The reason is that darknessâor, to put it the other way, the absence of lightâstimulates the production of a hormone, melatonin, from its immediate precursor, the neurotransmitter serotonin. Like serotonin, melatonin plays important roles in our physical and mental well-being.
The five major ocean gyres. A gyre in oceanography is any large system of circulating ocean currents, particularly those involved with large wind movements. Gyres are caused by the Coriolis effect; planetary vorticity along with horizontal and vertical friction, determine the circulation patterns from the wind curl (torque).
See also troposphere, stratosphere, mesosphere, ionosphere. 2. the air or climate in a particular place: the atmosphere was thick with smoke. 3. a general pervasive feeling or mood: an atmosphere of elation. 4. (Art Terms) the prevailing tone or mood of a novel, symphony, painting, or other work of art. 5. a special mood or character associated with a place. 6. (Chemistry) any local gaseous environment or medium: an inert atmosphere.