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Q: SNOW ON MOUNTAIN PEAKS IN SUMMER ( Answered,   0 Comments )
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 Subject: SNOW ON MOUNTAIN PEAKS IN SUMMER Category: Science > Earth Sciences Asked by: anjet-ga List Price: \$10.00 Posted: 31 Dec 2002 07:38 PST Expires: 30 Jan 2003 07:38 PST Question ID: 135479
 ```IN THE SUMMER WHY IS THERE SNOW ON MOUNTIAN PEAKS WHEN THE TEMPERATURE AT THE BASE OF THE MOUNTIAN IS WELL ABOVE FREEZING?```
 ```Hello Anjet, At the Straight Dope website I found a similar question to yours. ============================================= Why is there snow on mountains in the summer? ============================================= The reason that there is snow on mountains in the summer is that it hasn't melted yet. Several factors go into the speed with which the snow will melt. The temperature decreases with altitude: “As you go higher, the temperature decreases. This is due to the fact that the earth stores heat from the sun, and the higher you go, the less earth there is around you. Obviously, the colder it is, the more time it will take for the snow to melt. The next factor is the sun: it has a bit of a warming effect, so even if the outside temperature is 32 degrees Fahrenheit, the surface snow will want to melt because the sun is beating down on it. The next factor is the volume of snow: the more there is, the longer it will take to melt, because the snow underneath the surface will have a cooling effect on the surface which is counteracting the warming effect of the sun and air. This is easily demonstrable in your own backyard: put a one-pound block of ice next to an ice-cube on your patio on a warm summer day and see which melts first.” Source: Straight Dope Website http://www.straightdope.com/mailbag/msnow.html ============================================ Why Does Temperature Decrease With Altitude? ============================================ “Air is thinner at higher elevations. There are fewer heat-absorbing gases to absorb and reradiate earth’s heat” http://members.aol.com/pakulda/tdpptnts.htm “Increase in altitude results in a decrease of air pressure, molecules that were once packed tightly together have now spread out and are less dense. Earth is reradiating heat in long-waves, which are not as hot as the incoming short-waves” http://www.u.arizona.edu/~jacquels/Temperature.htm ============ The Snowline ============ The lowest elevation at which snow remains on a mountain during the summer is called the snowline. A mountain that has no snow in the summer has no snowline. The snowline moves up and down a mountain seasonally - lowest in late winter and highest in late summer. “The snowline is related to air temperature, which in turn is influenced by elevation and distance from the Equator: air temperature drops as elevation increases and distance from the Equator increases. Even in areas near the Equator, there are some mountains that have snow year-round at their highest elevations, whereas in Polar Regions permanent snow can be found close to sea level during the summer months. The snowline is highest - that is, less of the mountain is covered with snow in the summer - on mountains closest to the Equator. The snowline is lowest on land closest to the poles. The greater the distance from the Equator, the less elevation is necessary to establish a snowline. The snowline also is influenced by the amount of yearly snow fall. Thus, the snowline may not be the same for all mountains at the same latitude.” Source: U.S. Geological Survey Lesson Plans http://interactive2.usgs.gov/learningweb/teachers/volcanoes_lesson4_2.htm Additional information that may interest you: Temperature Changes and Altitude http://newton.dep.anl.gov/askasci/env99/env029.htm Search Criteria: why is there snow in the mountains Altitude and temperature snowline Thank you for your question and I hope this response has provided you with the information you were seeking. Best Regards, Bobbie7-ga```