Skip to main content

CYCLONES

Temperate Cyclone


Q.Compare the origin and weather conditions associated with the tropical and temperate   cyclones. (15/16)
Q.Compare and contrast tropical cyclone and temperate cyclone. (12/12)
 
  • Temperate cyclones are low pressure meteorological system which develops in mid latitudes due to convergence of cold air mass and warm air mass.
  • Norwegian scientist Jacob Bjerknes is attributed to giving elaborate theory on temperate cyclone which is known as polar front theory.
  • Polar front theory
    1.Stage I: incipient stage (dilatory motion,stationary front)
    2.Stage II:Frontogenesis stage(cold & warm front,Rossby waves)
    3.Stage III:Mature stage
    4.Stage IV occlusion stage
    5.Stage V Dissipation stage.
  • weather
    1.cold sector
    2.Warm front
    3.warm sector
    4.Cold front

Tropical Cyclone

Low Pressure meteorological system

CONDITIONS
  • Sea surface temperature (> 27 degree cent , so April -Sept.)
  • Coriolis force not less than a minimum value ( so, rarely between 5 N and 5 S)
  • upper air anti cyclogenesis.
  • A Minimum vertical wind shear required,so difficult in sub tropical high pressure zone i.e 30-35 degree latitudes.
  • Pre-existing vortices
  • Sufficient Wind Velocity to move on sea surface


STAGE
1.Stage1 (Incipient stage)
  • Air starts to move in circular motion;isobars away from centers are ill defined;these vortices moves into ITCZ  where intense convection takes place and incipient cyclone develops; core develops which act as zone of convergence.

2.Stage 2(Infantile stage)
  • Eye and eyewall develops;in the upper layer thunder and lightning due to development of cumulonimbus clouds
3.Stage 3(Juvenile stage)
  • Eye,eyewall are developed and rings are in the stage of formation;convection system become prominent and vertical clouds (cumulonimbus) are fully developed;now cyclone can be traced moving over sea and they become   predictable.

4.Stage 4(Mature stage)
  • Eye, eyewall ,inner ring and outer rings are fully developed; clouds are fully developed with nimbo-stratus at lower level and cumulonimbus in the upper layer while cirrus below the tropopause. characterized by high velocity winds over 120 km/hr, thunder and lightning with heavy downpour.

5.Stage 5(Dissipient stage)
  • As they reach ground  , they dissipate as favourable conditions of water vapour not available; Also dissipate as they reach subtropical high pressure belts.




VERTICAL STRUCTURE
1.Eye:
  • Diameter: 2 to 5 Km, Calm Zone, clear sky with bright sunshine, no rainfall, air subsidence;
2.Eye wall:
  • Diameter 20 times the Eye- 30-40 Km; very high speed wind called hurricane with speed 140 Km/hr -400 Km/hr; thunder & lightning; Heavy rainfall due to cumulo-nimbus clouds;Cloud Bursts; Zone of convection.
 3.Inner Ring:
  • Dia:50-60 Km;wind speed around 60-80 Km/hr;rainfall due to cumulus cloud;
 4.Outer Ring:
  • wind speed around 40 Km/hr; Gentle breeze; Pleasant whether; some drizzles by strato-cumulus cloud;
 5.Annular Zone

  • Radius from center is 500-600 Km; surrounds whole cyclone; zone of subsidence and high pressure

Comments

Popular posts from this blog

DAVIES,PENCK & KING

Geographical Cycle of Davies William Morris Davies was an american geographer who gave first general theory on landform development.. Davis' most influential scientific contribution was the "geographical cycle",  which he defined in an article,’ The Rivers and Valleys of Pennsylvania ,’ published at the end of 19th century. According to him, uplifted landmass undergoes sequential development or erosion till base level in various stages.This sequential development referred as cycle of erosion. FUNDAMENTAL PRINCIPLES 1.Cyclic nature of landform evolution. 2 Uniformitarianism:The same physical processes and laws that operate today, operated throughout geologic time, although not necessarily always with the same intensity as now BASIC POSTULATES Upliftment takes place on featureless plain which he modified 10 yrs later to accept it can occur from geosyncline. Upliftment on geological timescale is sudden.In later works, he accepted it to be episodic. ...

Rene Descartes: A Critique

Introduction René Descartes (1596-1650) was a French philosopher, mathematician, and scientist who is considered one of the founders of modern Western philosophy. He is known for his contributions to analytic geometry, his development of the scientific method, and his famous philosophical statement "Cogito, ergo sum" ("I think, therefore I am"). Descartes is also known for his works on metaphysics, epistemology, and the philosophy of mind. Descartes' ideas had a significant impact on the development of Western philosophy and science. His emphasis on reason and mathematical reasoning as a tool for discovering truth has been influential in the development of the scientific method. Additionally, his ideas on the separation of mind and body and the nature of reality have continued to be influential in modern philosophy. Descartes' works include "Meditations on First Philosophy," "Discourse on the Method," and "Principles of P...

Diving into the Depths of the Unconscious: A Comprehensive Exploration of Carl Jung's Red Book

Carl Gustav Jung's Red Book: Liber Novus is not just a book; it's an experience.  A sprawling, intensely personal, and visually stunning journey into the depths of Jung's psyche, it documents his confrontation with the unconscious and his exploration of the symbolic language of dreams and visions.  Far from a dry academic treatise, it's a vibrant tapestry of text and image, a testament to the power of the unconscious and its profound influence on the individual and collective human experience.  This exploration delves into the Red Book's genesis, its core themes, its unique format, and its lasting impact on our understanding of the self. The Genesis of the Red Book: A Descent into the Unconscious The Red Book's story begins in 1913, a period of intense personal and professional upheaval for Jung.  His break with Sigmund Freud, the founder of psychoanalysis, had left him feeling isolated and disoriented.  Haunted by vivid dreams and visions, Jung embarked on a jo...