Which predive observation can assist with natural navigation during a dive?

Time of day and sun direction is a critical predive observation for natural navigation underwater. The position of the sun in relation to the time of day can help divers orient themselves. For example, knowing that the sun rises in the east and sets in the west allows divers to determine cardinal directions. This is essential when navigating underwater where visibility may be limited.

The angle of sunlight filtering through the water can also provide visual cues about the surrounding environment, such as the depth or proximity to the surface. Using the sun as a navigational tool is particularly useful in open water where there are fewer landmarks or defining features to guide you.

In contrast, other observations like the boat's depth finder provide information about depth but do not assist in navigation. Underwater flora can indicate specific habitats and may help identify locations, but it is not a reliable method for determining direction. Current speed is important for understanding drift and planning return routes, but it does not aid in identifying navigational points or direction.