In a scenic coastal village, Marisol and Dakarai decide to spend their afternoon at the beach. As the sun sets, creating a beautiful orange hue across the sky, both friends, after a game of frisbee, decide to cool off in the water. Marisol, who is wearing a long dress, carefully wades into the water until it reaches her knees. Meanwhile, Dakarai, wearing shorts, goes in a bit deeper, and the water level comes up to his waist. After splashing around for a bit, they hear their friend Zephyr calling for them from the shore. How does each respond?

Both Marisol and Dakarai turn towards Zephyr's voice but face a predicament. From her position, Marisol notices a small rowboat between her and Zephyr, partially obscuring her view of the shore and particularly of Zephyr. On the other hand, Dakarai, who is a bit further in the water, cannot see Zephyr or the boat at all. Instead, he catches sight of a distant sailboat on the horizon. Complicating matters, the sun is beginning to dip below the horizon, casting a long shadow across the water, and with the tide slowly coming in, both friends must decide their next actions to communicate successfully with their friend on the shore. What does each person see, and how do their perceptions of the beach and its surroundings differ based on their positions in the water?
Given their positions in the water and the objects in their environment, Marisol and Dakarai will have different perspectives on their surroundings. Marisol, standing with the water at knee level, has her line of sight interrupted by the small rowboat. Her eyes are above the height of the boat, allowing her to see its top surface, though her view of the shore directly behind the boat is obstructed. She can see Zephyr's figure, but parts of Zephyr may be hidden from her view by the rowboat. Depending on the size of the boat and Zephyr's position, she might see Zephyr's head and shoulders or merely the top of their head. The long shadow cast by the setting sun affects the visibility of colors and details, meaning Marisol might not be able to discern Zephyr's facial expressions or exact movements.

In contrast, Dakarai, who is deeper in the water with the level reaching his waist, is in a position where his perspective is much lower. His eye level is nearly at the same height as the top of the rowboat's hull. Therefore, the rowboat completely blocks his view of the shore immediately behind it, including Zephyr. However, Dakarai's angle allows him to see the distant sailboat on the horizon that Marisol cannot, as her line of sight in that direction is blocked by the shore. The distant sailboat is visible to Dakarai because it is higher off the water's surface than the rowboat and far enough away that the curvature of the Earth does not yet impede his view.

As the tide comes in, both Marisol and Dakarai will experience an increase in water level. For Marisol, who is closer to shore, the change might be minor at first, continuing to wet her dress only slightly higher up her legs. However, if the tide comes in quickly or is particularly high, it may eventually reach a point where it could cover her dress up to her waist, similar to how the water already covers Dakarai. For Dakarai, the rising tide will mean that more of his torso would be submerged, possibly up to his chest or higher, depending on the water's rise and the depth gradient of the beach.
As both are looking towards Zephyr from different points and heights above the water, their visual information and consequent understanding of the beach's geography will influence how they respond to Zephyr. Marisol might wave an arm above the boat to attract Zephyr's attention, ensuring it's visible, while Dakarai might not even attempt to wave if he's aware that the boat is blocking Zephyr's view of him. Instead, Dakarai may choose to shout or even move to a position where no obstacles obstruct the line of sight before attempting to visually signal to Zephyr.