MaxPower RPMs ~ Home of the Ice Cube Cylinder and Replating as well as Race Winning Technologies For 2/4 Stroke Engines And Big Bore Performance inlcuding Wiseco. The Importance of the Tropical Hot Spot to EPA’s Endangerment Finding. See more on this by former EPA economist and Science analyst here and here. The daily Sea Ice Index provides a quick look at Arctic-wide changes in sea ice. It provides consistently processed daily ice extent and concentration images and data. A Yakhchal in Kerman is located about one and a half kilometres from the centre of the city. This cone-shaped building is about eighteen metres high. NOAA National Weather Service Buffalo, NY. Potent Winter Storm Impacting the Upper MIssissippi Valley. An arctic blast from Canada will enhance snowfall across the.The #1 source for the hottest hip-hop songs 2016, mixtapes, videos & news, updated daily!! Download and stream music for free on HotNewHipHop! USGS: Volcano Hazards Program - USGS: Volcano Hazards Program Glossary. New ice-age blog - www.iceagenow.info Many, many readers have asked me to create a blog so that they can leave comments, so here it is: www.iceagenow.info This. Ice was originally thought to be slippery due to the pressure of an object coming into contact with the ice, melting a thin layer of the ice and allowing the object. As an information and referral center in support of polar and cryospheric research, NSIDC archives and distributes digital and analog snow, ice, and glaciological data. Ghirardelli Chocolate - Chocolate Gifts, Bars and Recipes. Perfectly- sized to sit atop a graham cracker, our SQUARES come in a variety of flavors that make savoring this fireside snack even more fun! Ice - Wikipedia. This article is about water ice. For the broader concept of . For other uses, see Ice (disambiguation). The white zone in the center is the result of tiny air bubbles. Ice is waterfrozen into a solid state. Depending on the presence of impurities such as particles of soil or bubbles of air, it can appear transparent or a more or less opaque bluish- white color. In the Solar System, ice is abundant and occurs naturally from as close to the Sun as Mercury to as far as away the Oort cloud objects. Beyond the Solar System, it occurs as interstellar ice. It is abundant on Earth's surface . It falls as snowflakes and hail or occurs as frost, icicles or ice spikes. Ice molecules can exhibit up to sixteen different phases (packing geometries) that depend on temperature and pressure. When water is cooled rapidly (quenching), up to three different types of amorphous ice can form depending on the history of its pressure and temperature. When cooled slowly correlated proton tunneling occurs below 2. K giving rise to macroscopic quantum phenomena. Virtually all the ice on Earth's surface and in its atmosphere is of a hexagonalcrystalline structure denoted as ice Ih (spoken as . The most common phase transition to ice Ih occurs when liquid water is cooled below 0. It may also be deposited directly by water vapor, as happens in the formation of frost. The transition from ice to water is melting and from ice directly to water vapor is sublimation. Ice is used in a variety of ways, including cooling, winter sports and ice sculpture. Characteristics. The three- dimensional crystal structure of H2. O ice Ih (c) is composed of bases of H2. O ice molecules (b) located on lattice points within the two- dimensional hexagonal space lattice (a). The white box in (c) is the unit cell defined by Bernal and Fowler. However, many of the physical properties of water and ice are controlled by the formation of hydrogen bonds between adjacent oxygen and hydrogen atoms; while it is a weak bond, it is nonetheless critical in controlling the structure of both water and ice. An unusual property of ice frozen at atmospheric pressure is that the solid is approximately 8. The density of ice is 0. Liquid water is densest, essentially 1. This is due to hydrogen bonding dominating the intermolecular forces, which results in a packing of molecules less compact in the solid. Density of ice increases slightly with decreasing temperature and has a value of 0. It is also a common cause of the flooding of houses when water pipes burst due to the pressure of expanding water when it freezes. The result of this process is that ice (in its most common form) floats on liquid water, which is an important feature in Earth's biosphere. It has been argued that without this property, natural bodies of water would freeze, in some cases permanently, from the bottom up. Sufficiently thin ice sheets allow light to pass through while protecting the underside from short- term weather extremes such as wind chill. This creates a sheltered environment for bacterial and algal colonies. When sea water freezes, the ice is riddled with brine- filled channels which sustain sympagic organisms such as bacteria, algae, copepods and annelids, which in turn provide food for animals such as krill and specialised fish like the bald notothen, fed upon in turn by larger animals such as emperor penguins and minke whales. During the melting process, the temperature remains constant at 0 . While melting, any energy added breaks the hydrogen bonds between ice (water) molecules. Energy becomes available to increase the thermal energy (temperature) only after enough hydrogen bonds are broken that the ice can be considered liquid water. The amount of energy consumed in breaking hydrogen bonds in the transition from ice to water is known as the heat of fusion. As with water, ice absorbs light at the red end of the spectrum preferentially as the result of an overtone of an oxygen. Compared with water, this absorption is shifted toward slightly lower energies. Thus, ice appears blue, with a slightly greener tint than for liquid water. Since absorption is cumulative, the color effect intensifies