1. Define specific heat. What is the significance of a change of state with respect to specific heat?
-specific heat: heat required to raise the temp of 1g of substance 1°C
-latent heat: amount of energy in the form of heat released or absorbed by a substance during a change of phase
-change of phase: when any substance undergoes a change of state, heat is either absorbed or released & you can add heat without raising its temperature 2. Define humidity, saturation, mixing ratio and relative humidity
-Humidity: The amount of water vapor in the air. Humidity is measured in two ways: (1) Absolute humidity is the percentage of water vapor actually present in the air. (2) Relative humidity is the absolute humidity divided by the amount of water that could be present in the air. Relative humidity indicates the degree of comfort or discomfort one feels from the humidity, because it indicates the amount of perspiration that can evaporate from the skin
-Saturation: air holding the maximum amount of water (100% humidity)
-Mixing Ratio: humidity not affected by changes in temp, only the amount of water in air
-Relative Humidity: the ratio of the air’s water vapor content compared with amount of H2O vapor required for saturation at that temperature
3. What are the two ways to change the relative humidity?
-pressure & temperature
4. Define adiabatic cooling.
Adiabatic cooling happens as air mass expands with increasing elevation (because density of gases decreases farther into the atmosphere). As elevation increases, the air gets cooler because energy is drawn from the surroundings. Less dense air traps less heat resulting in this net cooling called adiabatic cooling. It occurs at an average of 6 degrees Celsius per 1000 meters, but it can vary.
5. Why is there a wet and dry adiabatic rate?
-Because in dry adiabatic rate parcel of air rises & expands, then cools, but in wet adiabatic rate at certain altitude
What are the four processes that lift air? Which of these processes is common in Florida?
-orographic uplifting
-frontal wedging
-Convergance
-localized convective uplifiting
6. Define: absolute stability, absolute instability, conditional instability.
-absolute stability: when environmental lapse rate is less than wet adiabatic rate
-absolute instability: when environmental Lapse rate greater than dry adiabatic rate
-conditional instability: when moist air has an environmental Lapse rate between the wet & dry adiabatic rat
7. What role does the stability of air play in determining what sort of weather is occurring at a given time and place?
-Stable air is air that resists vertical movement
8. Describe and name the different types of clouds (your description should include what they generally look like and their altitude.)
-CIRRUS: high white, and thin. They come in patches, sheets, & featherlike fibers
-high altitude: above 6000m (most clouds at this level made of ice, not H2O)
-Cirrocumulus: small puffy blobs
-Cirrostratus: thick clouds in flat layers
-CUMULUS: globular/puffy individual masses. Look like cauliflower, sometimes have flat base
-mid altitude: 2000-6000m
-altocumulus: larger, puffier cumulus clouds
-altostratus: large, dense, & cover most of the sky; white-gray in color; sometimes makes rain or snow
-STRATUS: sheets or layers that cover most of the sky
-low altitude: 0-2000m
-Stratocumulus: stratus clouds that develop globular texture
-Nimbostratus: dark, wide-spread clouds that form when stable air is forced aloft; good rain producers
-CLOUDS OF VERTICAL DEVELOPMENT: cumulonimbus clouds that form when unstable air is forced up; frequently develop thunderstorms & are very dangerous to aircraft
9. What sort of weather do you expect to see associated with cumulonimbus and nimbostratus clouds?
-Stormy & rainy, perhaps snowy
10. Explain the two processes that form precipitation.
-Bergeron Process:
-supercooling: H2O that is below freezing (0*C), but not ice is supercooled b/c freezing nuclei need crystal structure similar to ice & that is rare
-Supersaturation: when air saturated w/ water it is supersaturated w. respect ot ice; ice can’t coexist w/ water so water droplets attracted to ice, freeze, & ice eventually falls
-Precipitation:
-Collision-coalescence: must be some droplets greater than 20 micrometers for this to happen
-needs large condense. Nuclei or hygroscopic particles
-these start to fall & they hit and absorb other water particles on the way down
-the biggest a H2O droplet can get is 5 mm
11. Describe the different process that can create fog
-advection fog: forms when warm moist air moves over cool surface
-radiation fog: forms when earth’s surface cools; tends to collect in low areas
upslope fog: forms when humid air moves up slope & cools
12. What are the moisture and temperature properties of the different air masses (mP, mT, cP, cT)?
-mP: maritime polar: originates over water in high latitudes
-mT: maritime tropical: over water in low altitudes
-cP: continental polar: over land in high altitudes
-cT: continental tropical: over land in low latitudes
13. What air masses affect what parts of the country?
-cP & mT: influence major US weather pattern, especially east of Rockies
-cP air from Canada: source of many cold fronts
-mT: air from Gulf of Mexico very warm, moist & unstable & makes precipitation in E US
-cT rarely moves as an air mass
-mP air responsible for rainy weather in Seattle area on W coast
-mP air on E coast brings severe cold & storms
14. Explain what weather conditions and cloud types are associated with warm and cold and occluded fronts
-Warm:
-Warm air moves into a area formerly occupied by cold air.
-Frequently it rides up over the cold air producing a particular set of clouds: cirrus. cirrostratus, altostratus, nimbostratus
-Produces light rain over large areas before the front actually gets to you
-Cold:
-Cold air moving into an area occupied by warmer air
-Generally produces heavy rain after the front passes
-Occluded:
-A cold front overtakes a warm front
-Generally produce very unpredictable but nasty weather
15. Explain the life cycle of a mid latitude cyclone and what weather patterns are associated with it.
-Begins with a stationary front in the American northwest.
-Flow along this boundary creates a wave.
-This wave develops into a low pressure area and flow is initiated around it.
-As flow develops, the stationary front becomes a warm and cold front.
-The cold front moves faster than the warm front, eventually an occluded front develops and the cyclone dissipates.
