Atmosphere composition and altitude
The atmosphere is composed of different gases, including nitrogen (78%), oxygen (21%), argon (0.93%), carbon dioxide (0.04%) and other trace gases such as neon, helium, methane, and ozone. The composition of the atmosphere varies with altitude, as the density of gases decreases as altitude increases.
When we move up in altitude from sea level, the air pressure decreases, and the concentration of the gases in the atmosphere also changes. At higher altitudes, the air is thinner, and the concentration of oxygen and other gases decrease. For example, at an altitude of around 10 kilometers, the concentration of oxygen in the atmosphere is around 14%, compared to 21% at sea level.
Moreover, the layers of the atmosphere differ in temperature, pressure, and composition. The troposphere, which is the lowest layer and where weather occurs, is where most of the Earth's mass of air is concentrated, and as altitude increases, the temperature decreases. The stratosphere, above the troposphere, has higher concentrations of ozone, which helps protect us from harmful ultraviolet radiation. The mesosphere and thermosphere are higher up and become increasingly thin, with low concentrations of gases. These changes in composition and altitude of the atmosphere have significant impacts on the Earth's weather, climate, and the ability of humans and other living organisms to survive.
The Earth's atmosphere is composed of various gases, with the majority being nitrogen (about 78%) and oxygen (about 21%). Here is a breakdown of the composition of the Earth's atmosphere by volume:
1. Nitrogen (N2): Approximately 78%
2. Oxygen (O2): Approximately 21%
3. Argon (Ar): Approximately 0.93%
4. Carbon Dioxide (CO2): Approximately 0.04%
5. Other trace gases such as neon, helium, methane, and ozone: Collectively make up less than 0.1%
The composition of the atmosphere can vary slightly with altitude, but the percentages mentioned above provide a good overall representation of the gases in the Earth's atmosphere.
Altitude refers to the distance above sea level or the height at which a point or location is located in the atmosphere. It is typically measured in units like meters or feet. As altitude increases, the atmospheric pressure and temperature generally decrease.
The atmosphere can be divided into different layers based on altitude. These layers are:
1. Troposphere: This is the lowest layer of the atmosphere, extending from the Earth's surface up to an average altitude of about 7-16 kilometers (4-10 miles) depending on the location. It is where weather occurs, and temperature generally decreases with increasing altitude.
2. Stratosphere: Located directly above the troposphere, the stratosphere extends from the top of the troposphere to an average altitude of about 50 kilometers (30 miles). The ozone layer, which absorbs and filters a significant amount of the Sun's ultraviolet radiation, is found in this layer. In the stratosphere, temperature generally increases with increasing altitude.
3. Mesosphere: Above the stratosphere lies the mesosphere, which extends up to an average height of about 85 kilometers (53 miles). In this layer, temperatures gradually decrease with increasing altitude.
4. Thermosphere: Located above the mesosphere, the thermosphere extends up to an altitude of about 600 kilometers (370 miles). This layer experiences extremely high temperatures due to the absorption of solar radiation. However, the thermosphere would feel very cold to human perception due to its extremely low density. The International Space Station orbits within this layer.
5. Exosphere: The outermost layer of the atmosphere is the exosphere, which gradually transitions into space. It extends from the upper boundary of the thermosphere to several thousand kilometers above the Earth's surface. In this layer, the gases gradually become less dense and individual atoms and molecules can escape into space.
Keep in mind that the altitude ranges mentioned for each layer are approximate and can vary based on factors like latitude and weather conditions.