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Topic Review
List of Selected Stars for Navigation
Fifty-eight selected navigational stars are given a special status in the field of celestial navigation. Of the approximately 6,000 stars visible to the naked eye under optimal conditions, the selected stars are among the brightest and span 38 constellations of the celestial sphere from the declination of −70° to +89°. Many of the selected stars were named in antiquity by the Babylonians, Greeks, Romans, and Arabs. The star Polaris, often called the "North Star", is treated specially due to its proximity to the north celestial pole. When navigating in the Northern Hemisphere, special techniques can be used with Polaris to determine latitude or gyrocompass error. The other 57 selected stars have daily positions given in nautical almanacs, aiding the navigator in efficiently performing observations on them. A second group of 115 "tabulated stars" can also be used for celestial navigation, but are often less familiar to the navigator and require extra calculations. For purposes of identification, the positions of navigational stars — expressed as declination and sidereal hour angle — are often rounded to the nearest degree. In addition to tables, star charts provide an aid to the navigator in identifying the navigational stars, showing constellations, relative positions, and brightness.
  • 2.5K
  • 26 Oct 2022
Topic Review
List of Traffic Separation Schemes
A Traffic Separation Scheme is an area in the sea where navigation of ships is highly regulated. It is meant to create lanes in the water and ships in a specific lane are all going in (roughly) the same direction. A TSS is created in locations with dense shipping where ships can go in different directions and where there is a high risk of collisions. In the overview below the regulating authority is always the IMO unless stated differently) If below TSS or Routing Scheme is not governed by the IMO the governing body will be mentioned between ' (brackets). 
  • 2.0K
  • 29 Sep 2022
Topic Review
List of Tropical Cyclone-spawned Tornadoes
Intense tropical cyclones usually produce tornadoes, the majority of those weak, especially upon landfall.
  • 1.0K
  • 03 Nov 2022
Topic Review
List of Volcanic Eruptions on Iceland
This is a list of recorded volcanic eruptions on Iceland.
  • 1.7K
  • 01 Nov 2022
Topic Review
LISWC System in Atlantic Canada
Landscape integrated soil and water conservation (LISWC) is a system designed to conserve and reuse soil and water within the landscape by integrating multiple BMPs based on an understanding of the landscape processes and knowledge about the BMPs. On a typical sloping field in Atlantic Canada, an LISWC system can be established by integrating BMPs such as diversion terraces and grassed waterways, tile drainage, water retention structures, supplemental irrigation, conservative tillage practices and soil–landscape restoration. 
  • 620
  • 18 May 2021
Topic Review
Lithium Recovery via Chemical Precipitation
Lithium is a vital raw material used for a wide range of applications, such as the fabrication of glass, ceramics, pharmaceuticals, and batteries for electric cars. The accelerating electrification transition and the global commitment to decarbonization have caused an increasing demand for lithium. The current supply derived from brines and hard rock ores is not enough to meet the global demand unless alternate resources and efficient techniques to recover this valuable metal are implemented. 
  • 4.5K
  • 21 Feb 2023
Topic Review
Litter Modification of Forest Fluxes
Litter can modify GHG fluxes often in gas-specific ways, although there are also common mechanisms underlying its effect, which are regulated by the environmental conditions, forest management and climate change factors.
  • 540
  • 27 Sep 2021
Topic Review
Livestock Management in Fire-Prone Shrublands of Atlantic Iberia
In the humid northwest of the Iberian Peninsula, large rural areas are being abandoned, mostly in less-favoured areas dominated by shrublands of low nutritive quality for livestock production. The high wildfire incidence has very negative environmental and economic effects. Aspects on wildfire occurrence and the potential of grazing livestock to reduce woody mass and fire risk whilst maintaining quality production and preserving biodiversity are summarized. Sustainable grazing systems are affordable in shrubland–grassland mosaics by selecting appropriate livestock species and breeds for quality production, thus favouring rural economies and lowering fire risk.
  • 313
  • 01 Apr 2022
Topic Review
Living on Coast in Harmony with Natural Processes
The coastal zone is a fascinating place that comprises the interface between sea and land. This interface, which is both very dynamic and sensitive, has been affected by strong urban and industrial pressures, and an increase in both traffic and recreational uses, leading to the deterioration of natural habitats and the growing instability of residential areas. Added to this disruption is ongoing climate change, which will lead to rising sea levels and increased wave action. Another problem we are increasingly concerned about is ocean pollution, which has been one of the main causes of threats to deep-water coral reef areas. The main sources of pollution include oil spills and offshore oil drilling. The effects of pollution caused by oil spills can not only seriously affect the global environmental balance of our planet but can also, on a different scale, seriously affect the economy of countries whose main resources depend heavily on the sea. Wave energy has the potential to alleviate the world's dependence on depleting fossil energy resources. With regard to coastal protection, the development of ecological solutions to preserve ecosystems and address coastal processes as an alternative to traditional coastal protection structures (seawalls, groins and breakwaters) is becoming increasingly important. These structures, generally referred to as passive measures, are usually built to alter the effects of sea waves, currents and the movement of sand along the coastline, with the aim of protecting beaches, ports and harbors. 
  • 154
  • 10 Nov 2023
Topic Review
Llanquihue Glaciation
The last glacial period and its associated glaciation is known in southern Chile as the Llanquihue glaciation (Spanish: Glaciación de Llanquihue). Its type area lies west of Llanquihue Lake where various drifts or end moraine systems belonging to the last glacial period have been identified. The glaciation is the last episode of existence of the Patagonian Ice Sheet. The preceding interglacial is known as the Valdivia interglacial after its type locality of Valdivia.
  • 570
  • 31 Oct 2022
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