In the earths atmosphere, pressure, which is related to the number of molecules per unit volume, decreases exponentially with altitude. Thus, if a parcel of air from the surface rises because of wind flowing up the side of a mountain, for example , it undergoes an expansion, from higher to lower pressure.
When you allow air to expand, it cools. This phenomenon is familiar to everyone--stick your finger on the valve of a car tire, and let some air escape. It is not cool inside the tire, but as the air comes out it expands and thus cools. Michael Tinnesand, associate director for academic programs at the American Chemical Society, provides the following explanation: The basic answer is that the farther away you get from the earth, the thinner the atmosphere gets.
Rough, unpredictable, they're likely to bounce off each other, and run riot through the streets, and go to nightclubs with guns stuck in the waistbands of their jean shorts. They're at a high energy and that makes for a high temperature. Meanwhile, high altitude air molecules wander in solitude, a pack on their back and a cranky yak carrying their tent behind them. They have more space to wander around in, and because they don't bounce off each other as much, because they're not crammed into a small space by the pressure of the air above them, each square inch has a much lower temperature than sea level air.
Which is why, if you're climbing Mount Everest, you should bring a sweater. It's the same reasoning that causes temperature fluctuations at sea level. Low Pressure systems generally are storm systems, and as air goes upwards in a storm, air is cooler. The answer to your question deals with the pressure and temperature relationship of a gas. As you go to higher altitudes, there are less air molecules pushing down on you lower pressure.
When the pressure of a gas decreases, the temperature also decreases the reverse is also true — when the gas pressure increases, the temperature increases. Therefore, the air temperature is lower at higher altitudes. 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 you have to help me out. Picture yourself standing by the foot of a mountain. There is a column of air on you that goes all the way up into the end of our atmosphere. If we swapped in water for air, you would. Now picture yourself on the top of the mountain. The column of air is shorter now, so it weighs less. It is putting less pressure on you. Got that?
More air pressure down by sea level, less on the top of the mountain. Heat is energy, not stuff matter. We measure it as temperature. Draw a square with the pencil. Make the square about 2 inches on each side.
The standard or close-to-average atmospheric pressure at sea level is about However, the atmospheric pressure does not always equal this standard value due to changes in the weather. What is considered high air pressure?
A barometer reading of 30 inches Hg is considered normal air pressure. Similarly, a reading of If the air pressure falls below How does air pressure affect us? Air pressure is the weight of the atmosphere around us.
It affects us in different ways.
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