The quickest way â€“ not shortest distance â€“ between two points
Sound waves through an aluminum tube; standing waves in liquids
Swamps, Marshes, Ocean inletsâ€¦All of these are wetlands, which have standing water and are not deep
Hydro periods are a fingerprint on how wetlands receive their water: from river overflows, rain, or runoff. To understand a particular wetland, scientists must understand where the water comes from, and to figure out if a wetland is OPEN or CLOSED.