1. In meteorology, an elongated area of relatively high atmospheric pressure, almost always associated with and most clearly identified as an area of maximum anticyclonic curvature of wind flow. The l
ocus of this maximum curvature is called the ridge line. Sometimes, particularly in discussions of atmospheric waves embedded in the westerlies, a ridge line is considered to be a line drawn through all points at which the anticyclonically curved isobars or contour lines are tangent to a latitude circle. The most common use of this term is to distinguish it from the closed circulation of a high (or anticyclone); but a ridge may include a high (and an upper-air ridge may be associated with a surface high) and a high may have one or more distinct ridges radiating from its center. The opposite of a ridge is a trough. (Sometimes called wedge.) 2. Also used as reference to other meteorological quantities such as equivalent potential temperature, temperature, and mixing ratio. That is, an elongated area of relatively high values of any particular field emanating from a maximum. 3. In oceanography, a linear accumulation of broken ice blocks projecting upward, formed by ice deformation, often at the edge of a floe. A ridge is distinguished from a hummock by being much longer than it is wide. The term ridge is often used to describe an entire ridged ice feature, in which case the portion above the water line is termed the sail and the portion below the water line is termed the keel.
A line or wall of broken ice forced up by pressure; it may be fresh or weathered. The submerged volume of broken ice under a ridge, forced downwards by pressure, is termed an ice keel.
A comparatively rectilinear conglomeration of ice fragments formed by pressure at the contact line between ice floes, usually along earlier existing cracks and leads or at the boundary between ice flo
es of different age. In this case, isostatically unbalanced hummocks usually form on the older ice surface. Ice ridges can also form as a result of direct fracturing of ice fields of thick and even first-year and multiyear ice at very strong pressures. The underwater portion of a ridge is termed an ice keel.
(1) An elongated area of relatively high atmospheric pressure; the opposite of trough. or (2) In hydrologic terms, a line or wall of broken ice forced up by pressure. May be fresh or weathered.
A ridge or wall of broken floating ice forced up by pressure. May be fresh or weathered. A corresponding ridge may also occur on the underside of the ice canopy and is called an ice keel.
Fractured ice piled in the form of several parallel ridges formed at the external boundary of fast ice or on drift divides as a result of repeated pressure.