The summit is famous in weather circles for its rime ice accumulations, which come from tiny supercooled water droplets in clouds that freeze on contact with a surface.
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Douglas Ciampi of Westminster, Massachusetts, stands next to a rime ice-covered antenna while taking in the view from the summit of Mount Washington, New Hampshire, Feb. 23.
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A particular feature of the local climate is the instantly freezing rain, covering the northeast-facing surfaces with layers of rime ice. There is little snow in winter, with the island remaining icebound for several months, the ice forms varying from solid firn, through glazed surfaces, to rime ice. Even though Kulusuk lies approximately south of the Arctic Circle, the celestial phenomenon of Aurora borealis can still be observed in the village.
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Wilson Bentley micrograph showing two classes of snow crystals, plate and column. Snow crystal with a column capped with plates, which are growing rime ice. Precipitation may be characterized by type and intensity.
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Rime ice is formed when wind-driven droplets of water collide and freeze on an object like a tree branch on the trail. Hiking in the winter and in the spring are completely different experiences.
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The peak is the highest of a four mountain chain: the other peaks are Torre Egger (), Punta Herron, and Cerro Standhardt. The top of the mountain often has a mushroom of rime ice, formed by the constant strong winds, increasing the difficulty of reaching the actual summit.
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Additionally, the tube is heated to prevent rime ice formation on the tube. There are two lines from the tube down to the devices to measure the difference in pressure of the two lines. The measurement devices can be manometers, pressure transducers, or analog chart recorders.
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The mountain has limited forest due to the harsh weather during the wintertime. Normal conditions like frost, sleet, hail, snow, and freezing rain can cause the limbs on trees to snap. Higher up on the mountain, frost flowers, ice crystals, hoarfrost, rime ice, and freezing fog can occur.
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A change in opacity registers as rime ice. A change in refractive index registers as clear ice. Optical components are made of acrylic, which is the material used for aircraft windshields. The wavelength of the transducer's excitation light is not visible to the human eye so as not to be mistaken for any kind of navigational running light.
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As the formation progress, the aboveboard weight of the vessel increases and may ultimately cause capsizing. Furthermore, rime ice may impede the correct functioning of important navigational instruments on board, such as radar or radio installations. Different strategies for the removal of such ice are employed: chipping away the ice or even using fire hoses in an attempt to remove the ice.
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The closely related mountain laurel blooms in between the two, and all of the blooms progress from lower to higher elevations. The reverse is true in autumn, when nearly bare mountaintops covered in rime ice (frozen fog) can be separated from green valleys by very bright and varied leaf colors. The rhododendrons are broadleafs, whose leaves droop in order to shed wet and heavy snows that come through the region during winter.
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Rime is a milky white accumulation of super-cooled cloud or fog droplets that freeze when they strike an object that has a temperature of , the freezing point of water. The process is called riming when super-cooled cloud droplets attach to ice crystals in the formation of graupel. Rime ice can pose a hazard to an airliner when it forms on a wing as an aircraft flies through a cloud of super-cooled droplets.
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The McAfee Knob trail is most popular in the spring and fall seasons, and there has been an average of around 100 hikers on the trail at once. When hiking the trail in the winter, there will most likely be no one else there. Among other things to encounter are the spikes of frost from the icy moisture that form on objects such as rocks, leaves and frozen soil. The terms used to describe these coverings are "rime ice" and "hoarfrost".
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Electron microscope image of rime ice on both ends of a "capped column" snowflake Under some atmospheric conditions, forming and descending snow crystals may encounter and pass through atmospheric supercooled cloud droplets. These droplets, which have a diameter of about , can exist in the unfrozen state down to temperatures near . Contact between the snow crystal and the supercooled droplets results in freezing of the liquid droplets onto the surface of the crystals. This process of crystal growth is known as accretion.
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Due to high elevation, frequently located at cloud level, spectacular rime ice is frequently seen totally coating the forest in pure white. Despite the overall vigorous winter, the relative southern location (39th North parallel) allows for occasional intrusions of warmer, well above freezing air from the Gulf of Mexico. Thus, rain can occur during even the coldest winter months. During one of the snowiest winters in history (2009–10), about 275 inches (700 cm) of snow is estimated to have fallen above 4,000 feet (1,220 m).
