The circulation of Ego's atmosphere is essentially a gigantic heat-exchange system caused by the unequal heating of Ego's surface by Sen.
The temperature and rainfall are high throughout the year and vegetation flourishes. Ego has a tropical rainy climate in which the average temperature in the coldest month is no lower than 8º C ( 46º F ). The windware sides of the two mountains, Cusson and Arenna are rainy.
Their leeward sides are in a rain shadow and are relatively dry.
Sixty percent of Ego's surface in covered by water and 65 percent of this amount is made up of oceans. The composition of seawater is dominated by the presence of chlorine and sodium. Other elements include magnesium, sulfur, calcium, potassium and other trace minerals. Ego's oceans are rich in animal and plant life. Up to 80 per cent of Ego's fresh surface water comes from mountains.
photo from British Mountains Website
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