The pattern of southwest monsoon in recent years has necessitated a shift in cropping strategies by taking into account the change in the progress of the annual phenomenon across the country, according to experts.
The monsoon this year was marked for various changes from the conventional trend. The rains hit the Kerala coast earlier than usual and then came in a lull in its progress towards the rest of the country. This resulted in deficient June rainfall and then surplus downpour during July-September period. Also, the spatial distribution of rains was uneven and particularly patchy in the eastern region.
Stating that this year’s was not a ‘classical’ advancement of monsoon, Mrutyunjay Mohapatra, director general, India Meteorological Department (IMD) said that the surplus rainfall in September, considered as flowering stage of most of the kharif crops such as paddy, pulses, oilseeds, sugarcane and cotton, has impacted some of the standing crops. He called for change in the cropping pattern, in tune with the monsoon’s advancement.
An agriculture ministry official said that rainfall received during the last week of September, especially in the northern regions, has delayed harvest of paddy while it has helped in adding some areas under paddy in southern states.
The cumulative monsoon rainfall received in all the four regions during June 1-September 30 was 925 mm, 6.5% more than the normal bench mark (long period average) of 868 mm. According to private weather forecaster Skymet, this year’s above normal rainfall was ‘fourth successive good monsoon for the country,’.
“This monsoon season was very unique with contrasting month to month variation,” IMD has stated in its preliminary report on monsoon, 2022. The rainfall over the country as a whole was (-) 8%, 17%, 4% and 8% of the LPA during June, July, August and September respectively.
Mohapatra said that while the met department could not accurately predict the extent of deficient rainfall in key rice growing states of Uttar Pradesh, Bihar, Jharkhand and West Bengal. Resurgence of rainfall in these states in August and September reduced deficiency from 47-48% in June-July to around 25-30% by end of September.
The rainfall deficiency in the east and north-east has been 18% against the benchmark while central India, the south peninsula, north-west regions have received 19%, 22% and 1% more rainfall than the LPA.
During this kharif season the paddy sowing area was 4.7% less on year owing to deficient rainfall received in eastern states, which is expected to pull down the country’s rice production by around 6% to 104.99 million tonne (mt) in 2022-23 crop season (July-June) against 111.76 mt in 2021-22. Area under paddy in West Bengal, the largest rice-producing state, was down by 8.6% on year.
Another characteristic of monsoon rains, according to IMD, has been that the number of light and moderate rainfall days have been decreasing, while the number of days with heavy rainfall intensity have increased.
Stating it’s a challenge to predict severe weather events such as heavy rainfall, heat wave and thunder storm, at local levels for helping farmers, Mohapatra said that the met department has to improve weather forecasting accuracy at block or panchayat level while district level forecast has been fairly robust.
Keeping into consideration the changing pattern of monsoon rains, since 2020, IMD has shifted the monsoon withdrawal date from the northwest region from September 1 to September 17. It implies that complete withdrawal of monsoon takes place only by October 15 not by September 30.
Monsoon rainfall deviation of less than (-) 10% of LPA is considered ‘deficient; (-) 10 – 5% of LPA is considered ‘below normal’; (-) 4% to 4% is ‘normal’; 4 to 10% is considered ‘above normal and over 10% of LPA is considered ‘excess’.