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nWhatnhave mountains done for you lately?
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Asidenfrom the obvious—being places of beauty and wildlife and winternplay in the snow—mountains often cause rain to fall, hold much ofnthe world’s fresh water supply, and help to create beaches.
Asidenfrom the obvious—being places of beauty and wildlife and winternplay in the snow—mountains often cause rain to fall, hold much ofnthe world’s fresh water supply, and help to create beaches.n
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nMountainsnCause Rain?
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nWhennbreezes carry moist air from the oceans inland, that moisture oftennremains invisible, as water vapor. But if the air begins to cool asnit blows against mountains and is forced upward, the water vapornforms drops, and now we can see it: it forms a cloud. If the air isnmoist enough, and if it gets cool enough, the drops forming the cloudnbecome so large and heavy that they fall to the ground as rain,nsleet, hail, or snow (depending on conditions). n
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nYouncan see how often mountains cause rain by studying yearlynprecipitation totals. The areas on the seaward side of mountainnranges often enjoy much more rainfall per year than the otherwisensimilar areas on the other side of those mountains. The moisture hasnbeen forced out of the air on the seaward side of the mountains; bynthe time it has reached the other side of the mountains, and beginsnto sink and warm, there is often no more moisture for rainfall. Thesendry areas are considered to be in the mountains’ rain shadow.
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nMountainsnHold Fresh Water?
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nMountainsncollect and hold much of the year’s precipitation as snow and ice andnthen release it during warmer—and usually drier—times of thenyear.
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nAlso,nbecause mountains cause a lot of rainfall as well as snowfall, theynare often dotted with freshwater lakes. This water tends to movendownhill in creeks and then gather into rivers. n
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Innsemi-arid and arid regions, 70 to 90 percent of river flows come fromnthe mountains, and even in moister areas, 30 to 60 percent ofnfreshwater comes from mountains. All the major rivers in the worldnhave their headwaters in mountains. Half of all the people in thenworld depend on mountain water for drinking, as a source of energy ornincome, or for growing food. (I found all these incredible statisticsnhere.)
Innsemi-arid and arid regions, 70 to 90 percent of river flows come fromnthe mountains, and even in moister areas, 30 to 60 percent ofnfreshwater comes from mountains. All the major rivers in the worldnhave their headwaters in mountains. Half of all the people in thenworld depend on mountain water for drinking, as a source of energy ornincome, or for growing food. (I found all these incredible statisticsnhere.) n
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nMountainsnhelp create beaches?
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| Sand grains are incredibly varied and surprisingly beautiful. |
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nAsnthe creeks and rivers flow downhill from mountains, they erode rocksnand carry particles of rock to the oceans. Whenever the rushingnrivers are forced to slow down, they dump a lot of the rock particlesnthey are carrying. This creates fertile, mineral-rich soil fornfarming as well as beautiful sandy beaches.
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nActually,nwe humans get a lot of important ores and minerals from mining innmountainous areas, and fossil hunters often benefit from erosion innuplifted areas, too.
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Celebratenmountains!
Celebratenmountains!n
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nYouncan either head for the hills, drink a toast of tap water (whichnprobably originated in mountains somewhere), or browse through somenmountain loveliness herenor here or here.
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nAlsonon this date:
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Physicist Max Born’s birthday
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nProclamation of the Republic Day in Burkina Faso
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nAnniversary of the first recorded sighting of the Aurora Borealis in America
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