GEOG110 Midterm 1 - Matthew Winnick

Steady-state (Equilibrium)

A system or variable that does not change through time. Requires a steady flow of input and output energy.

Positive Feedback Loop

When the output of a stimulus amplifies the initial stimulus.

Negative Feedback Loop

When the output of a stimulus opposes the initial stimulus.

Transient State

When equilibrium/steady-state is temporarily broken.

Electromagnetic Radiation

A type of energy that travels through space as waves.

Visible EM Radiation

The only part of the electromagnetic spectrum that our eyes can detect. The shortest wavelengths.(Think rainbow colors)

Infrared EM Radiation

Wavelengths longer than visible light, so we can't see it, but we can feel it. (Think warmth- when you can feel the heat from the sun)

Ultraviolet EM Radiation

Shorter wavelengths than visible light = holds the most energy (Think getting a sunburn)

Blackbody Radiation

Objects emit electromagnetic waves whose characteristics depend on the object's temperature (Sun and Earth behave like blackbodies)

Planck's Law

Describes how hot objects emit electromagnetic radiation across different wavelengths based on their temperature

Do hot or cold objects give off more energy (shorter wavelengths)?

Hot

What happens when the Earth emits less energy than it absorbs?

It warms up

What happens when the Earth emits more energy than it absorbs?

It cools down

Albedo

The fraction of light reflected by an object

Do oceans or land have higher albedo?

Land, especially ice.

Why is Earth's albedo decreasing?

Glaciers are melting and turning into ocean water, which has a lower albedo overall.

Radiative Balance

Earth's temperature stays stable when the energy coming in from the sun equals the energy leaving the Earth back to space.

What happens if incoming energy > outgoing energy?

The planet warms.

What happens if incoming energy< outgoing energy?

The planet cools.

Stefan-Boltzmann Constant

A number that tells us how much energy an object radiates as heat based on it's temperature.

Greenhouses Gases

Gases in the atmosphere that absorb and re-emit infrared radiation, which traps heat and warms the earth.

How are greenhouse gases able to absorb infrared energy?

They have an asymmetric molecule shape.

What is the most important greenhouse gas and why?

Water vapor, because it has the largest role in the natural greenhouse effect.

Why is carbon dioxide a notable greenhouse gas?

It is the most human-controlled greenhouse gas.

Greenhouse Effect

Gases absorb and re-emit heat that is emitted from the Earth after sunlight warms the Earth.

What happens to the wavelengths that get trapped by the Greenhouse Effect?

They get sent back to Earth.

Why is the Greenhouse Effect so important?

It is essential to life because it keeps the Earth warm enough for liquid water.

Band Saturation

Greenhouse gases absorb infrared radiation at specific wavelength bands

What happens when you add more gas to the Greenhouse Effect?

Total absorption still increases even if the main band is already mostly full, which means more heat is trapped in the atmosphere.

Heat Capacity

How much energy something can absorb before its temperature changes.

High Heat Capacity

Absorbs lots of heat without temperature changing much.

Low Heat Capacity

Heats up and cools down quickly.

Does water have a high or low heat capacity?

Very high. It buffers temperature changes and keeps climates more stable.

Water Triple Point

The temperature and pressure where water can exist simultaneously as ice, liquid, and vapor. Show how water transitions between it's forms.

Sensible Heat

Heat you can feel as the temperature changes.

How is sensible heat transported in the atmosphere?

Transported via conduction, convection, and advection. All directions.

Latent Heat

Energy absorbed or released when a substance changes form without changing its temperature.

How is latent heat transported in the atmosphere?

Transported via rising and moving water vapor. This is how the Earth redistributes energy.

Troposphere

The lowest layer of Earth's atmosphere. Where weather happens and water vapor is stored. It's behavior controls climate and weather.

Convection Cell

A loop of rising warm air and sinking cool air, moving heat and moisture in the atmosphere and driving weather patterns.

What happens to rising air?

Cools and condenses, forming clouds and precipitation.

What happens to sinking air?

Dries and warms.

Coriolis Effect

Earth's rotation making moving air/water bend, which determines the rotation of storms and the path of winds.

What direction does air move in the Northern Hemisphere?

To the right.

What direction does air move in the Southern Hemisphere?

To the left.

What direction do hurricanes rotate in the Northern Hemisphere?

Counterclockwise.

What directions do hurricanes rotate in the Southern Hemisphere?

Clockwise.

Hadley Cells

A tropical atmospheric circulation cell where warm air rises near the equator, moves toward 30° latitude, cools and sinks, creating trade winds and deserts around 30° N/S.

Ferrel Cells

A mid-latitude circulation cell where air moves poleward near the surface and equatorward aloft, connecting Hadley and Polar cells; responsible for westerlies in 30-60° latitudes.

Polar Cells

A polar atmospheric circulation cell where cold air sinks at the poles, flows toward 60° latitude, rises, and returns poleward aloft; drives polar easterlies.

