Topic 5- Solar Energy, Atmosphere, and Global Temp.

Vocabulary flashcards covering key terms from the lecture notes on solar energy, atmospheric heating, and global temperatures.

Electromagnetic Spectrum

Range of all wavelengths of energy emitted by the Sun and stars; includes visible light, infrared, ultraviolet, and other wavelengths.

Wavelength

The distance between two successive crests (or troughs) of a wave.

Short Wavelengths

Higher-energy end of the spectrum; generally more damaging to organic material than long wavelengths (e.g., gamma rays are short; infrared is long).

Long Wavelengths (Infrared)

Lower-energy end of the spectrum; infrared radiation is longwave and tends to warm objects rather than cause rapid damage.

Incoming Solar Radiation (Insolation)

Solar radiation reaching Earth; mainly shortwave radiation (visible, some IR, UV); UV can be hazardous.

Outgoing Thermal Radiation

Earth-emitted longwave infrared radiation sent back toward space.

Sub-solar Point

Location on Earth's surface where solar rays strike perpendicular; hottest zone near the Tropics (around 23.5°N to 23.5°S).

Insolation Pattern Across Earth

Variation of incoming solar radiation with latitude and season due to Earth's curvature.

Curvature of Earth

Spherical shape causes solar energy to be spread over larger areas at higher latitudes, influencing temperature differences.

Scattering (Diffuse Radiation)

Downward component of light scattered in all directions; can reach the ground without forming shadows; clouds don’t completely prevent UV exposure.

Diffuse Radiation

Downward, scattered solar radiation coming from many directions.

Refraction

Bending of light as it passes between media of different densities; changes speed and direction of insolation

Mirages

Optical phenomena caused by refraction of light in layers of air with different densities.

Rainbows

Optical effect caused by refraction and reflection of light in water droplets.

Reflection

Return of solar radiation from a surface; part of energy that does not get absorbed.

Albedo

Fraction of incoming solar energy reflected by a surface (0%–100%); high on bright surfaces (snow/ice), low on dark surfaces (rock, asphalt); can change with seasons, weather, and surface type.

Positive Feedback

A process that amplifies an initial change (e.g., ice melt lowers albedo, increasing absorption and warming).

Negative Feedback

A process that dampens or counteracts an initial change (stabilizing effect).

Absorption

Insolation not scattered or reflected is absorbed, warming the surface.

Conduction

Transfer of heat through direct contact between substances.

Convection

Vertical heat transfer via moving air (warmer rising, cooler sinking), creating convection currents.

Advection

Horizontal transport of heat by wind or ocean currents.

Greenhouse Effect

Shortwave solar radiation heats the surface; the surface emits longwave radiation, which is partly trapped by greenhouse gases (CO2, H2O, oxides, CFCs), warming the lower atmosphere.

Greenhouse Gases

Gases such as CO2, water vapor, various oxides, and CFCs that trap longwave radiation and contribute to warming.

Energy Balance

Balance between incoming solar energy and energy emitted to space; about 69% of incoming energy is emitted to space, ~31% is reflected (albedo), totaling 100%.

Direct Warming

Direct heating of the surface by absorbed solar energy.

Indirect Warming

Warming from energy transported and redistributed by atmospheric/oceanic processes.

Water's Specific Heat

Amount of energy required to raise 1 gram of water by 10°C (high specific heat); water absorbs a lot of energy with little temperature change, stabilizing temperatures and protecting aquatic life.

Latitude (Insolation Directness)

The angle of solar insolation; more direct angles (closer to the equator) yield hotter temperatures.

Altitude/Elevation

Height above sea level; higher elevations have fewer air molecules, less energy absorption, and cooler temperatures.

Cloud Cover

Cloud type, height, and density affect absorption and reflection; clouds can warm at night by re-radiating longwave energy and cool during the day by reflecting insolation.

Land vs. Water (Continental vs Marine)

Water moderates temperatures and supports more even climates; land heats up and cools down faster, with evaporation providing cooling.

Evaporation

Liquid water turning to water vapor, absorbing latent heat and cooling the surroundings; more evaporation over water than land.

Marine vs Continental Conditions

Coastal (maritime) climates are more moderate; inland (continental) climates experience larger temperature swings.

Hemispheric Temperature Differences

Differences between hemispheres driven by land vs. sea distribution; the southern hemisphere often warmer in winter due to more water; the northern hemisphere heats more in summer due to more land.

Urban Heat Island

Urban areas become warmer than surrounding rural areas due to dark surfaces, reduced evaporation, and altered energy balance.

Albedo Change Triggers

Global warming, seasons, urbanization, and deforestation can alter surface reflectivity, creating feedback effects.

Contrails and Cirrus Clouds

Aerosol and cloud formations that affect atmospheric temperature and radiative balance.