Humidity in the air is measured with an instrument called a psychrometer. This is called air pressure. You experience high air pressure at sea level because the whole atmosphere is pushing down on you. The air in our atmosphere acts as insulation, keeping the Earth from getting too cold or too hot. Ozone, another type of gas in the air, also protects us from too much sunlight. Air in the atmosphere can also protect us from meteoroids.
When meteoroids contact our atmosphere, they rub against the air and oftentimes are burned into small pieces before reaching Earth. Lots of living things make their homes in soil and water. But did you know that living organisms can also be found hanging out in the air? These tiny microbial organisms are called bioaerosols.
Even on a very still day, the air around us is always moving. But when a big wind comes, that air can really go! It traps electrons negative charge and protons positive , concentrating them in two bands about 3, and 16, km above the globe - the Van Allen "radiation" belts.
This outer region surrounding the earth, where charged particles spiral along the magnetic field lines, is called the magnetosphere. Jump to Navigation Skip to main content. The different layers of the atmosphere The atmosphere can be divided into layers based on its temperature, as shown in the figure below. The Troposphere This is the lowest part of the atmosphere - the part we live in. The Stratosphere This extends upwards from the tropopause to about 50 km.
The Mesosphere The region above the stratosphere is called the mesosphere. The Thermosphere and Ionosphere The thermosphere lies above the mesopause, and is a region in which temperatures again increase with height. The Exosphere The region above about km is called the exosphere. The Magnetosphere The earth behaves like a huge magnet.
Climate change information for climate solvers. Helping you understand the science of climate change. Technicians release a balloon at Lauder. Chemical sensors attached will measure the vertical ozone profile up to an altitude of around 35 kilometres before descending.
Layers of the atmosphere. See original]. Related content. Media Release. Scientists reveal how landmark ban gave planet fighting chance.
Searching southern skies. By understanding the way temperature changes with altitude, we can learn a lot about how the atmosphere works. While weather takes place in the lower atmosphere, interesting things, such as the beautiful aurora, happen higher in the atmosphere. Why does warm air rise? Gas molecules are able to move freely and if they are uncontained, as they are in the atmosphere, they can take up more or less space.
Warmer, lighter air is more buoyant than the cooler air above it, so it rises. The cooler air then sinks down, because it is denser than the air beneath it. This is convection, which was described in the Plate Tectonics chapter. The property that changes most strikingly with altitude is air temperature.
Unlike the change in pressure and density, which decrease with altitude, changes in air temperature are not regular. A change in temperature with distance is called a temperature gradient. The temperature gradient of each layer is different. In some layers, temperature increases with altitude and in others it decreases. The temperature gradient in each layer is determined by the heat source of the layer. Most of the important processes of the atmosphere take place in the lowest two layers: the troposphere and the stratosphere.
Sometimes there is a temperature inversion , air temperature in the troposphere increases with altitude and warm air sits over cold air. Inversions are very stable and may last for several days or even weeks. They form:. Because of this, the ozone layer protects life on Earth.
High-energy UV light penetrates cells and damages DNA, leading to cell death which we know as a bad sunburn. Organisms on Earth are not adapted to heavy UV exposure, which kills or damages them. The mesosphere is extremely cold, especially at its top, about degrees C degrees F. The air in the mesosphere has extremely low density: As a result, air pressure is very low.
A person traveling through the mesosphere would experience severe burns from ultraviolet light since the ozone layer which provides UV protection is in the stratosphere below. There would be almost no oxygen for breathing. When massive solar storms cause the Van Allen belts to become overloaded with particles, the result is the most spectacular feature of the ionosphere — the aurora.
The particles spiral along magnetic field lines toward the poles. The charged particles energize oxygen and nitrogen gas molecules, causing them to light up.
Each gas emits a particular color of light. There is no real outer limit to the exosphere , the outermost layer of the atmosphere; the gas molecules finally become so scarce that at some point there are no more. Beyond the atmosphere is the solar wind. The solar wind is made of high-speed particles, mostly protons and electrons, traveling rapidly outward from the Sun. Can you think of some objects that appear to radiate visible light, but actually do not?
The moon and the planets do not emit light of their own; they reflect the light of the Sun. Reflection is when light or another wave bounces back from a surface.
Albedo is a measure of how well a surface reflects light. A surface with high albedo reflects a large percentage of light. A snow field has high albedo. One important fact to remember is that energy cannot be created or destroyed — it can only be changed from one form to another.
This is such a fundamental fact of nature that it is a law: the law of conservation of energy. In photosynthesis, for example, plants convert solar energy into chemical energy that they can use. They do not create new energy. When energy is transformed, some nearly always becomes heat. Heat transfers between materials easily, from warmer objects to cooler ones. If no more heat is added, eventually all of a material will reach the same temperature.
Which has higher heat and which has higher temperature: a candle flame or a bathtub full of hot water? HEAT Heat is taken in or released when an object changes state, or changes from a gas to a liquid, or a liquid to a solid. This heat is called latent heat. When a substance changes state, latent heat is released or absorbed. A substance that is changing its state of matter does not change temperature.
For example, imagine a pot of boiling water on a stove burner: that water is at degrees C degrees F. If you increase the temperature of the burner, more heat enters the water.
The water remains at its boiling temperature, but the additional energy goes into changing the water from liquid to gas. With more heat the water evaporates more rapidly. When water changes from a liquid to a gas it takes in heat. Since evaporation takes in heat, this is called evaporative cooling. Evaporative cooling is an inexpensive way to cool homes in hot, dry areas. Substances also differ in their specific heat , the amount of energy needed to raise the temperature of one gram of the material by 1.
Water has a very high specific heat, which means it takes a lot of energy to change the temperature of water. If you are walking barefoot on a sunny day, which would you rather walk across, the shallow puddle or an asphalt parking lot? Because of its high specific heat, the water stays cooler than the asphalt, even though it receives the same amount of solar radiation.
The earth constantly tries to maintain an energy balance with the atmosphere. When viewed together, all of the wavelengths of visible light appear white. But a prism or water droplets can break the white light into different wavelengths so that separate colors appear. Of the solar energy that reaches the outer atmosphere, UV wavelengths have the greatest energy. Only about 7 percent of solar radiation is in the UV wavelengths. The three types are:.
The remaining solar radiation is the longest wavelength, infrared. Most objects radiate infrared energy, which we feel as heat. Some of the wavelengths of solar radiation traveling through the atmosphere may be lost because they are absorbed by various gases.
Oxygen, carbon dioxide, and water vapor also filter out some wavelengths. Heat moves in the atmosphere the same way it moves through the solid Earth Plate Tectonics chapter or another medium.
What follows is a review of the way heat flows and is transferred, but applied to the atmosphere. Radiation is the transfer of energy between two objects by electromagnetic waves. Heat radiates from the ground into the lower atmosphere.
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