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Ice divide

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Anice divideis the boundary on anice sheet,ice caporglacierseparating opposing flow directions ofice,analogous to awater divide.Ice divides are important forgeochronologicalinvestigations that useice cores,since such coring is typically made at highest point of an ice sheet dome to avoid disturbances arising from horizontal ice movement. Ice divides are used for looking at how the atmosphere varied over time. Coring at dome peaks increases precision of reconstructions as it is the place where horizontal motion is at its least. TheRaymond Effectoperates at ice divides, creatinganticlinesin theradar-detected isochrones, allowing greater capture of older ice when coring.

Analysis of ice cores relies on the downward motion of ice, trapping changes of atmospheric gases through time into its layers. Scientist locate ice divides and take ice cores from them, which are typically long cylindrical poles of ice, and analyse them to find chemical elements that the snow and ice transported during that period, e.g. sulfate, nitrate, and other ions. Ice cores are important in determining how our atmosphere has changed, and how we can remedy changes such as thegreenhouse effect;scientists found moregreenhouse gaseswere in our atmosphere at present than in the past.[1]

Scientists from around the United States came together to find the best ice divide in order to go further into the past. They founded theWAIS project,which is funded by the United States National Science Foundation, and is run by scientists from many organizations e.g.National Ice Core Laboratory,Ice Drilling Design and Operations (IDDO), and over fifty universities. The WAIS project is located in West Antarctica, and the goal is to look into the evolution of theAntarctic ice sheetandclimateover the past 100,000 years. TheWest Antarctic Ice Sheet(WAIS) is better than other ice divides because of the amount of snow it gets, which means that the layers of ice are thicker. This larger layer thickness means there is a smaller off-set between the ages of the ice and that of the air and gases trapped inside, allowing scientists to make more precise statements about how the atmosphere varied in the past. The success of the WAIS project has educated scientists around the world as to how the atmosphere of Earth has changed dramatically over 100,000 years.[2]

References

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  1. ^University of Copenhagen. (2012). Centre for Ice and Climate. Retrieved December 6, 2012[dead link][permanent dead link]
  2. ^"National Science Foundation. (2012, December 6). Science. Retrieved December 6, 2012, from WAIS Divide Ice Core website".Archived fromthe originalon 2013-07-05.Retrieved2013-07-01.