WeatheringWeathering is the deterioration of rocks, soils and minerals (as well as wood and artificial materials) through contact with water, atmospheric gases, sunlight, and biological organisms. It occurs in situ (on-site, with little or no movement), and so is distinct from erosion, which involves the transport of rocks and minerals by agents such as water, ice, snow, wind, waves and gravity. Weathering processes are either physical or chemical.
Ice lensIce lenses are bodies of ice formed when moisture, diffused within soil or rock, accumulates in a localized zone. The ice initially accumulates within small collocated pores or pre-existing crack, and, as long as the conditions remain favorable, continues to collect in the ice layer or ice lens, wedging the soil or rock apart. Ice lenses grow parallel to the surface and several centimeters to several decimeters (inches to feet) deep in the soil or rock.
Frost heavingFrost heaving (or a frost heave) is an upwards swelling of soil during freezing conditions caused by an increasing presence of ice as it grows towards the surface, upwards from the depth in the soil where freezing temperatures have penetrated into the soil (the freezing front or freezing boundary). Ice growth requires a water supply that delivers water to the freezing front via capillary action in certain soils.
FreezingFreezing is a phase transition in which a liquid turns into a solid when its temperature is lowered below its freezing point. For most substances, the melting and freezing points are the same temperature; however, certain substances possess differing solid-liquid transition temperatures. For example, agar displays a hysteresis in its melting point and freezing point. It melts at 85 °C (185 °F) and solidifies from 32 to 40 °C (90 to 104 °F).
IceFrozen water; the solid state of waterIce is water that is frozen into a solid state, typically forming at or below temperatures of 0 °C, 32 °F, or 273.15 K. It occurs naturally on Earth, on other planets, in Oort cloud objects, and as interstellar ice. As a naturally occurring crystalline inorganic solid with an ordered structure, ice is considered to be a mineral.
Capillary actionAbility of a liquid to flow in narrow spaces Capillary water flow up a 225 mm-high porous brick after it was placed in a shallow tray of water. The time elapsed after first contact with water is indicated. From the weight increase, the estimated porosity is 25%.
Alpine climateAlpine climate is the typical climate for elevations above the tree line, where trees fail to grow due to cold. This climate is also referred to as a mountain climate or highland climate. DefinitionThere are multiple definitions of alpine climate. In the Köppen climate classification, the alpine and mountain climates are part of group E, along with the polar climate, where no month has a mean temperature higher than 10 °C (50 °F).
Stress (mechanics)Physical quantity that expresses internal forces in a continuous material StressResidual stresses inside a plastic protractor are revealed by polarized light.Common symbolsσSI unitpascalOther unitspsi, barIn SI base unitsPa = kg⋅m−1⋅s−2Dimension L − 1 M T − 2 {\displaystyle {\mathsf {L}}^{-1}{\mathsf {M}}{\mathsf {T}}^{-2}} In continuum mechanics, stress is a physical quantity that describes forces present during deformation.Polar climateThe polar climate regions are characterized by a lack of warm summers but with varying winters. Every month a polar climate has an average temperature of less than 10 °C (50 °F). Regions with a polar climate cover more than 20% of the Earth's area. Most of these regions are far from the equator and near the poles, and in this case, winter days are extremely short and summer days are extremely long. They could last for the entirety of each season or longer.
AltitudeAltitude is a distance measurement, usually in the vertical or "up" direction, between a reference datum and a point or object. The exact definition and reference datum varies according to the context (e.g., aviation, geometry, geographical survey, sport, or atmospheric pressure). Although the term altitude is commonly used to mean the height above sea level of a location, in geography the term elevation is often preferred for this usage.
BoulderIn geology, a boulder is a rock fragment with size greater than 25.6 cm (10.1 in) in diameter. Smaller pieces are called cobbles and pebbles. While a boulder may be small enough to move or roll manually, others are extremely massive. In common usage, a boulder is too large for a person to move. Smaller boulders are usually just called rocks or stones. EtymologyThe word boulder derives from boulder stone, from Middle Englishbulderston or Swedishbullersten.
Subarctic climateClimate characterised by long, usually very cold winters, and short, cool summersSubarctic climate worldwide as of 1991-2020, using the −3 °C (27 °F) threshold for the coldest month. The subarctic climate (also called subpolar climate, or boreal climate) is a continental climate with long, cold (often very cold) winters, and short, warm to cool summers.
PeriglaciationPeriglaciation (adjective: "periglacial", referring to places at the edges of glacial areas) describes geomorphic processes that result from seasonal thawing and freezing, very often in areas of permafrost. The meltwater may refreeze in ice wedges and other structures. "Periglacial" originally suggested an environment located on the margin of past glaciers. However, freeze and thaw cycles influence landscapes also outside areas of past glaciation.*As an Amazon Associate I earn from qualifying purchases.