Air Environment1 Air Environment Module 3 Aviation Weather Ted Spitzmiller Planned Flight Air Environment2 Completed Flight Log Air Environment3 4 WEATHER SYSTEMS 1.Air Circulation 2.Weather Elements 3.Moisture & Clouds 4.Weather Systems & Changes Significance of italicsimmediate recall Location in your book (x) Air Environment5 Look for these words Coriolis force Jet stream Radiation Revolution Rotation Autumnal (fall) equinox Winter solstice Vernal (spring ) equinox Summer solstice Air Environment6 Source of Weather Sun heats the earth by radiation (1) Sun Earth 15% absorbed by atmosphere 35 % scattered or reflected 50% absorbed by the Earth Air Environment7 Constant Circulation (3) Heated air rises Heating at equator causes unequal pressure areas Air cooling at poles descends Three distinct patterns separated by jet stream Earth tilt causes movement of polar jet towards south in winter Trade winds doldrums Prevailing westerlies ???? Jetstream Air Environment8 Three distinct patterns separated by jet stream Earth tilt causes movement of polar jet towards south in winter Air Environment9 Earths Seasons Varies Circulation (3) Earths Axis tilted 23.5 degrees Seasons dependent on (Spring/Summer/Fall/Winter) Days and nights of equal length on spring and fall equinox Mean distance from Earth to Sun. 149,597,870,691 km or 10^6 mi (93 million miles) 91 million miles during the Northern Hemisphere winter 94.5 million miles during Northern Hemisphere summer, ii Equator rays Sun Equator rays Air Environment10 Earths Atmosphere Ionosphere >100k Stratosphere > 35k Troposphere < 35k (lower in winter) weather 29.92 generally good WX descending and warming Air Environment15 Wind Pressure gradients Local wind systems Land and sea breezes Mountain breezes The Beaufort Scale can be used on land or sea and is used for estimating wind velocity (10) Air Environment16 Beaufort Scale Air Environment17 Reporting Surface Weather-Chart Air Environment18 Air Environment = High Pressure Pattern Air Environment20 Low Pressure Pattern = Air Environment21 Atmospheric Circulation Around Pressure Systems Earths rotation Equatorial 1000 mph, poles 0 mph Coriolis and surface friction effect deflects air to right (record) An object in northern hemisphere is deflected to the right by coriolis force Cyclonic vs anticyclonic (counterclockwise and clockwise) Air Environment22 Pressure Variations Trough elongated low extending from central low Ridge elongated high usually extending from central high Air Environment23 Air Environment24 Temperature (12) Heat is the total energy of all molecules within a substance (12) Water boils at 212 F (100 C ) and freezes at 32 F (0 C) (12) Absolute zero 459 degrees F, or -273 C, or 0 Kelvin Standard 59 sea level ( hg F = (1.8 x C) +32 C = (F/1.8 ) 32 F = 9/5 C +32 What is the F equiv of 15 C STD lapse rate 3 degrees F per 1000 feet (unsaturated air) (2 C) Temp and wind produce a wind chill factor (10) 9 * 15 = 135 = = 59 5 1 5 Air Environment25 Air Environment26 Air Environment27 Moisture and Clouds 3 (19) Condensation Dew point Fog Precipitation Saturation Relative humidity Air Environment28 Moisture Humidity (19) Relative humidity % capable of holding (example...) Air holding all the moisture it can is said to be saturated (19) Dew point given pressure air must be cooled to become saturated (19) Example bathroom shower Saturation affects stability of air Air Environment29 Air Environment30 Clouds (20) Visible moisture condensed on dust Hygroscopic nucleii Classifications Stratiform cool, dry, stable, smooth, poor visibility, drizzle Cumuliform moist, warm, unstable, turbulent, good visibility, rain Cirrusvery high thin wispy clouds Air Environment31 Air Environment32 Fog (19) Radiation Advection Upslope Evaporative Air Environment33 Weather Systems and Changes 4 (27) air mass front hurricane thunderstorm tornado Air Environment34 Air Mass Characteristics - Temp Pressure Moisture (27) Air Environment35 Air Environment36 Air Environment37 Atmospheric Stability Air tends to flow horizontally May be displaced lifted Terrain Thermals Air mass differences Lapse rate and saturation determines stability unsaturated = normally stable saturated and cool = normally stable saturated and warm = normally unstable Stable air resists displacement Unstable air readily moves vertically Air Environment38 Air Environment39 Fronts (28) Air Environment40 Cold Front (28) Cumulus clouds, local heavy rain, good visibility Air Environment41 Warm Front Stratified clouds, steady rain, low visibility Air Environment42 Air Environment43 Frontal characteristics Cold fast/slow, cumulus, good visibility Warm slow, status, poor visibility Stationary Occluded Frontal passage wind shift Air Environment44 Air Environment45 Air Environment46 Air Environment47 Air Environment48 Air Environment49 Cirro-Stratus Air Environment50 Air Environment51 Air Environment52 Thunderstorms (29) Air mass & frontal Requirements Lifting Moisture Unstable air Stages (29) Cumulus building Mature Dissipation Air Environment53 Air Environment54 Air Environment55 Air Environment56 Air Environment57 Tornados (30) Precautions (31) GO to a basement Stay away from windows Air Environment58 Mountain Waves Lenticular Lee side turbulence Air Environment59 Air Environment60 Air Environment61 Jetstream Air Environment62 Air Environment63 Icing Rime clear Air Environment64 Turbulence Light Moderate Severe Tracking Your Weather Record temperature, wind direction and velocity pressure Same time every day Seven consecutive daysAir Environment65 Air Environment66 F, MPH, mbars Air Environment67 Charting your own weather Air Environment68 Lapse rate Adiabatic lapse rate nonstandardinversion Temp changes take place without adding or removing heat from outside the parcel or air Dry adiabatic lapse rate is the cooling of unsaturated air at 5 1/2 per l000 increase in altitude Moist adiabatic lapse rate varies from 2 to 5 degrees. If greater than std lapse rate air keeps rising unstable Less than std inhibits rising stable stagnate poor vis Air Environment69 Air Environment70 CumulusStratus MoistureHeavy Localized RainLight to moderate Wide Spread VisibilityGoodPoor TurbulenceYesNo