WEATHER & BIOMESWHAT MAKES A BIOME THAT BIOME?

CLIMATE

• MOST IMPORTANT FACTORS ARE AIR TEMPERATURE & PRECIPITATION

• THE CHARACTERISTIC CONDITION OF THE ATMOSPHERE NEAR THE EARTH’S SURFACE

• THE LONG TERM WEATHER (30 YEARS MINIMUM)

• REGION’S GENERAL PATTERN OF WEATHER CONDITIONS,

• HURRICANES

• DROUGHTS

• RAINY PERIODS

CLIMATE SYSTEM

• BASED ON LOCATION OF HOT AND COLD AIR MASS REGIONS

• ATMOSPHERIC CIRCULATION CREATED BY TRADE WINDS & WESTERLIES

CONVECTION CELLS

• DISTRIBUTE HEAT & MOISTURE

• 6 VERTICAL CURRENTS AT DIFFERENT LATITUDES :

• HADLEY CELL – 0 – 30 - TRADEWINDS

• FERREL CELL – 30-60- WESTERLIES

• POLAR CELL- 60 – 90 - EASTERLIES

Figure 5-6

CORIOLIS EFFECT

• DEFLECTION OF AIR DUE TO THE ROTATION OF THE EARTH & FRICTION BETWEEN AIR & EARTH – LESS EFFECT NEAR THE EQUATOR (FEWER HURRICANES WITHIN 5 DEGREES)

Figure 5-4

TRADE WINDS

• NORTH OF THE EQUATOR BLOW FROM THE NORTHEAST

• SOUTH OF THE EQUATOR BLOW FROM THE SOUTHEAST

• MEET NEAR EQUATOR, CAUSING AIR TO RISE

• AS RISING AIR COOLS, CLOUDS AND RAIN DEVELOP

• RESULTING BANDS OF CLOUDY AND RAINY WEATHER NEAR EQUATOR CAUSE TROPICAL CONDITIONS

WESTERLIES

• BLOW FROM THE SOUTHWEST IN NORTHERN HEMISPHERE

• BLOW FROM THE NORTHWEST IN THE SOUTHERN HEMISPHERE

• SHEER STORMS FROM WEST TO EAST ACROSS MIDDLE LATITUDES

30 DEGREE LATITUDE BELT

• WESTERLIES AND TRADE WINDS BLOW AWAY FROM THE 30 DEGREE LATITUDE BELT

• SURFACE WINDS ARE LIGHT OVER LARGE AREAS CENTERED AT 30 DEGREES LATITUDE

• AIR SLOWLY DESCENDS TO REPLACE THE AIR THAT BLOWS AWAY

• ANY MOISTURE THAT AIR CONTAINS EVAPORATES IN THE INTENSE HEAT

• THE TROPICAL DESERTS, SAHARA & SONORAN, EXIST UNDER THESE REGIONS

THREE BASIC CLIMATE GROUPS GROUP I

• LOW LATITUDE CLIMATES – CONTROLLED BY EQUATORIAL TROPICAL AIR MASSES

• TROPICAL MOIST CLIMATES – RAINFOREST

• WET-DRY TROPICAL CLIMATES – SAVANNA

• DRY TROPICAL CLIMATE – DESERT BIOME (DRY ARID DESERT)

GROUP II

• MID-LATITUDE CLIMATES – AFFECTED BY 2 DIFFERENT AIR MASSES

• TROPICAL AIR MASSES MOVING TOWARD THE POLES

• POLAR AIR MASSES MOVING TOWARDS THE EQUATOR

GROUP II

• DRY MIDALTITUDE CLIMATES – STEPPE LOW GRASS PRAIRIE (INTERIOR REGIONS OF NORTH AMERICA & EURASIAN CONTINENTS)

• MEDITERRANEAN CLIMATE – CHAPARRAL BIOME – WET WINTER, DRY SUMMER CLIMATE

• DRY MIDALTITUDE CLIMATES – GRASSLANDS BIOME – INTERIORS OF NORTH AMERICA & EURASIA (COLD WINTERS, SUMMERS WARM TO HOT)

• MOIST CONTINENTAL CLIMATE – DECIDUOUS FOREST BIOME – POLAR FRONT ZONE & TROPICAL AIR MASSES; SEASONAL CHANGES VERY DIFFERENT BETWEEN WINTER & SUMMER

GROUP III

• HIGH LATITUDE CLIMATES – POLAR AND ARCTIC AIR MASSESS DOMINATE

• BOREAL FOREST CLIMATE (BIOME) (TAIGA, CONIFEROUS)

• TUNDRA CLIMATE (BIOME)

• HIGHLAND CLIMATE – (ALPINE BIOME)