Due to refraction, how do objects appear underwater when viewed through a mask?

Objects appear larger and closer underwater due to the phenomenon of refraction. When light passes from water into air, it bends (or refracts) as it moves between these two different mediums. This bending of light creates the illusion that objects are closer than they actually are and makes them appear larger. For this reason, divers observe marine life and underwater structures differently than they do at the surface or in air.

The distortion caused by light bending can result in an altered perception of size and distance. It's essential for divers to understand this visual effect, as it influences how they interact with their environment and assess distances and sizes while underwater. This understanding is crucial for navigation, monitoring air supply, and making safe diving decisions.