Meteorology Exam

• The absolute temperature scale is Kelvin
• The Kelvin temperature of zero represents no molecular motion
• The temperature values for the freezing point of water or the melting point of ice is 32°F, 0°C, and 273K.
• A 5°C change in temperature is the same as a 5K change in temperature.
• A 5°C change in temperature is the same as a 9°F change in temperature.
• Temperature is a direct measure of the mean squared speed of air molecules or the mean kinetic energy of motion. The higher the temperature the faster the molecules are moving
• The change of state of liquid water to water vapor is known as evaporation and from water vapor to liquid water as condensation.
• A water phase change involving condensation (vapor → liquid), deposition (vapor → ice), or freezing (liquid → ice) warms the surroundings.
• A water phase change involving evaporation (liquid →vapor), sublimation (ice → vapor), or melting (ice → liquid) cools the surroundings.
• The heaviest or most massive molecule in a volume of randomly moving and elastically bumping molecules will be moving the slowest or have the most inertia (resistance to movement change).
• The lightest or least massive molecule in a volume of randomly moving and elastically bumping molecules will be moving the fastest or have the least inertia.
• A substance with a large number of independent modes of molecular motion has a large specific heat capacity which means it will change little in temperature when heated.
• A substance with a small number of independent modes of molecular motion has a small specific heat capacity which means it will change greatly in temperature when heated.
• Thermal energy is the total energy of molecular motion within a unit mass or unit volume of matter.
• Temperature is the average energy of molecular motion within a unit mass or unit volume of matter
• The transfer of thermal energy by bulk mass movement is convection.
• The transfer of thermal energy by direct contact is conduction.
• The transfer of energy in the earth-atmosphere affecting thermal energy is through radiation, conduction, convection, and latent heat.
• The sun emits 44% of its radiation in the visible light band where peak radiant intensity also occurs.
• A Blackbody object absorbs and emits radiation at maximum efficiency.
• Kirchhoff’s Radiation Law states good absorbers are good emitters at a particular wavelength.
• The inverse square law for radiation states the amount of radiant energy received from an object emitting radiation decreases as your distance increases (move farther away) from the object.
• The amount of radiation emitted by an object increases as its temperature increases or warms (Stefan-Boltzmann law). This is a direct proportionality, as one increases the other increases.
• The wavelength corresponding to the peak intensity of radiation emitted by a blackbody object decreases or becomes shorter as the object temperature increases or warms (Wien’s Law). This is aninverse proportionality, as one increases the other decreases
• The blue color part of a flame is hotter than the red part because temperature is inversely proportional to peak intensity of radiation and blue light has a shorter wavelength (Wien’s law).
• The more direct the rays of electromagnetic radiation striking a surface the more radiant energy per unit area the surface receives.
• An object absorbing more (less) radiation than it is emitting will warm (cool)
• On the spring and fall equinox 12 hours and 8 minutes of daylight occurs for everyone over the entire earth, except at the poles
• The global energy budget, representing equilibrium conditions, has the absorption of infrared radiation the major energy transfer process warming both the earth's surface and the atmosphere
• Globally, the amount of atmospheric infrared radiation absorbed at the ground is nearly double that of solar radiation
• The thermal energy balance on earth is achieved by eliminating net radiation gains (surpluses) over the tropics and losses (deficits) over the polar regions by heat transport from winds, ocean currents, and latent heat
• The 23.5° tilt of the earth's rotation axis with respect to the earth's orbit plane explains the change in seasons. This orientation of the tilted earth with respect to the sun causes more direct sunlight and longer daylight hours in the summer and less direct sunlight and shorter daylight hours in the winter
• The North Pole receives 6 months of darkness and 6 months of daylight.
• Locations on the equator receive 12 hours of daylight day after day all year
• On a yearly global average, the incoming solar radiation in the outer atmosphere is same as the outgoing earth-atmosphere radiation
• On the winter solstice the northern hemisphere is receiving the least incoming solar radiation while the southern hemisphere is receiving its most.
• On the summer solstice the northern hemisphere is receiving the most incoming solar radiation while the southern hemisphere is receiving its least
• Refraction of sunlight through the earth’s atmosphere gives us an additional 8 minutes of daylight