Gibbs himself considered the following problem that arises if the ideal gas entropy is not extensive. Two identical containers of an ideal gas sit side-by-side. There is a certain amount of entropy S associated with each container of gas, and this depends on the volume of each container.
The intertidal zone is the area of the ocean between the high tide and low tide lines, usually on the beach at the water's edge. If you think of the line created at high tide as the upper limit and the line created at low tide as the lower limit, the intertidal zone is everything between those lines.
The area can be a narrow strip, as in Pacific islands that have only a narrow tidal range, or can include many meters of shoreline where shallow beach slopes interact with high tidal excursion. Organisms in the intertidal zone are adapted to an environment of harsh extremes. Water is available regularly with the tides but varies from fresh with rain to highly saline and dry salt with drying between tidal inundations. The action of waves can dislodge residents from the littoral zone.