Orographic Precipitation (Rain Shadows)

Mountains make air rise, causing rain on the windward side and dry conditions on the leeward side.

What happens on the windward side of a mountain (Orographic Precipitation)?

Facing the wind causes rain or snow as air cools and condenses

What happens on the leeward side of a mountain (Orographic Precipitation)?

Air descends, creating a rain shadow as air warms and dries.

Surface Ocean

The top layer of the ocean (top 100-200 meters). Makes up 10% of ocean water.

Deep Ocean

The lawyer below the surface ocean, extending to the ocean floor (deepest parts are 11,000 meters). Makes up 90% of ocean water.

How does wind act as a driver of surface ocean currents?

Pushes water up, creating large global currents.

How do tides act as a driver of surface ocean currents?

Pull water with gravitational forces, creating coastal currents.

Eckman Transport / Eckman Spiral

Wind moves the surface water of the ocean, but the Coriolis effect twists the motion with depth, forming the Ekman Spiral.

Ocean Gyres

Giant circular ocean currents driven by wind and Earth's rotation that move heat around the planet.

What are Ocean Gyres caused by?

Wind, the Coriolis effect, and continents blocking water flow.

What direction do Ocean Gyres rotate in the Northern Hemisphere?

Clockwise.

What direction do Ocean Gyres rotate in the Southern Hemisphere?

Counterclockwise.

Upwelling

When deep, cold water rises to the ocean, bringing nutrients that support marine life.

Causes of upwelling along coastlines

Wind blows along the coast, and Ekman transport pushes water away from the shore, causing deep water to rise and replace it.

Causes of upwelling along the equator

Winds blow west, Coriolis effect pushes surface water away from the equator, and deep water rises to replace it.

Downwelling

Surface water sinks to the deep ocean.

What causes downwelling along coasts?

Wind blows along the coast, Ekman transport pushes surface water toward the shore, and water piles along the coast and sinks downwards.

Thermohaline Circulation

Dense water sinks, less dense water rises, creating deep and surface currents.

Pattern of Thermohaline Circulation

Surface water sinks, deep water moves along the ocean floor, deep water rises (upwelling).

Ocean Heat Transport

Moves heat very slowly, mainly though ocean currents.

Atmospheric Heat Transport

Moves a lot of heat quickly, through winds and convection.

El Niño

Trade winds weaken, warm water spread eastward across the Pacific, causing warmer global temperatures.

La Nina

Trade winds strengthen, pushing warm water westward and more cold water upwells in the east, causing cooler global temperatures.

Short-Term Carbon Cycle (days to decades)

Fast carbon moves between air, plants, animals, and surface ocean.

Long-Term (Thousands to millions of years)

Slow carbon moves through rocks, sediments, and deep ocean, controlling climate over millions of years.

Carbon Reservoirs

Where carbon is stored.

Carbon Fluxes

How carbon moves.

Residence Times

How long carbon stays.

Do small carbon reservoirs have a short or long residence time?

Short.

Do big carbon reservoirs have a short or long residence time?

Long.

Photosynthesis

The process by which plants use sunlight to make energy.

Plant Respiration

Plants use some of the sugar they made in photosynthesis for energy, releasing CO2 back into the atmosphere.

Soil Respiration

Microbes break down dead plant material and organic matter in soil, releasing CO2.

Permafrost

Soil or sediment that remains frozen for at least two consecutive years.

Why does permafrost store so much carbon?

Because plant material cannot fully decompose in the cold.

Does cold or warm water hold more CO2?

Cold

Biological Pump for Ocean Carbon

Carbon is physically moved downward via living organisms.

Physical Pump for Ocean Carbon

Carbon is transported by water movement and solubility, not biology.

What happens to CO2 in polar regions?

It gets absorbed and sinks.

What happens to CO2 in warm regions?

It gets released, and these regions become a carbon source.

Calcium Carbonate

Stores carbon in rocks and sediments for millions of years. A major part of the crustal carbon reservoir, helps regulate long-term climate.

Volcanic Emissions

Calcium carbonate -> buried sediments -> subduction -> volcanic CO2

What does the chemical weathering of Silicate Minerals do?

Slowly reduces atmospheric CO2 and helps stabilize Earth's climate over millions of years.

Is Silicate Weathering Feedback positive or negative?

Negative feedback because it opposes the temperature change.

Where does coal come from?

Land plants that have been buried in swamps.

Where does petroleum come from?

Marine plankton and algae, which have been mixed with sediments on the ocean floors.

Stable Carbon Isotopes

Rising atmospheric CO2 is becoming mode C12 heavy, showing the source of carbon is ancient plant material (fossil fuels).

Radioactive Carbon Isotopes

Fossil Fuels are so old that there is no C14 left. If atmospheric CO2 is less, it indicates the source is fossil carbon, not plants.

Ice Cores

Cylinders of ice drilled from glaciers or ice sheets, trap ancient air bubbles and give a direct record of past atmospheric gases.

Tree Rings

Show seasonal growth patterns.