This unequal heating causes vertical motion of air warm air rises as it expands. Advection is the horizontal transfer of air, we often refer to this as fronts. When the wind moves warm air over a colder area we call this warm air advection.
Latent heat is the heat that is stored by water molecules when they change state into a higher energy level. If you take a pot of boiling water you will see the temperature remains around degrees C, regardless of the fact that the heat source continues to add heat to it. Where does this additional energy go?
Into the water molecules themselves, as they convert to water vapor. So if we have water vapor in a warm air parcel, and that parcel rises and cools due to the decrease in pressure , we will see the water vapor change back into liquid water forming a cloud and the latent heat will be released as sensible heat heat you can feel. This works hand in hand with Convection. Finally we have something called turbulent mixing.
The exchange and movement of water between the earth and atmosphere is called the water cycle. The cycle, which occurs in the troposphere, begins as the sun evaporates large amounts of water from the earth's surface and the moisture is transported to other regions by the wind. As air rises, expands, and cools, water vapor condenses and clouds develop. Clouds cover large portions of the earth at any given time and vary from fair weather cirrus to towering cumulus clouds. When liquid or solid water particles grow large enough in size, they fall toward the earth as precipitation.
The type of precipitation that reaches the ground, be it rain, snow, sleet, or freezing rain, depends upon the temperature of the air through which it falls. As sunlight enters the atmosphere, a portion is immediately reflected back to space, but the rest penetrates the atmosphere and is absorbed by the earth's surface. This energy is then remitted by the earth back into atmosphere as long-wave radiation.
Carbon dioxide and water molecules absorb this energy and emit much of it back towards the earth again. This delicate exchange of energy between the earth's surface and atmosphere keeps the average global temperature from changing drastically from year to year. Heat moves naturally by any of three means. The processes are known as conduction, convection and radiation. Sometimes more than one may occur at the same time. The troposphere gets some of its heat directly from the Sun.
The surface is heated by the Sun. Some of that heat radiates back into the air. This makes the temperature higher near the surface than at higher altitudes.
The troposphere is coldest at its top, where it meets up with the layer above the stratosphere at a boundary region called the tropopause. Temperatures drop as you move upward through the troposphere. In fact, the troposphere contains three-quarters of the mass of the entire atmosphere. The weather we experience on earth, including rain, thunderstorms, lightning, wind, tornadoes, hurricanes, typhoons and even gentle breezes, occur within the troposphere. Water vapor it important as it will absorb solar energy and thermal radiation from the surface of Earth, thus regulating the air temperature.
There are three ways heat is transferred into and through the atmosphere:. If you have stood in front of a fireplace or near a campfire, you have felt the heat transfer known as radiation. The side of your body nearest the fire warms, while your other side remains unaffected by the heat. Although you are surrounded by air, the air has nothing to do with this transfer of heat.
Heat lamps, that keep food warm, work in the same way. Radiation is the transfer of heat energy through space by electromagnetic radiation. Most of the electromagnetic radiation that comes to the earth from the sun is invisible. Only a small portion comes as visible light. Light is made of waves of different frequencies.
The frequency is the number of instances that a repeated event occurs, over a set time. In electromagnetic radiation, its frequency is the number of electromagnetic waves moving past a point each second. Our brains interpret these different frequencies into colors, including red, orange, yellow, green, blue, indigo, and violet. When the eye views all these different colors at the same time, it is interpreted as white.
Waves from the sun which we cannot see are infrared, which have lower frequencies than red, and ultraviolet, which have higher frequencies than violet light.
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