Astro Meteorology II , About Edava Pathi & Thula Varsha
After three days of dark clouds, lightning and rainfall, Kerala is back to normal.
Rains are expected to accelerate after Edava Pathi, which starts on May 29, when the Sun transits the 15th degree of Sidereal Taurus.
Jupiter in watery Pisces, Mars in Leo and Venus in Gemini should bring rains to Kerala.
Monsoons have been defined as sea breezes or wind systems. A wind system which reverses direction seasonally, blowing from the southwest for six months and from northeast for six months. Its extreme examples are in South Asia and Africa. Winds which influence climatic seasons, with concomitant rainfalls !
Annual temperature trends over sea and land are the causes of the monsoons. Monsoons normally blow from cold regions towards warmer regions. They blow from the sea towards land during summer and from land towards sea during winter.
Of all monsoons, the Edava Pathi or Kala Varsha is the largest. This Asian monsoon is the atmospheric response to the shift of the overhead Sun, from the Tropic of Capricorn in Dec to the Tropic of Cancer in June.
India lies exactly on the Tropic of Cancer, the apparent position of the Sun at the summer solstice. It is 23 degrees and 27 minutes ( which is the maximum declination of the Sun ) north of the Equator. India also lies on the equator. Pakistan lies north and is more drier than India. Pak does not get these monsoons.
Edava Pathi or Kala Varsha
In June, when the Sun comes at the Tropic of Cancer, the Northern part of India gets heated up, particularly the Thai desert. Physics has it that the land heats up faster than the sea, propelling the hot air on land to rise. Cool winds come from the opposite direction, the Indian Ocean, to replace the hot winds. They pick up moisture and move fast, hitting the Southern tip of India, Southern Kerala. As the Sun enters the 15th degree of sidereal Taurus ( May 29 ), Kerala receives these rains. Heavy precipitation occurs and it hits Andmans on May 20, Bombay on Jun 10 and Delhi on June 15/20 !
The exact reverse happens when the Sun comes overhead at the Tropic of Capricorn point, heating up the Indian Ocean. The Northen part of India becomes cool. The hot air rises and cool air from the Bey of Bengal pick up moisture and heavy precipitation occurs, accompanied by thunder and lightning. This is the Thula Varsha, which normally come in the evening, after 3, with fireworks, lightning and thunder. Tamil Nadu receives these rains and Kerala gets about 1000 m from Thula Varsha. This is the Retreating Monsoon, as there will be rains in Thula or sidereal Libra and less rains in Vrischika or sidereal Scorpio and the hot season begins from Dec to 17 to May 29 - 165 days of hot, torrid climate for all Indians !
The Malabar Coast of 825 kms, stretching from Bombay in the North to Cape Comorin in the South, gets maximum annual rainfall. The three types of rainfalls, Kala Varsha, Tula Varsha and Venal Varsha grace this costal belt of Maharashtra, Goa, Karnataka and Kerala.
The eastern parts of the Western Ghats do not get the Edava Pathi and hence places like Madras do not get its blessings. Madras gets the Thula Varsha in Oct-Nov, after Karkyadi ( when the Sun enters the first degree of Cancer ), when the Sun retreats South ( Dakshinayana ), when the northern side of the Indian subcontinent becomes cool and the cool winds from there precipitate the Thula Varsha.
Physiologists like Dr Walter Cannon ( The Wisdom of the Body ) talked about self regulating mechanisms or homeostatic control systems in the body physiologic.
Arent these monsoons the homeostatic or self regulating control systems of Divine Nature ?
One is reminded of a verse from Longfellow
Nothing that is shall perish utterly
But shall revive again
As clouds restore through rain
The exhalations of the land and the sea !
I follow two philosophers this way
It was Nature, Nature, all I heard them say !
By Govind Kumar