What should divers do if they encounter significantly reduced visibility during a night dive?

In situations where divers experience significantly reduced visibility during a night dive, signaling the dive buddy and evaluating the situation is crucial for ensuring safety. Reduced visibility can lead to potential hazards such as disorientation, loss of orientation relative to the dive site, or an increased risk of separation from the dive buddy. By communicating with the buddy, divers can assess whether it is safe to continue, determine if they should change depth, or even consider aborting the dive altogether. This collaborative approach helps maintain safety and awareness in an environment where visual references are limited.

The other options suggest actions that might compromise safety. Continuing the dive without concern could lead to dangerous situations due to unseen obstacles or increased risk of becoming lost. Starting a vertical ascent immediately might lead to decompression sickness if done improperly and without consideration of the dive's safety protocols. Ignoring the visibility issue and proceeding could result in loss of control over the dive situation and lead to accidents or injury. Therefore, engaging with the buddy and carefully assessing the situation is the most responsible and safest response.