Meteorology Exam 1 (Ch 1,2,3,4)

What does a high percentage of hot colors (red, orange, yellow) in clouds indicate on a satellite map?

The cloud is colder and located at a higher altitude.

What percentage of scenarios would produce rainfall if there’s an '80% chance of rain'?

80 scenarios out of 100 would likely produce rainfall.

How far is Earth from the Sun?

93 million miles.

How long does it take for light to travel from the Sun to Earth?

8 minutes.

What fraction of the Sun's total energy output does Earth intercept?

very small fraction

What are the two most important greenhouse gases?

Water vapor and CO2.

What replaced CFCs according to the Montreal Protocol?

Hydrofluorocarbons (HFCs).

How is ozone thickness measured?

In Dobson Units (DU).

What is the typical thickness of the ozone layer?

300 Dobson Units (DU) or approximately 1/8 inch.

What is said about ozone in the stratosphere compared to the troposphere?

Good in the stratosphere for UV absorption, but bad in the troposphere due to health effects.

What are the dimensions of density?

Density = mass/volume, measured in kg/m³.

What is the average air pressure at sea level?

1013 mb or 1013 hPa.

What is the definition of 'Weather'?

The condition of the atmosphere at any particular time or place.

What is the definition of 'Climate'?

Collection of all possible weather and their likelihoods of occurrence over a long time.

What is the formula for calculating kinetic energy?

Kinetic energy = 1/2mv², where m is mass and v is velocity.

What does Stefan-Boltzmann Law of Radiation state?

The total radiant energy emitted is proportional to the temperature to the fourth power.

What is the unit of energy?

Joules (J).

What is the definition of specific heat capacity?

The amount of energy required to raise the temperature of 1 kg by 1 unit Kelvin.

What is the primary role of the ozone layer?

To absorb UV radiation.

What type of scattering occurs with particles smaller than the wavelength of light?

Rayleigh scattering.

What is the average heat capacity of dry air?

1000 J/(kg·K).

What is the greenhouse effect primarily caused by?

The absorption and emission of infrared radiation by water vapor and CO2.

What is wind shear?

The difference in wind speed and direction at different altitudes.

What is the albedo effect?

The fraction of solar energy reflected back into space by Earth's surface and atmosphere.

How can you determine the wavelength of radiation?

Wavelength = wave speed/frequency.

What is Wien's Law of Displacement?

Hotter bodies emit most radiation at shorter wavelengths.

Dobson Unit (DU)

A unit of measure for ozone layer thickness compressed to sea level pressure, where $1\,\text{DU} = 0.01\,\text{mm}$.

Radiosonde

An instrument package launched twice daily (1 hour before midnight UTC and noon) from 108 sites in the United States to measure air properties.

Weather

The condition of the atmosphere at any particular time or place, characterized by variables such as pressure, temperature, humidity, clouds, precipitation, wind, visibility, and air quality.

Climate

The collection of all possible weather conditions and their likelihoods of occurrence over a long period of time.

Work

The active process of transferring or converting energy from one form to another by applying a force over a distance.

Kinetic Energy

The energy possessed by an object in motion, directly related to its speed and calculated as $\frac{1}{2}mv^2$.

Potential Energy

The energy stored in an object due to its position, represented by work done against gravity ($gh$).

Temperature

The measure of the average kinetic energy of the molecules within a substance.

Absolute Zero ($0\,\text{K}$)

The temperature at which molecular kinetic energy ceases and molecules become stationary.

Specific Heat Capacity

The amount of heat energy required to raise the temperature of $1\,\text{kg}$ of a mass by $1\,\text{K}$.

Latent Heat

Hidden energy absorbed or released by water molecules during a phase change without altering the temperature of the substance.

Sensible Heat

Heat transferrable by conduction or convection that changes the temperature of a substance without causing a phase change.

Conduction

The transfer of heat energy through direct physical contact.

Convection

The transfer of heat energy through the movement of air or buoyant turbulent currents.

Stefan-Boltzmann Law of Radiation

A radiation law stating that the total radiant energy emitted by an object per second is proportional to its absolute temperature raised to the fourth power ($E = \sigma T^4$).

Wien's Law of Displacement

A radiation law stating that hotter objects emit their peak radiation at shorter wavelengths ($\lambda_{\text{max}} = \frac{\text{constant}}{T}$).

Kirchhoff's Law of Radiation

A radiation law stating that at any particular wavelength, a good absorber of radiation is also a good emitter, and a poor absorber is a poor emitter.

Rayleigh Scattering

Selective scattering occurring when particles are much smaller than the wavelength of light (such as air gas molecules), causing shorter wavelengths like blue and violet to scatter most intensely.

Mie Scattering

Scattering occurring when particles are roughly equal in size to the wavelength of light (such as dust or cloud droplets), causing all visible wavelengths to scatter equally and producing white clouds.

Geometric Scattering

Scattering occurring when particles are much larger than the wavelength of light (such as large rain drops), where light reflects or refracts off boundaries independent of wavelength.

Atmospheric Phase Changes Chart

A reference chart categorizing water phase transitions into energy-absorbing processes (melting, evaporation, sublimation) and energy-releasing processes (freezing, condensation, deposition).

Saturation Vapor Pressure Exponential Growth Concept

The thermodynamic property where saturation vapor pressure rises rapidly and nonlinearly as temperature increases, and cooling lowers the saturation threshold prior to condensation.

Sublimation

The phase change of water directly from ice to vapor, which absorbs the greatest amount of energy from the surroundings among phase changes.

Deposition

The phase change of water directly from vapor to ice, which releases the greatest amount of latent energy to the surroundings among phase changes.

Absolute Humidity

The mass of water vapor contained within a fixed volume of air, expressed in $\text{g/m}^3$.

Specific Humidity ($q$)

The mass of water vapor contained in a fixed total mass of moist air, expressed in $\text{g/kg}$.

Mixing Ratio ($r$)

The mass of water vapor contained in a fixed mass of dry air, expressed in $\text{g/kg}$.

Vapor Pressure ($e$)

The partial pressure contributed specifically by the water vapor molecules currently present in the atmosphere, measured in $\text{hPa}$.

Saturation Vapor Pressure ($e_s(T)$)

The partial vapor pressure at dynamic equilibrium for a given temperature $T$, where the rate of evaporation equals the rate of condensation.

Relative Humidity (RH)

The percentage ratio of the actual vapor pressure to the saturation vapor pressure at a given temperature, calculated as $\text{RH} = 100 \times \frac{e}{e_s(T)}$.

Dew Point ($T_d$)

The temperature to which air must be cooled at constant pressure and moisture content to achieve full saturation.

Sling Psychrometer

An instrument equipped with both a dry-bulb and a ventilated wet-bulb thermometer used to determine atmospheric humidity.

Wet-Bulb Temperature ($T_w$)

The temperature measured by a wet, ventilated thermometer cooled by evaporation, which serves as an index for human discomfort and evaporative cooling capacity.