This document describes the global pressure belt system and associated wind patterns. It outlines four main pressure belts: 1) Equatorial low, 2) Subtropical high, 3) Subpolar low, and 4) Polar high. It then discusses the planetary wind systems that arise from these pressure gradients, including the trade winds, westerlies, and polar easterlies. It also covers jet streams, air masses, frontal systems, and cyclones.

1. CLIMATOLOGY L-2

2. PRESSURE SYSTEM OF THE WORLD
 4 BELTS IN THE WORLD

3. EQUITORIAL LOW PRESSURE BELT
ABSENCE OF ADVECTION OF AIR
BELT OF CALM / DOLDRUM
LIGHT FEEBLE WIND

4. SUB TROPICAL HIGH PRESSURE BELT
 AKA HORSE LATITUDE
 THE AIR ABOVE EQUATOR MOVES TOWARDS POLES
BUT THEIR PATH DEFLECTED DUE TO CORIOLIS FORCE
( PATH LENGTH INCREASES), ENERGY REDUCED IN MID
PATH & COOLS DOWN.

5. SUBPOLAR LOW PRESSURE BELT
 COLD WIND FROM POLES MOVES TOWARDS EQUATOR ,
COLLIDE WITH WARM WINDS FROM SUBTROPICAL
HIGH PRESSURE AND WARM WIND RISE UP. THIS
CREATES A LOW PRESSURE.

6. POLAR HIGH
 AIR ARISEN AT SPLP DESCENDS AT POLES WHICH GIVE
RISE TO HIGH PRESSURE CONDITION . THIS HIGH
PRESSURE IS THERMALLY INDUCED.

7. PLANETARY WINDS
 HORIZONTAL WINDS
 PRESSURE BELT SYSTEM PROVIDES THEM THE PRESSURE GRADIENT.
 CORIOLIS FORCE MODIFY THEIR DIRECTION ( WIND BLOWS IN SAME DIRECTION
THROUGHOUT YEAR).

8. TYPE OF WINDS
 TRADE WINDS –MOVE TOWARDS ITCZ , DIRECTION IS EAST
TO WEST DUE TO CORIOLIS FORCE .
 WESTERLIES –FROM WEST TO EAST , FROM STHP TO SPLP.
 0 – 30 DEGREE –TRADE WINDS ( PLACE OF ITCZ ).
 30 – 60 DEGREE – WESTERLIES
 60 – 90 DEGREE – POLAR EASTERLIES
 SEASONAL WINDS – IN WINTER –FROM NORTH TO SOUTH
 - IN SUMMER – FROM SOTH TO NORTH
 LOCAL COLD WINDS IN SIBERIA – BURAN
 LOCAL COLD WINDS IN CANADA - BLIZZARD

9. TYPES OF WIND
UPPER TROPOSPHERIC WINDS
 WIND ACCUMULATED ABOVE EQUATOR AND START
MOVING TOWARDS POLES .
 MOVE UPWARDS TILL TROPOPAUSE ( FACE CORIOLIS
FORCE THERE).
 AKA GEO STRATIC WINDS
 DUE TO LESS FRICTION & HIGH SPEED, THEY ARE VERY
STRONG WINDS .
 THESE WINDS ARE WESTERLIES WINDS.
 ALMOST 90 DEGREE DEFLECTION DUE TO CORIOLIS
FORCE

10. TYPES OF WINDS
 ROOSBY WAVES – MEANDERATION OF
WESTERLIES TO MAINTAIN ANGULAR
MUMENTAM.
 JET STREAMS – AT THE MARGINS OF HEAT
CELLS
 4 PERMANENT- 2 POLAR JET & 2 SUBTROPICAL
WETERLY JET STREAM.
 TEMPORARY JET STREAM AT WESTERN INDIA
FROM EQUATOR IN THE MONTHS OF JUNE –
JULY – AUGUST.

11. OMEGA BLOCK / TRAVELLING DEPRESSION
 JET STREAMS EMBEDDED IN
WESTERLIES CAUSE PRESSURE
VARIABILITY THATSWHY TRAVELLING
DEPRESSISON.
 THE MEETING REGION OF TWO MASSES
IS KNOWN AS FRONT.

