Final answer:
Alternate weather minima requirements for aerodromes depend on the availability of a navigational aid, which assists pilots in landing safely in poor weather conditions.
Step-by-step explanation:
Alternate weather minima requirements are predicated upon the aerodrome having a navigational aid available. This means that pilots need to have access to certain navigational systems at the alternate airport that can assist them in landing the aircraft safely, especially in poor weather conditions. Such systems may include Instrument Landing Systems (ILS), Non-Directional Beacons (NDB), or Distance Measuring Equipment (DME). Minimum weather conditions, such as visibility and ceiling, may be higher if no navigational aids are available at the alternate aerodrome.