There is wide variation in the quantity of rainfall received from place to place.
Highly erratic, undependable, variation in seasonal rainfall either in excess or
deficit are the nature of Indian rainfall. For example a place in Rajasthan receives
practically nil rainfall at the same time Chirapunji about 3000 mm rainfall.
Rainfall is not uniformly distributed throughout the year. It is seasonal, major
quantity is in the South West Monsoon, (SWM alone contributing 70% of total
rainfall) i.e. in the month of June to September followed by North East Monsoon
(NEM) from October to December. It summer and winter the amount of rainfall
is very little.
With in the season also the distribution is not uniform. A sudden heavy downpour
followed by dry spell for a long period is common occurrence.
Rainfall distribution over a large number of days is more effective than heavy
down pour in a short period, but it is in negative trend in India
Late starting of seasonal monsoon
Early withdrawal of monsoon and
Liability to failure are the freakish behaviour of Indian rainfall. Timely and
uniform distribution of rainfall is important for better crop planning and to sustain