A mid-ocean ridge or mid-oceanic ridge is an underwater mountain range, formed by plate tectonics. This uplifting of the ocean floor occurs when convection currents rise in the mantle beneath the ocea
nic crust and create magma where two tectonic plates meet at a divergent boundary. The mid-ocean ridges of the world are connected and form a single global mid-oceanic ridge system that is part of every ocean, making the mid-oceanic ridge system the longest mountain range in the world.
The average of the minimum altitude and maximum altitude of the glacier. The mid-range altitude is of interest in itself as a measure of the vertical location of the glacier, but has also been shown t
o be (to within the accuracy of measurements) an unbiased estimator of the Balanced-budget ELA. See glaciation level.
A warm, moist sea breeze from the south that sets in at midday in Provence, France, south of Mount Ventoux. In the Roussillon region the midday south wind (mitgjorn) is irregular and generally light,
and is dry after crossing the Pyrenees.