12. CONDITIONS OF LOW PRESSURE
THERMALLY INDUCED
 BECAUSE OF HIGH TEMPERATURE
 EX – LOW PRESSURE AT EQUATOR
 CONVENTIONAL RAINFALL AT
EQUATOR.
DYNAMICALLY INDUCED
 UPLIFTMENT OF WARM AIR
 EX – LOW PRESSURE AT SUBPOLAR
LP BELT
 FRONTAL RAINFALL

13. DEVELOPMENT OF FRONTAL CYCLONES
 WHEN AIRMASS MOVES FROM THEIR SOURCE REGION (
WARM AND COLD AIRMASS FACE EACH OTHER ),
FRONT IS CREATED BETWEEN THEM CALLED
STATIONARY FRONT, THEN START CIRCULAR
MOVEMENT.
 COLD AIR MAS PUSHES THE WARM AIRMASS , FORCED
UPLIFTMENT OF AIR , CIRCULAR DUE TO CORIOLIS
FORCE.

14. TYPES OF CYCLONE
EYE OF CLONE – HP , WALL- LP
TEMPERATE CYCLONE
 30 – 40 DEGREE LATITUDE
 DYNAMICALY INDUCED THROUGH
FRONTAL INTERACTION
 WEST TO EAST MOVEMENT IN
LARGE AREAS
 POWERFULL ON LAND
 AFFECT MAINLAND
TROPICAL CYCLONE
 8 – 20 DEGREE LATITUDE
 THERMALLY INDUCED , AIR RISES
ABOVE & CORIOLIS FORCE AFFECTS.
 EAST TO WEST ( SMALL AREAS)
 WEAKER ON LAND
 AFFECT COASTAL AREAS
 REASONS – TROPICAL WARM WATER,
WARM OCEAN CURRENT

15. THUNDERSTORM
 THUNDERSTORMS FORMS CUMULONIMBUS CLOUDS
 THUNDERING & LIGHTNING CLOUDS ACCUMULATES +VE CHARGE AT HIGH &
LOW POSITIONS & - VE CHARGE INBETWEEN.
 TYPES OF THUNDERSTORMS
 THERMAL – LOCALISED INTENSE HEATING OF CLOUDS
 OROGRAPHIC – WHEN WARM MOIST AIR PASSES OVER MOUNTAINS
 COLD FRONT – FORCEFULL UPLIFTMENT OF WARM MOIST AIR

16. TORNADO
 INTENSE LOW PRESSURE SYSTEM
 WHEN TORNADO PASSES OVER A WATERBODY , WATER IS SUCKED UP CALLED
WATER FRONT.
 OCCURS MOSTLY IN TEMPERATE REGIONS ( 20-60 ) DEGREE.

17. POLAR VORTEX
 LARGE SCALE ( 1000 KM SQ) CYCLONE AT POLES IN WINTER.
 DEVELOPS AT UPPER TROPOSPHERE AND STRATOSPHERE.
 DEVELPOPS DUE TO DIFFERENTIAL CREATED BTW EQUATOR AND POLES .
 DEVELOPMENT OF POLAR NIGHT JET STREAMS.
 ROOSBY WAVES CAN DIRUPT THEIR MOVEMENT.

19. OZONE DEPLETION
 INCREASE CHLORINE CONCENTRATION IN WINTERS , OZONE DEPLETION IN
SUMEMR.
 POLAR VORTEX IS WEAK IN NORTERN HEMISPHERE ( ARTIC ) DUE TO OZONE
DEPLETION.
 OZONE DEPLETION AT ARTIC KNOWN AS OZONE DENT.
 OZONE DEPLETION AT ANTARTIC KNOWN AS OZONE HOLE .

20. PRESSURE GRADIENT CELLS
 VERTICAL – HADLEY CELL ( EQUATOR TO TROPIC )& FERREL( TROPIC TO POLES )
 HORIZONTAL – WALKER ( FROM PERU TO AUSTRALIA ) AKA ENSO – EL NINO
SOUTHERN OSCILATAION.
 EL NINO – REVERSAL OF ATMOSPHERIC & OCEANIC ACTIVITIES RESULTING IN
RAINFALL AND DROUGHT.
 LA NINO – INTENSIFICATION OF NATURAL ACTIVITIES.

21. CLIMATIC REGIONS OF THE
WORLD WILL BE COVERED
AFTER INDIAN GEOGRAPHY.