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The Mountain Environment and Effects on World Climate

Mountains have a profound influence on not only their local climate and immediate vicinity, but sometimes in areas a thousand or more milesaway. This is due to the fact that mountains, jutting up into an otherwise orderly flow of winds around the globe, cause these winds to be liftedup, over and around the peaks and ridges.

The forcing of the air to rise causes it to cool and condense, forming clouds and precipitation; this makes the mountain environment muchwetter than the surrounding lowlands.

The other thing is that as one goes higher in a mountain environment it gets colder and colder — but why? After all, you are getting closer tothe sun, right? Well, yeah, you are closer to the sun on a mountain than at sea level, but not enough to make any difference. I mean, whencompared to our distance from the sun, the mountain heights are extremely insignificant. In fact, if the earth was shrunk down to the size of acue ball, it would be more perfectly round and smooth than the cue ball — you couldn't even feel Mt. Everest!

(Wow! That makes me feel tiny; I mean, compared to us, the earth is HUGE!)

OK, so the reason it gets colder the higher one goes is because of the ever-thinning air. This thin air holds less water and thus absorbs less

heat. The higher you go, the thinner the air is and thus the effect of not holding any heat gets more profound.

For example, at Everest Base Camp, around 18,000 feet (5,486 m.), it can be quite comfortable on a sunny summer day with no wind, but assoon as the sun disappears behind thick cloud cover or a mountain, the temperature plummets, often to near zero degrees F. Also there is amarked difference in temperature in just stepping into the shade of a large boulder.

So anyway, as you climb higher in a mountain environment the temperature on average drops 2 - 5 degrees F. for every 1,000 feet (305 m.)gain in altitude. However this can vary throughout the day or season, or at different latitudes. During certain weather conditions, this canactually reverse, and it can be colder at the surface than at moderate altitudes. However, this phenomenon is usually very short-lived and hasno effect on the overall mountain climate.

If it were not for mountains interfering with the great flow of wind currents around theearth, the overall world climate would be far less complicated. For example, within

just a few hund red miles from each othe r in South America, are the Atacama Deser tand the Amazon Rainforest. The primary reason for these opposite extremes is thegreat Andes mountain range which forms a barrier between the two, thus preventingany rain in the Atacama and actually enhancing rainfall in the Amazon.

The Atacama is considered the driest desert in the world and some areas of it havenot received any significant rainfall in at least 400 - 500 years!

By combining the differences in precipitation and temperature brought about bydifferent altitudes, a single mountain range can have a great variety of climate zonesand biodiversity. One of the best examples of this is the mystical RwenzoriRange (The old spelling is: Ruwenzori), also known as The Mountains of the Moon, in

Africa.

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Why is it colder at a higher altitude when technically it is closer to the sun?

Answer 1:

This is a great question, but the answer is a little complicated, so youhave to help me out.

First, we have to understand air pressure. A lot of people think thatair has no weight. This is not true. Air is matter and it has mass.“Mass” is a fancy way of saying “stuff.” We measure the mass byweighing it.

Picture yourself standing by the foot of a mountain. There is acolumn of air on you that goes all the way up into the end of our atmosphere. It is pushing down on you, but you don’t notice it. (If weswapped in water for air, you would.) Now picture yourself on thetop of the mountain. The column of air is shorter now, so it weighsless. It is putting less pressure on you. Got that? More air pressuredown by sea level, less on the top of the mountain.

Pressure squishes things down so that they take up less space.“Volume” is a fancy way of saying “space.” The same amount of air is squashed into a smaller space down at sea level. On top of themountain, it is more spread out.

Heat is energy, not stuff (matter). We can’t see heat. We measure itas temperature.

This part is tricky, so help me out by grabbing a piece of paper, aruler, a pencil, and a red crayon or marker.

1. Draw a square with the pencil. Make the square about 2 inches oneach side.2. Now use the red crayon or marker to draw 20 lines from the top to

the bottom of the square, partly filling it in.3. Next to this, use the pencil to draw a second square that is about3 inches on each side.4. Now use the red crayon or marker to make 20 lines, each one 2inches long, inside the big square.

In your drawing, the red lines are to show heat. You can see that alot less of the big square is covered by red. If you were an antwalking around in the big square, you would touch a lot less heat.

When air is near sea level, air pressure squashes it into a smallspace, like your small square. When the air is high on the mountain,it spreads out. This is like your big square. The same amount of heatis now in a bigger space, so it is more spread out. So the air is colder on top of mountains because there is less air pressure.

Heat is not really red, and it’s not really lines. The picture that youdrew helps you think about heat. Your picture is a model. Scientistsuse models to help themselves think about things and tocommunicate to other people.

Some places on land are actually below sea level. Do you think theyare hotter or cooler than places at sea level?

If you like to think about this sort of question, you may want to studyatmospheric science.

