O’Phelan Stephanie
Chpt. 8
1. List the components that make up air and diagram the atmosphere layers, labeling each one and its approximate location. Explain why most of the atmosphere is in the two lower levels.
The four major components of the air are Nitrogen (78.08%), Oxygen (20.95%), Argon (0.93%) and Carbon dioxide (0.03%), all other gases make up (0.01%) of the atmosphere.
Atmosphere:
Thermosphere ( beyond 11,000 meters – into space)
Mesosphere (90,000 meters)
Stratosphere (50,000 meters)
Troposphere (15,000 meters)
Most of the atmosphere is in the two lower levels because air compresses under its own weight so all of the mass of the atmosphere stays closer to the Earth.
2. Describe what causes rain and snow. How does the relationship between water vapor, air temperature and air density relate?
Rain and Snow can occur warm air reaches a cool part of land or when a cool air mass meets a warm air mass. As the temperature rises air pressure increases and density decreases. The differences in the densities of air cause precipitations where warm moist air is less dense than cool air.
3. About what percentage of sunlight reaches Earth’s surface? Explain why the Earth doesn’t grow hotter despite all the sunlight that falls on it. What would happen if this process became imbalanced? What might cause an imbalance?
55% of the suns light reaches the earth’s surface. The Earth does not grow hotter because 20% of the incoming energy is absorbed by clouds and the atmosphere, 25% is reflected by clouds and atmosphere, 50% absorbed by ocean and land and 5% reflected by ocean and land. If this process became imbalanced Earth could not be habitatble in many parts, an imbalance can be caused by the depletion of the ozone layer.
4. Identify the factors that make the earth heat unevenly and why they do so. What is it summer in the northern hemisphere even though the earth is farther from the sun than it is in winter?
The earth heats unevenly because it is spherical therefore receives light at different angles, the earth is tilt because the suns rays are not constantly hitting the equator perpendicularly, they tend to go between the tropic of cancer and the tropic of Capricorn, and the earth is farther away from the sun at different times of the year. It is summer in the northern hemisphere because although the earth is tilted away from the sun, the temperature is minimally different.
5. Describe the process of convection and how it relates to airflow on earth. How does the relationship between water vapor, air temperature and density relate to convection?
Convection is when the hot air rises making it less dense and then cool air sinks to where the warm air was. On Earth we can see hot air in the equator rise and go towards either pole and cool air from the pole head towards the equator. The relationship of water vapor, air pressure and density relate because as the air changes temperature it changes the amount of water vapor it holds as well as decreasing density with temperature increase.
6. Explain what causes the Coriolis effect and what influence it has on the wind.
The Coriolis effect has a major role in water currents and the distribution of heat. Without it, wind would only blow to and from the south. The Coriolis effect explains that there is a pattern where objects deflect to the right in the Northern Hemisphere and to the left in the Southern Hempishere, this is mostly caused by the Earth’s rotation.
7. Explain where the trade winds and the westerlies are found and explain what causes them. Include the role of atmospheric circulation cells and describe the airflow patterns that characterize the six global cells.
The Trade winds are found closest to the equator from 0-30 degrees, it is causes because by the time the hot air that rose reaches 30 degrees it is cool enough to sink again and head towards the equator once more. The westerlies are found between 30 and 60 degrees and occur because some of Hadley’s cells continue on to the poles and blow from the west to the east. These are atmospheric circulation cells and are crucial towards distribution of heat and for sailors or water currents.
8. What is the meteorological/ ITCZ equator and why does it move?
The ITCZ equator is an imaginary line marking the balance of temperatures on both hemispheres. It moves based on seasons and landmasses because they have a lower heat capacity than water and there is more land in the Northern Hemisphere than there is in the Southern Hemisphere.
9. Explain why the Earth’s major deserts exist at approximately 30 degrees latitude. How does this affect the salinity of nearby oceans?
Most deserts exist at approximately 30 degrees latitude because there is a downward flow of air, leading to more evaportation and very little rainfall. Not coincidentally, these are the characteristics of a desert. The salinity of near by oceans is much higher because more water is evaporating from the ocean and not a lot of it is being returned.
10. How do monsoons, extratropical cyclones and tropical cyclones differ? How are the similar?
Tropical cyclones occur only in a specific atmospheric “cell” while extratropical cyclones have also been found to form at higher latitudes. They are all cause much rain around the summer time. Both extratropical and tropical cyclones form by spiraling inwards as they are pulling from moist winds into a low pressure area. A tropical cyclone reaches typhoon or hurricane strength while an extratropical cyclone does not.
11. Explain how cyclones form and where they get their energy. Include their role in redistributing the Earth’s heat. Draw diagrams to show how their rotation develops.
Extratropical and tropical cyclones form by spiraling inwards as they are pulling from moist winds into a low pressure area. As more rain storms form they release heat causing the air to become less dense therefore also reducing air pressure. As air pressure falls once more, the cyclone gains “strength” as it is able to pull more air into its center and continues to spiral and intensify.