with increasing thickness or if internal reflections cause the light to take a longer path through the ice. For instance, icebergs containing impurities (e. This explanation, called . It, however, did not account for skating on ice temperatures lower than . These molecules remain in a semi- liquid state, providing lubrication regardless of pressure against the ice exerted by any object. However, the significance of this hypothesis is disputed by experiments showing a high coefficient of friction for ice using atomic force microscopy. However, this theory does not sufficiently explain why ice is slippery when standing still even at below- zero temperatures. In typical conditions related to winter sports and tires of a vehicle on ice, melting of a thin ice layer due to the frictional heating is the primary reason for the slipperiness. Natural formation. Feather ice on the plateau near Alta, Norway. The crystals form at temperatures below . Ice is an important component of the global climate, particularly in regard to the water cycle. Glaciers and snowpacks are an important storage mechanism for fresh water; over time, they may sublimate or melt. Snowmelt is an important source of seasonal fresh water. The World Meteorological Organization defines several kinds of ice depending on origin, size, shape, influence and so on. Ice which calves (breaks off) from an ice shelf or glacier may become an ice berg. Sea ice can be forced together by currents and winds to form pressure ridges up to 1. Navigation through areas of sea ice occurs in openings called . Ice, frozen in the stream bed, blocks normal groundwater discharge, and causes the local water table to rise, resulting in water discharge on top of the frozen layer. This water then freezes, causing the water table to rise further and repeat the cycle. The result is a stratified ice deposit, often several meters thick. Freezing rain is a type of winter storm called an ice storm where rain falls and then freezes producing a glaze of ice. Ice can also form icicles, similar to stalactites in appearance, or stalagmite- like forms as water drips and re- freezes. The term . On structures, an ice dam is the buildup of ice on a sloped roof which stops melt water from draining properly and can cause damage from water leaks in buildings. On rivers and streams. Ice which forms on moving water tends to be less uniform and stable than ice which forms on calm water. Ice jams (sometimes called . Ice jams can cause flooding, damage structures in or near the river, and damage vessels on the river. Ice jams can cause some hydropower industrial facilities to completely shut down. An ice dam is a blockage from the movement of a glacier which may produce a proglacial lake. Heavy ice flows in rivers can also damage vessels and require the use of an icebreaker to keep navigation possible. Ice discs are circular formations of ice surrounded by water in a river. Pancake ice is a formation of ice generally created in areas with less calm conditions. On lakes. Ice forms on calm water from the shores, a thin layer spreading across the surface, and then downward. Ice on lakes is generally four types: Primary, secondary, superimposed and agglomerate. Secondary ice forms below the primary ice in a direction parallel to the direction of the heat flow. Superimposed ice forms on top of the ice surface from rain or water which seeps up through cracks in the ice which often settles when loaded with snow. Shelf ice occurs when floating pieces of ice are driven by the wind piling up on the windward shore. Candle ice is a form of rotten ice that develops in columns perpendicular to the surface of a lake. In the air. Ice formation on vehicle windshield. Rime ice. Rime is a type of ice formed on cold objects when drops of water crystallize on them. This can be observed in foggy weather, when the temperature drops during the night. Soft rime contains a high proportion of trapped air, making it appear white rather than transparent, and giving it a density about one quarter of that of pure ice. Hard rime is comparatively dense. Ice pellets. An accumulation of ice pellets. Ice pellets are a form of precipitation consisting of small, translucent balls of ice. This form of precipitation is also referred to as . Ice pellets are usually smaller than hailstones. The METAR code for ice pellets is PL. This causes the partial or complete melting of any snowflakes falling through the warm layer. As they fall back into the sub- freezing layer closer to the surface, they re- freeze into ice pellets. However, if the sub- freezing layer beneath the warm layer is too small, the precipitation will not have time to re- freeze, and freezing rain will be the result at the surface. A temperature profile showing a warm layer above the ground is most likely to be found in advance of a warm front during the cold season. The storm's updraft blows the hailstones to the upper part of the cloud. The updraft dissipates and the hailstones fall down, back into the updraft, and are lifted up again. Hail has a diameter of 5 millimetres (0. The hailstone then may undergo 'wet growth', where the liquid outer shell collects other smaller hailstones. Once a hailstone becomes too heavy to be supported by the storm's updraft, it falls from the cloud. For this reason, hail is most common within continental interiors of the mid- latitudes, as hail formation is considerably more likely when the freezing level is below the altitude of 1. Accordingly, hail is actually less common in the tropics despite a much higher frequency of thunderstorms than in the mid- latitudes because the atmosphere over the tropics tends to be warmer over a much greater depth. Hail in the tropics occurs mainly at higher elevations. These droplets are able to remain liquid at temperatures lower than .
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