mitra quiz 2

Troposphere

Closest to Earth, weather occurs here, temp decreases with height.

Stratosphere

Contains the ozone layer, temp increases with height.

Mesosphere

Coldest layer, meteors burn up.

Thermosphere

Absorbs solar radiation, very hot, auroras.

Exosphere

Outermost layer, merges with space.

Mesosphere (coldest portion)

As low as −90°C.

Troposphere (weather layer)

Weather occurs in this layer.

Pauses

Tropopause, stratopause, mesopause, thermopause separate each layer.

Atmospheric pressure

Pressure = weight of air above; decreases with altitude due to fewer air molecules higher up.

Natural sources of pollutants

Examples include volcanoes (ash, sulfur dioxide), wildfires (carbon monoxide, particulates), dust storms (particulates), and plants (pollen, hydrocarbons).

Anthropogenic sources of pollutants

Examples include cars/factories (carbon monoxide, nitrogen oxides), power plants (sulfur dioxide), aerosols (CFCs), and fossil fuel burning (CO₂, particulates).

Constant gases

Stable gases like Nitrogen (78%) and Oxygen (21%).

Variable gases

Change by time/place, examples include Water vapor, CO₂, Ozone, Methane.

Chlorofluorocarbons (CFCs)

Synthetic chemicals (aerosols, refrigerants) that destroy ozone and increase UV radiation.

Good ozone

Located in the stratosphere, blocks UV radiation.

Bad ozone

Located in the troposphere, a pollutant that harms lungs and crops.

Transmission of energy

Energy passing through the atmosphere unchanged.

Scattering

Deflection of solar energy by particles; includes Rayleigh (tiny molecules, scatters short wavelengths) and Mie (larger particles, scatters all wavelengths).

Refraction

Bending of light when it passes through different mediums.

Reflection

Energy bounced back without absorption.

Albedo

Reflectivity of a surface; high (snow, ice) leads to cooler temperatures, low (asphalt, forest) leads to warmer temperatures.

Absorption

Energy absorbed by surface/gases raises the temperature of the absorber.

Radiation received and emitted by Earth

Receives shortwave (sunlight) and emits longwave infrared (heat).

Impact of clouds on temperature

During the day, clouds reflect sunlight leading to cooler temperatures; at night, they trap heat leading to warmer temperatures.

Greenhouse effect

Natural warming caused by gases (CO₂, H₂O, methane) trapping heat.

Counterradiation

Atmosphere re-radiates absorbed infrared back to Earth.

Light-colored vs. dark-colored aerosols

Light aerosols (sulfates) reflect and cause cooling.

Light aerosols (sulfates)

Reflect, cooling.

Dark aerosols (soot)

Absorb, warming.

Peak daily temperature

A few hours after noon (3-4 PM). Called temperature lag.

Net radiation

Balance between incoming shortwave and outgoing longwave.

Four ways heat is transferred

Radiation (waves), Conduction (molecule contact), Convection (vertical movement), Advection (horizontal movement, wind).

Sensible heat

Heat felt and measured directly as temperature.

Latent heat

Hidden heat stored in water during phase changes (evaporation, condensation).

Specific heat

Energy needed to raise 1 g by 1°C. Water: high specific heat → heats/cools slowly. Land: low specific heat → heats/cools quickly.

Three temperature scales

Celsius: 0° freeze, 100° boil. Fahrenheit: 32° freeze, 212° boil. Kelvin: absolute zero (0 K).

Stevenson Screen

White box with slats for airflow. Protects thermometers from sunlight/precipitation.

Four controls on Earth's temperature patterns

Latitude → sun angle/day length. Altitude → higher = cooler. Cloud cover → moderates temps. Land-water heating differences → oceans heat/cool slower than land.

Maritime vs. continental temperature patterns

Maritime (coastal): mild, small temp range. Continental (inland): extreme, large temp range.

Isotherm

Line on a map connecting equal temps.

Thermal equator

Line of highest average temps. Moves with Sun's seasonal position.

Human impacts on energy balance

Greenhouse gases → warming. Aerosols/land use → change reflection/absorption.

Cold snap

Sudden very cold period.

Heat wave

Prolonged very hot period.

Wind chill

Perceived cold due to wind. Factors: temperature + wind speed.

Heat index

Perceived heat due to humidity. Factors: temperature + humidity.

Basis for dividing the atmosphere into layers

Changes in temperature trends with altitude.

Density as altitude increases

Density decreases → fewer air molecules higher up.

Seasonal variation in incoming shortwave radiation

High latitudes (closer to poles).

Net radiation deficit

High latitudes → lose more longwave than they gain shortwave.

Net radiation surplus

Tropics → receive more shortwave than they lose longwave.

Energy deficit in Deadhorse, Alaska

Sun angle is very low → energy spread out. More energy lost as longwave than gained as shortwave.

Relationship between temperature, density, and pressure

Higher temperature → lower density (air expands). Lower density → lower pressure.

Forces responsible for ocean currents

Surface currents: wind, Coriolis effect, friction. Deep currents: density differences from temp + salinity (thermohaline circulation).