New Delhi: India's core monsoon zone covering most of the rain-fed agriculture areas in the country are predicted to receive above-normal rainfall this season, the India Meteorological Department (IMD) said on Thursday.
Below-normal monsoon rainfall is expected in northeast India, normal in northwest, and above-normal in central and south peninsular regions of the country, Director General of IMD Mrutyunjay Mohapatra said at a virtual press conference.
Last month, the IMD said the country could see above-normal rainfall in the four-month monsoon season (June to September) with cumulative rainfall estimated at 106 per cent of the long-period average of 87 cm.
"India's monsoon core zone comprising most of the rain-fed agriculture areas are likely to receive above-normal rainfall (more than 106 per cent of the long period average)," Mohapatra said.
Madhya Pradesh, Rajasthan, Maharashtra, Odisha, Chhattisgarh, Madhya Pradesh, Uttar Pradesh and West Bengal form the country's core monsoon zone where agriculture is primarily rain-fed.
The IMD director general said the country is likely to experience normal rainfall (92-108 per cent of the long period average of 166.9 mm) in June.
"Barring a few parts of southern peninsular India, normal to above-normal maximum temperatures are expected in the country in June," the senior meteorologist said, adding that conditions are favourable for monsoon onset over Kerala in the next five days.
With the crippling heat testing power grids and triggering drought-like conditions in parts of the country, a prediction of above-normal monsoonal rainfall comes as a huge relief for the nation.
However, normal cumulative rainfall does not guarantee uniform temporal and spatial distribution of rain across the country, with climate change further increasing the variability of the rain-bearing system.
Climate scientists say the number of rainy days is declining while heavy rain events (more rain over a short period) are increasing, leading to frequent droughts and floods.
The monsoon is critical for India's agricultural landscape, with 52 per cent of the net cultivated area relying on it. It is also crucial for replenishing reservoirs critical for drinking water, apart from power generation across the country.
According to the Central Water Commission, water storage in 150 major reservoirs in India dropped to just 24 per cent of their live storage last week, exacerbating water shortages in many states and significantly affecting hydropower generation.
June and July are considered the most important monsoon months for agriculture because most of the sowing for the Kharif crop takes place during this period.
El Nino conditions are prevailing at present, and La Nina may set in by August-September, scientists say.
While El Nino -- periodic warming of surface waters in the central Pacific Ocean -- is associated with weaker monsoon winds and drier conditions in India, La Nina -- the antithesis of El Nino -- leads to plentiful rainfall during the monsoon.
Data from the 1951-2023 period shows India experienced above-normal rainfall in the monsoon season on all nine occasions when La Nina followed an El Nino event. The country gauged above-normal or normal monsoon in 20 out of the 22 La Nina years.
The IMD is also anticipating the development of a positive Indian Ocean Dipole (IOD) or cooler-than-normal Indian Ocean in the east compared to the west, which helps bring rain to several states in southern India. The IOD is currently 'neutral' and is expected to turn positive by August.
Another factor is below-normal snow cover in the northern hemisphere and Eurasia. Historically, there has been an "inverse relationship" between the levels of snow here and the monsoon.