Test: Atmosphere - 2 - ACT MCQ

The troposphere is the atmospheric layer closest to the ground. It is where weather occurs and where most of Earth's air mass is located. This layer extends from the Earth's surface up to an average height of about 7-20 kilometers. The temperature in this layer generally decreases with altitude, and it is where we live and breathe.

The mesosphere is the third atmospheric layer from the ground. It is located above the stratosphere and below the thermosphere. This layer is characterized by a decrease in temperature with increasing altitude. It is also the layer where meteors burn up upon entering the Earth's atmosphere.

The aurora borealis, also known as the Northern Lights, is a natural light display that occurs in the upper atmosphere. It is caused by the interaction between the Earth's magnetic field and charged particles from the sun. The thermosphere is the layer of the atmosphere that is closest to outer space and is characterized by high temperatures. This is where the aurora borealis occurs, making it the correct answer.

The ozone layer acts as a shield, protecting us from harmful ultraviolet (UV) radiation emitted by the sun. UV radiation can cause various health issues, including skin cancer, cataracts, and weakened immune system. The ozone layer absorbs and filters out most of the UV radiation, allowing only a small amount to reach the Earth's surface. This crucial role of the ozone layer makes it essential for the preservation of life on our planet.

The troposphere is the layer of the Earth's atmosphere where weather occurs. It is the lowest layer of the atmosphere and extends from the Earth's surface up to about 8-15 kilometers. This layer is characterized by decreasing temperature with increasing altitude and contains most of the Earth's weather systems, such as clouds, precipitation, and storms. The other layers mentioned, the stratosphere, thermosphere, and mesosphere, are located above the troposphere and do not experience as much weather activity.

The thermosphere is the hottest layer in the atmosphere. It is located above the mesosphere and extends up to the exosphere. This layer is characterized by extremely high temperatures due to the absorption of solar radiation. The thermosphere is also where the International Space Station orbits.

Oxygen makes up around 21% of our atmosphere. It is an essential gas for supporting life as it is required for respiration in most organisms. Oxygen is produced through photosynthesis by plants and algae, and it is also released into the atmosphere by certain bacteria. It is necessary for the combustion of fuels and plays a crucial role in the ozone layer, which protects us from harmful ultraviolet radiation from the sun.

As you go higher in the troposphere, the temperature decreases. This is because the troposphere is the lowest layer of the Earth's atmosphere, and it is closest to the surface. The temperature in the troposphere decreases with altitude due to the decrease in air pressure. As the air pressure decreases, the air molecules spread out and the heat energy becomes less concentrated, resulting in a decrease in temperature. Therefore, it gets colder as you go higher in the troposphere.

Water vapor and other gases make up less than 1% of the atmosphere. The atmosphere is primarily composed of nitrogen (about 78%) and oxygen (about 21%). Carbon dioxide, although a greenhouse gas, only makes up a very small percentage of the atmosphere (about 0.04%). Water vapor and other gases, such as argon, neon, helium, and methane, make up the remaining fraction, which is less than 1%. These gases have a smaller presence in the atmosphere compared to nitrogen and oxygen.

The troposphere is the atmospheric layer closest to the Earth's surface, extending up to about 10-15 kilometers. This layer is where most weather phenomena occur, including the formation of clouds. The troposphere is characterized by decreasing temperature with increasing altitude, which allows for the condensation of water vapor and the formation of clouds. Therefore, it is reasonable to conclude that the troposphere has the most clouds compared to the other atmospheric layers mentioned.