ATMOSPHERE BASICS
Identify the three most abundant gases in Earth’s atmosphere and their approximate percentages.
Nitrogen (78%), Oxygen (21%), Argon + trace gases (~1%)
Why does temperature generally decrease from the equator toward the poles?
Solar energy is spread over a larger area and reflected more at higher latitudes
What is the ultimate source of all wind on Earth?
The Sun
What is upwelling?
The vertical movement of cold, nutrient-rich deep water to the surface
Differentiate weather from climate.
Weather is short-term atmospheric conditions; climate is long-term (30+ years) averages
By approximately how much has global average temperature increased in the last century?
About 0.5°C (≈1°F)
List the layers of the atmosphere in order from Earth’s surface to outer space
Troposphere → Stratosphere → Mesosphere → Thermosphere → Exosphere
Define albedo.
The measure of how much solar radiation is reflected by Earth’s surface
Why are most of the world’s deserts found near 30° north and south latitude?
Cool, dry air sinks at 30°, creating dry conditions
Why does warm surface water decrease upwelling?
Warm water is less dense and prevents cold water from rising
Describe the greenhouse effect.
Greenhouse gases absorb outgoing infrared radiation, trapping heat in the troposphere
Which region of Earth is warming the fastest?
The poles
Which layer of the atmosphere has the highest density of gas molecules and why?
Troposphere, because gravity pulls most atmospheric mass toward Earth’s surface
Give one example of a low-albedo surface and one high-albedo surface.
Low: forests or oceans
High: snow, ice, clouds, or sand
Name the three vertical wind circulation cells and their latitudinal ranges.
Hadley (0–30°), Ferrel (30–60°), Polar (60–90°)
Where does El Niño occur and what happens to trade winds?
Eastern Pacific Ocean off South America; trade winds weaken
In which layer do greenhouse gases absorb radiation, and what type is it?
Troposphere; outgoing infrared (IR) radiation
Identify two causes of sea level rise and the primary cause.
Thermal expansion (main cause) and melting land ice
In which layer does the ozone layer exist, and what is its function?
Stratosphere; absorbs harmful ultraviolet (UV) radiation
What effect does a higher albedo have on Earth’s temperature?
More solar energy is reflected, leading to cooler temperatures
Describe the Coriolis effect.
The deflection of winds due to Earth’s rotation; clockwise in the Northern Hemisphere and counterclockwise in the Southern Hemisphere
How does El Niño affect ocean biodiversity and the fishing industry?
Decreased biodiversity and reduced fishing due to reduced nutrients
Name four greenhouse gases (excluding water vapor) and one source for each.
CO₂ (fossil fuels), CH₄ (landfills/cattle), N₂O (fertilizers/vehicles), CFCs (refrigerants)
Define a positive feedback loop and give one polar example.
A change that amplifies itself; melting ice decreases albedo, increasing warming
In which atmospheric layer do auroras occur and what causes them?
Thermosphere; photodissociation and ionization caused by high-energy UV radiation
What is the main cause of Earth’s seasons?
Earth’s 23.5° axial tilt, not distance from the Sun
Explain the rain shadow effect.
Moist air rises on the windward side of mountains, cools and precipitates; dry air descends on the leeward side
Describe La Niña’s effect on surface water temperature and food webs.
Cooler, nutrient-rich waters increase biodiversity and productivity
Why is water vapor not considered a major driver of climate change?
It has a short residence time and cycles naturally through the water cycle
What was the purpose of the Kyoto Protocol?
To reduce global greenhouse gas emissions through international cooperation