Islands and coastal areas 10° to 20° north or south of the equator usually have a tropical marine climate. The climate of the tropical marine system is influenced by the sea. There are two main seasons the wet season and the dry season. The annual rainfall is 1000 to over 1500mm. The temperature ranges from 27°C to 30°C. The trade winds blow all year round. The trade winds are moist as they have past over warm seas.
The wet season of the tropical marine climate occurs during the period when the conditions of the atmosphere are not stable. At this time, the regions (10° to 20° north or south of the equator) experience tropical disturbances. Around this time islands like Greneda are affected by the ITCZ (Intertropical Convergence Zone). The most rainfall comes during between July to September.
The ecosystems of the tropical marine climate have to adapt to the dry season. Plants during the dry season must conserve water/moisture. However the extent of the adaptation depends much on the annual rainfall. Hygrophytic ecosystems occur when there is a short dry period with a few rain showers. The soil in this ecosystem holds adequate water for plant growth. The most of the tropical marine ecosystems are close to true rainforests.
The mesophytic ecosystem is also know an as a semi-evergreen forest. It is found where there is a long dry season that has little rainfall. There is less vegetation than in a rainforest and the layer structure is simpler. There are only 2 tree stories, trees shed their leaves or have very small leaves. This provides the plants a way to conserve moisture. There is fewer epiphytes than a rain forest has as the canopy is dry. In the dry season the ground is covered by leaves that will not decay until the soil is moist. The trees often flower during the dry season and start to grow during the wet season. The soil is usually latasol.