ATMO 336 1st EditionExam # 2 Study Guide Lectures: 1 - 12Lecture 1 - gas pressure (force/area) exerted by water vapor molecules alone. Higher the water vapor molecules (number density), higher the vapor pressure (higher vapor pressure= greater amount of water vapor in air)- rate of evaporation= number of water molecules that change phase from liquid to gas each sec. set by temp of liquid water. (higher temp= higher rate of evaporation)- rate of condensation= number of water vapor molecules that change phase from gas to liquid each sec.( depends on vapor pressure above liquid surface). @ 20 degrees C, condensation=0.- Dynamic equilibrium reached in closed system when rate of evaporation= rate of condensation. This is called saturation vapor pressure (air saturated with water). Water boils= saturation vapor pressure equal the surrounding air parcel.- As air rises and cools, saturation vapor pressure decreases= condensation (cloud formation)-- greater the mixing ration, the more water vapor that is in the air--- dew point temp= temp to which air parcel would have to be cooled (with no change in its water vapor content) in order for it to be saturated with water vapor. As mixing ratio increases, dew point temp. decreases.- The difference between air temperature and dew point temperature indicate whether relative humidity is low or higho 1. When the air and the dew point temp are far apart= relative humidity is lowo 2. When the air and dew point temp are close to same value= relative humidity is higho 3. When the air and dew point temps are same= the air is saturated and the relative humidity is 100%- @ earth’s surface, relative humidity is LESS than 100% (evaporation is faster than rate of condensation)Lecture 2 - If RH= 100% (Td=T), there will be no net evaporation or condensation since the rate of evaporation is equal to the rate of condensation- If RH<100% (Td<T) any liquid water present will evaporate with time, since the rate of evaporation is greater than the rate of condensation- If RH>100% (Td>T) water vapor will condense to liquid water until RH falls back to 100%, since the rate of condensation is greater than the rate of evaporation. When this occurs, it is only a temporary situation until sufficient water vapor condenses out of the air- Energy transfero Energy added= to energy out, temp stays constanto If energy added> energy out, temp of object increaseso If energy added< energy out, temp of object decreases- Radiation= transmission of energy through space or through material medium in form of electromagnetic waves. Hotter the object, the greater the amount of radiation it emits- Conduction= transfer of energy by direct collisions of molecules. o Heat conductivity= rate at which energy is transferred within material. Water and metalsgood conductors. Higher the heat conductivity, the faster heat flows through material through conductiono Rate of conduction heat depends on temp. difference between two objects (larger the difference, the faster the heat transfer) and conductivity of material- Convection= transfer of heat by actual movement of mass within fluid. Moist convection important in atmosphere. Only in liquids and gaseso Dry convection= natural dry convections (warm air rising and cold air sinking) ie. Thermals. Forced dry convection= winds stir up air and forces air to mix which transfers heat or energy from warmer to colder regions.o Moist convection=energy removed due to evaporation of water .water vapor contains more internal energy than watero Rate of heat loss via evaporation depends on net ratio of evaporation, which depends on relative humidity and wind. (fasterwindspeed= faster net evaporation)o Vapor pressure deficit= saturation vapor pressure minus the vapor pressure in the airLecture 3- Thermoregulation= process when human body regulates internal heat generation and external heat exchange so that core temp varies no more than 2 degrees C from its average of 37 degrees C.o Thermal neutral zone= air temp between 20 degrees C and 25 degrees C (66-77 F) w/ little wind and moderate relative humidity- Homeostasis= stable operation of psyciological activities. Over half of all energy from food and other sources leave body as heat. Enzyme and biological reactions most efficient at 98 degrees F.- Vasoconstriction= constricted blood vessels which reduces blood and heat flowand reduces surface area of warm blood that is in contact with outside air- Vasodilatation= widening of blood vessels If air temp is warmer than body temp.- heat index= take into account the decreasing rate of heat loss due to the combination of high temperature and high humidity. Higher heat index= slower rate of heat loss from average human body- wind chill index= dangerous combination of cold and high winds. Lower wind chill index=faster the rate of heat loss from human body.- Cloud=important regulators of earths climate. Formation= vast quantities of heat released from net condensation. As air cools and relative humidity increases since saturation mixing ratio decreases as temperature decreases. o @ relative humidity= 100%, condensation occurs and cloud formation occurs dueto latent heat released (warmer air surrounded by cooler air which makes cloud buoyant since it weighs less than the air and accelerates upward)- rising parcels of air cool since air pressure surrounding the parcel is different than the airpressure inside the parcel which makes the parcels surface unbalanced and its is forced to change in volume.o Air pressure greater outside than inside= parcel is compressed. This is when the air parcel move upward, and the air temp in parcel decreases.o Air pressure less outside than inside, parcel will expand= number density of air parcel decreases. This when the air parcel moves down and the air temp in parcel increases.Lecture 4- Rising air cools and expands to match surrounding pressure. - Conditions for cloud formation. 4 basic mechanisms that force air to move upwardo 1. Surface heating and free convection (thermals formed when hot air rises until it reaches saturation point where water vapor condenses and becomes a cloud)o 2. Horizontal convergence of surface air and/or horizontal divergence of the top of the troposphere (dynamic lifting= rising air is forced due to the dynamics of movement of pattern of horizontal inflow)o 3. Topography (mountains). Wind ward sides have more weather and moister conditions than leeward sides (ie. The rain shadow effect)o 4. Uplift along