric properties can effectively mitigate these extreme temperature gradients.2