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The mountains in this area, particularly the Cheat and Back Allegheny, are notorious for their bad weather, especially in winter. Both record lows and record snowfall for the state of West Virginia have occurred here. Terrible storms and bitter cold are the norm from November to April, although it has been known to snow on the highest summits as early as mid-September and as late as June 7. Freezing temperatures and frost have occurred during every month and rime ice accumulations are common above .
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Mudplaning is the loss of traction of a wheel when the pavement is covered by a very thin layer of sand and waste oils. It may occur during the first rainfall (or through other means of dampening) on a specific area which has been dry for a period of time. When the rain first falls down, the thin layer of dust mixes with waste oils and turns into a nearly transparent layer of grease. The color of asphalt remains as usual while the underlying mixture may still cause a critical loss of traction comparable to that of driving on rime ice.
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The latter's leaves are rougher and ice less than the smoother lotus. Aircraft icing accidents result from a combination of increased weight, increased drag, decrease or loss of lift, and decrease or loss of thrust from ice accumulation on the airframe, airfoil(s), propellers (if present) and or wings, depending on the type of ice that forms (e.g. rime ice, clear ice, etc.), which is a function of the specific meteorological conditions. Also, induction ice can cause power losses in icing conditions either externally at air intakes (either turbine or piston aircraft), or locally in the induction system within the engine (e.g.
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October is especially dramatic, as the colored leaves stand out boldly and occur mostly at the same time, unlike the flowers. Major trees include oak, hickory, and tulip tree at lower elevations and buckeye and ash in the middle, turning into conifers such as fir and spruce at the highest elevations on the parkway. Trees near ridges, peaks, and passes (often called gaps or notches) are often distorted and even contorted by the wind, and persistent rime ice is deposited by passing clouds in the winter. The Blue Ridge Parkway has also been a corridor for the spread of many invasive species, including oriental bittersweet, privet, and multiflora rose.
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North-looking oblique aerial photograph showing a small, unnamed hanging glacier located in the Chugach Mountains, near Cordova Peak, Chugach National Forest, Alaska. Glacier ice accumulation occurs through accumulation of snow and other frozen precipitation, as well as through other means including rime ice (freezing of water vapor on the glacier surface), avalanching from hanging glaciers on cliffs and mountainsides above, and re-freezing of glacier meltwater as superimposed ice. Accumulation is one element in the glacier mass balance formula, with ablation counteracting. With successive years in which accumulation exceeds ablation, then a glacier will experience positive mass balance, and its terminus will advance.
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Wind speeds exceeding 100 km/h occur throughout the year, often causing flight cancellations at the Kulusuk Airport. Neighboring Tasiilaq−where the main local weather station is located−holds the settlement windspeed record for Greenland: on 7 February 1970 the speed peaked at or Moraine boulders under Qalorujoorneq: rime ice windblasted on the northeast-facing surfaces Pack ice and small icebergs pushed forth by the East Greenland Current ram against the northeastern coast, blocking the Ikaasaartik Sound and facilitating the freeze of the wider Torsuut Tunoq waterway. Aurora borealis over Kulusuk Conversely, when the Greenland High pressure area from the Greenland ice sheet () moves towards the area in winter, Kulusuk can be as wind-free and sunny as the inner parts of the Uummannaq Fjord region known as the sunniest spot in Greenland. Kulusuk experiences one of the windiest winters, with rougher weather than the rest of Greenland.
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With testing completed to simulate high-altitude conditions, the GE9X should be free of ice crystal icing (core icing) which was an issue for the GEnx. This is now better understood as well as traditional rime ice. The improvements developed for the GEnx were the variable bypass valve doors: airflow is improved by the way they open inward into the flow path between the booster and high-pressure compressor, naturally ejecting the ice and sand to prevent them from entering the core. Minor tweaks between FETT and second engine to test (SETT) are pivotal to hit its efficiency goals: in the throat between the HP turbine outlet into the LP turbine inlet, the turbine's pinch point is altered to set the operating line of the compressor, turbine and fan. Blades at the back end of the 11-stage HP compressor are just over high. The HP compressor front end tip clearance was modified as the compressor was fine-tuned since initial tests in early 2013.
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