In what part of the coastal environment must organisms develop strategies to deal with exposure to the atmosphere two times a day?

Middle intertidal zones

Explanation:

Middle intertidal zones are zones within the intertidal regions of coastal environment which are submerged by water for large period of time but exposed to the atmosphere twice per day, during the periods of low tides.

Biodiversity within the middle intertidal zones are primarily adapted for underwater conditions, but must find ways to cope with exposure to atmosphere during the low tide periods. The zone serves as habitats for a relatively large variety of plants and animals.

Other zones within the intertidal regions include:

High intertidal zones Spray zones Low intertidal zones