Thanks for asking,

Answer 2:

So you know that the sun is really hot, but space is really cold. Sincethe temperature of the Earth is so much hotter than space, you’dexpect that the closer you get to space the colder it gets. Eventuallyas you get closer to the sun, the temperature will start to increase.You may have heard people say that the air is “thinner” at higher altitudes. What this means is that it is less dense. Generally, the lessdense air is, the colder it is. So the air is densest closest to thesurface of the Earth, then it gradually becomes less dense until youget to the vacuum of space. This density difference accounts for thetemperature difference.

Answer 3:

At higher altitudes, the air is thinner. That's why it's harder to breathe

at high altitudes--there's less oxygen. There's also less of everything

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else--carbon dioxide, water vapor, etc. These gases, which aregreenhouse gases, are the part of our atmosphere which keep Earthat a warm temperature compared to outer space. Without thisatmosphere, Earth would be uninhabitably cold. So, even thoughhigher altitude areas are closer to the sun, they have less ability toabsorb the warmth of the sun because they have less of thesegases.

Answer 4:

Good question!

When air expands, it has to push the surrounding air out of its way,which means that it expends part of its energy to do the pushing. Asa result, the expanding air cools. When air contracts, it gets pushedinto a smaller space by the air around it, which means that energy isput into it, which heats it up. Eventually, the expanding or contractingair will reach the same temperature and pressure as the air surrounding it, and the heating and cooling will stop. Air at higher altitude is under less pressure than air at lower altitude becausethere is less weight of air above it, so it expands (and cools), whileair at lower altitude is under more pressure so it contracts (and heatsup).

Air in our atmosphere moves up and down as part of the weather:the sun heats up the ground (which absorbs more light than air andis thus warmer than the air), and the air in contact with the ground

heats up, and expands (and then cools). Elsewhere, cooler higher-altitude air sinks, is compressed as it descends, and gets heated asthis occurs. This process is called "convection", and it is responsiblefor nearly all of our weather.

Answer 5:

You are correct that it is colder at higher altitudes. However, thedistance to the sun has nothing to do with this – it is the lower atmospheric pressure that results in lower temperatures. Keep inmind that the Sun is about 93 million miles (490 billion feet) awayfrom Earth. Even if you hiked to the highest point in Santa Barbara(La Cumbre Peak: 4,000 ft) or were flying in a commercial airplane(cruising altitude ~ 30,000 ft), you are still relatively the same

distance from the Sun (REALLY far away).

The answer to your question deals with the pressure andtemperature relationship of a gas. The Earth's atmosphere is thinlayer of gases composed of nitrogen (78%), oxygen (19%), andother gases (~3%). As you go to higher altitudes, there are less air molecules pushing down on you (lower pressure). When thepressure of a gas decreases, the temperature also decreases (thereverse is also true – when the gas pressure increases, thetemperature increases). Therefore, the air temperature is lower athigher altitudes.

Hope this helps!

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Add y our answer

WHY MOUNTAINS ARE COLDER THANPLAINS?

As it is well known t hat as we move towards hight, it becomes colder..... the

high places should be hotter as they are a little close to sun !!!!

2 following 3 answers

Answers

Comment

Best Answer: The distance to the sun has absolutely nothing to do with

this. The fact is that the temperature sinks with altitude with an average of

0.65 C per 100 meter (3 F per 1,000 ft) The reason is: Air doesn't get warmed

up by the sun's energy. At least, not at our under the stratosphere. What gets

warmed up is the ground. That warms up a thin lay er of air right above it and

since warmer air is lighter, it rises.

But because the higher you get, the lesser the atmospheric pressure is, that

rising air cools down by the so-called adiabatic effe ct. This is the same

thermodynamic principle that cools down your fridge when a compressed

coolant is released through a nozzle.

Therefore the higher you get, the colder it is. At the altitude an airliner flies, the

outside temperature is around -50 C (-58 F).

But sometimes things are different. If ther e is no wind at all, during the night

the cold air from the hills surrounding a valley will sink down because colder air

being denser, is also heavier. In fact, it can creat e a wind called a katabatic

wind. In the early morning, the air down in the valley will then be colder than up

in the hills or mountains.

If you ever see fog down in a valley, you'll know that this is what happened.

Because colder air probably mixed with moist air (lakes and rivers are usually

down in valleys) is what is needed to form fog. And since the air above is

warmer, it forms what is called an inversion: Cold air under warm one. And

nothing moves ... until the sun, again, warms up the ground during the day.

Michel Verheughe · 6 years ago

0 0

Comment

I think it just happens that the mountains tend to not be as near the eq uator,

so they're colder. Whereas plains are usually near it.

Megan · 6 years ago

0 0

Comment

In plains heat reflects equally but in the mountains less heat reflection.

Mohan · 6 years ago

0 0

WHY MOUNTAINS ARE COLDER THAN PLAINS?

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