<span>Air pressure decreases as you move higher in the atmosphere. Think of a column of air directly over your body. ... Just as air pressure decreases with altitude, so does the density of air.</span>
Millibar values used in meteorology range from about 100 to 1050. At sea level, standard air pressure<span> in millibars is 1013.2. Weather maps showing the </span>pressure<span> at the surface are drawn using millibars. ... This </span>change<span> in </span>pressure<span> is caused by </span>changes<span> in </span>air<span> density, and</span>air<span> density is related to temperature.
They have the same density because a material, no matter how much of it there is, will always be a certain density. A 40g ball of iron has the same density as a 1g ball of iron.
