'B' CLIMATES * Areas where the Potential Evaporation > Precipitation ...
'B' CLIMATES * Areas where the Potential Evaporation > Precipitation * Potential Evapotranspiration: the amount of moisture that would evaporate from a given area if it were available * 'B' climates are the only climates based on precipitation ** General characteristics:
* cover 25 - 35% of earth's land area
* precip is quite variable, spatially & temporally Types:
BW: Arid or desert (0-10 inches)
BS: Semi-arid or steppe (10-20 inches)
BWh: Tropical Desert
BSh: Tropical Steppe
BWk: Mid-latitude Desert * 3rd letter: h = hot
&
BSk: Midlatitude Steppe
k = cool to cold
BWh & BSh: Tropical Desert & Tropical Steppe Location: centered on ~ 20° - 30 ° N & S BWh: n Mexico, sw U.S.; Atacama (SA); Sahara, Namib, Kalahari (Africa); Saudi Arabia; central Australian deserts BSh: the Sahel (Africa) Characteristics: very low precip,* * highest T°'s ever recorded on earth (136°F in Libya) Mechanisms: * dominates the STH(sub-tropical high) cells all year BWk & BSk: Mid-latitude Desert & Steppe Location: poleward of BSh & BWh areas; BWk: Great Basin (U.S.); Patagonia(Argentina); Gobi desert area & Takla Makan area (Mongolia/sw China) BSk: Great Plains(U.S.); Turkey to central Asia (Russian Steppe) Characteristics: hot summers, BUT cool to cold winters Mechanisms: * Rainshadow effect: Great Basin & Great Plains. Patagonia, Russian
Steppe, Takla Makan •
remoteness from water sources (continentality): Gobi Desert, Russian Steppe
Review Know locations in North America and mechanisms clouds (main types of clouds) cumulus, stratus, nimbostratus, cirrus, cumulonimbus(thunderstorm) fog know difference and how they form, how ground fog or radiation fog forms, valley fog, advection fog, evaporation fog, steam fog difference between frost (d.p.T° is below 0) and frozen dew Bergeron or icecrystals process Collisioncoalescence process rain; snow; hail global patterns of precipitation (ITCZ, etc) air masses (know abbreviations, characteristics) fronts (hot or cold) midlatitude wave cyclone (stages 3,4,5 and key characteristics; know diagram) stages of a thunderstorm (downdrafts and updrafts, mature stage most dangerous) tornadoes will form with the updraft; hail with the downdraft lightening/thunder mature or dissipating stage lightening stepleader (cant see the lightening et but its coming down) return stroke (returning, can now see lightening as it goes back up) thunder: because of the heat from lightening in air) tornadoes start out horizontal then go vertical peak time of year in U.S = summer (tornadoes) hurricanes peak month for hurricanes in atlantic is septmeber water temperature has to be at least 27°C (81°F) lifespan of hurricanes (810 days) (know stages) locations in North America (key characteristics)
* cover 25 - 35% of earth's land area
* precip is quite variable, spatially & temporally Types:
BW: Arid or desert (0-10 inches)
BS: Semi-arid or steppe (10-20 inches)
BWh: Tropical Desert
BSh: Tropical Steppe
BWk: Mid-latitude Desert * 3rd letter: h = hot
&
BSk: Midlatitude Steppe
k = cool to cold
BWh & BSh: Tropical Desert & Tropical Steppe Location: centered on ~ 20° - 30 ° N & S BWh: n Mexico, sw U.S.; Atacama (SA); Sahara, Namib, Kalahari (Africa); Saudi Arabia; central Australian deserts BSh: the Sahel (Africa) Characteristics: very low precip,* * highest T°'s ever recorded on earth (136°F in Libya) Mechanisms: * dominates the STH(sub-tropical high) cells all year BWk & BSk: Mid-latitude Desert & Steppe Location: poleward of BSh & BWh areas; BWk: Great Basin (U.S.); Patagonia(Argentina); Gobi desert area & Takla Makan area (Mongolia/sw China) BSk: Great Plains(U.S.); Turkey to central Asia (Russian Steppe) Characteristics: hot summers, BUT cool to cold winters Mechanisms: * Rainshadow effect: Great Basin & Great Plains. Patagonia, Russian
Steppe, Takla Makan •
remoteness from water sources (continentality): Gobi Desert, Russian Steppe
Review Know locations in North America and mechanisms clouds (main types of clouds) cumulus, stratus, nimbostratus, cirrus, cumulonimbus(thunderstorm) fog know difference and how they form, how ground fog or radiation fog forms, valley fog, advection fog, evaporation fog, steam fog difference between frost (d.p.T° is below 0) and frozen dew Bergeron or icecrystals process Collisioncoalescence process rain; snow; hail global patterns of precipitation (ITCZ, etc) air masses (know abbreviations, characteristics) fronts (hot or cold) midlatitude wave cyclone (stages 3,4,5 and key characteristics; know diagram) stages of a thunderstorm (downdrafts and updrafts, mature stage most dangerous) tornadoes will form with the updraft; hail with the downdraft lightening/thunder mature or dissipating stage lightening stepleader (cant see the lightening et but its coming down) return stroke (returning, can now see lightening as it goes back up) thunder: because of the heat from lightening in air) tornadoes start out horizontal then go vertical peak time of year in U.S = summer (tornadoes) hurricanes peak month for hurricanes in atlantic is septmeber water temperature has to be at least 27°C (81°F) lifespan of hurricanes (810 days) (know stages) locations in North America (key characteristics)
