AOSC FINAL EXAM What was the composition of the early atmosphere Of the atmosphere today Today s Atmosphere Nitrogen N2 78 Oxygen O2 21 Argon AR 93 Trace Gases Carbon Dioxide CO2 Methane Ozone Chlorofluorocarbons Water Vapor Early Atmosphere Hydrogen helium methane and ammonia Volcanic eruptions introduced nitrogen carbon dioxide and water vapor into atmosphere Molecular oxygen introduced from photosynthesis of algae How we got oxygen The oxygen eventually produced the ozone What are the sources and sinks of atmospheric carbon dioxide 5 Sources Volcanic activity Plant and animal respiration Burning of fossil fuels Plant Decay Deforesta tion 3 Sinks Photosynthesis Oceans Carbonates How does the hydrological cycle work and what are the different phases of water oceans Cycle is fueled by solar energy and is a continuous exchange of water btwn land atmosphere Sun heats ocean surface warms evaporates rises as gas and cools starts to condense turns back into liquid water and form a cloud it grows large enough falls out of the cloud as liquid precipita tion Transpiration Evaporation Water leaving the leaves of plants as a gas into the atmosphere condensation transpiration repeat Know the layers of the atmosphere In which layers does the temperature increase with height Decrease with height Tired Sophie May Trip Troposphere Lower layer temp decreases with height Stratosphere Temp increases with height Mesosphere Temperature decreases with height Thermosphere Temperature increases with height What are the 5 main processes of energy transfer How does each work Conduction Transfer of heat through matter from molecule to molecule Air is a poor conductor Convection Transfer of heat through vertical mass movements The match heats air around it it makes it hotter than its surroundings causes it to move up Results in a ver tical atmospheric circulation patterns Advection Horizontal movements in air includes fronts Radiation Energy from sun to eat through electromagnetic waves Latent Heat Heat is released absorbed during phase changes melting evaporation latent heat taken in and freezing condensation latent heat is released Gives us another way of transferring energy to the atmosphere Oceans absorb solar energy to evaporate water vapor Water Vapor is transported by wind Latent heat is the source of energy that drives severe weather How does the intensity of incoming radiation change with latitude Remember this involves the area over which the radiation is spread Seasons have NOTHING to do with the suns distance from the earth NH points away from the sun in the winter less radiation at the surface per unit area NH points towards the sun in the summer more radiation at the surface per unit area Solar zenith angle at the poles is greater than the solar zenith angle at equator larger angle more atmosphere to travel through Poles receive less direct sunlight less radiation per unit area High sun is in the summer moths heats up quicker Seasons occur due to the tilt of the Earth which is tilted at 23 5 degrees Why do the tropics receive an energy surplus and the poles an energy deficit How is heat distributed from the tropics to the poles Average net energy balance energy in vs energy out Incoming radiation outgoing radiation thermal equilibrium At the equator there is a surplus of energy more incoming than outgoing At the poles there is a deficit of energy more outgoing than incoming B C of convection heat is transported from the equator to the poles At what time of day is the temperature the greatest Occurs right before sunset where the sun has been out for the longest period of time Temperature is the greatest at 3 or 4 pm Know the 5 controls of temperature Why do coastal areas have more moderate tem peratures Specific heat of land vs water Latitude The amount of radiation per unit area and length of day Elevation Temperature decreases with height Surface Type Darker surfaces absorb more radiation Cloud Cover Clouds absorb and reflect radiation Ocean Currents Circulate warmer waters towards the poles and cooler towards the equator Land heats faster than water b c water has a higher specific heat Oceans can stabilize temperatures coastal regions have a more stable temp range What is a dry adiabatic lapse rate and how is the moist adiabatic lapse rate differ ent When compared to the surrounding atmosphere s rate of cooling when is the at mosphere absolutely stable and absolutely unstable Dry Adiabatic Lapse Rate When an air parcel becomes warmer than its surroundings it rises expands and cools 10 degrees C km Moist adiabatic Lapse Rate When a saturated parcel condensates releases latent heat and continues to rise it cools at a slower rate 6 degrees C km When DALR ELR its stable air parcel is cooler than its surroundings and falls back towards the ground When DALR ELR it is unstable air parcel is warmer than its surroundings and continues to rise What is a Temperature Inversion Temperature Inversion When temperature increases with height instead of decreases Traps pollutants close to surface Two types Subsidence and radiation Happens sunrise b c cold from night and sunset What do we mean when we say air has reached saturation and how does the satura tion vapor pressure change with temperature How does the saturation vapor pres sure differ between a water droplet and a piece of ice curvature effect Humidity The amount of water vapor in the atmosphere Vapor Pressure The amount of pressure exerted by H20 vapor present in the atmosphere Saturation Vapor Pressure Pressure exerted by H20 vapor when the air is saturated VP and SP both increase when the temperature increases Warmer temps holds more water vapor Higher temp more water vapor high pressure Saturation is achieved when The of water vapor molecules leaving water surface the of returning from the atmosphere to the water surface Curvature Effect On the surface of a water droplet each water molecule is pulled down by fewer neighbor molecules this curvature effect makes it easier for molecules to evaporate from a droplet Block of ice and a drop of water and there is one molecule on each According to the geometry of the shape there is three attached to the droplet and five on the cube There is less molecules above the block of ice be cause it takes slower to saturate What is specific humidity and relative humidity Relative Humidity The amount of water vapor in air divided by amount required for saturation amount of water vapor amount required for