Shift in monsoon pattern feared: IMD

Shift in monsoon pattern feared: IMD

New Delhi: The dramatic recovery in the monsoon in the last seven days notwithstanding, the head of the India Meteorological Department (IMD) has warned against a structural shift in the pattern of the annual rainfall that could yet force a change in cropping patterns in the country.

While IMD maintained the situation was still being reviewed, it said that some of the adverse climate conditions of last year, which eventually resulted in a drought, seem to be playing out in the current year too.

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Typically, rain-bearing depressions, a precursor to cyclones in the Bay of Bengal and originating along the east coast of India, bring rains to key rice, oilseed and wheat-growing regions such as eastern Uttar Pradesh, Jharkhand, Madhya Pradesh and Orissa. The “abnormal conditions" are now threatening the dependability of the monsoon.

“There have been no depressions and few low pressure systems (a prelude to a depression) over the Bay of Bengal," said Ajit Tyagi, IMD director general. “If such a situation persists for few more years, then the whole monsoon itself will be affected. Why all of this is happening is still an open research question, and we, too, are trying to understand this."

Other experts said that barring El Nino (a heating of waters in the central Pacific region associated with droughts over India), monsoon conditions this year were similar to last year, which saw India’s worst drought in 37 years and indirectly worsened food price inflation. El Nino did not recur this year.

Until last week, the all-India monsoon deficit was nearly 14%, with most of the shortfall due to limited rains in central and east India. As of Friday, the monsoon deficit improved to 5%, which Madhavan Rajeevan, a senior meteorologist with the Indian Space Research Organisation called a “lucky phenomenon", rather than a genuine monsoon revival.

Rajeevan said that the key to good rainfall over central and east India were a good number of low-pressure systems. “Normally, July-end should’ve seen at least seven-eight low pressure systems. This year there were no more than three. That’s been a trend that we’ve been seeing for a decade, and that’s worrying," he said.

Low-pressure systems brought moderate drizzles over wide swathes—beneficial for agriculture—and depressions typically lead to concentrated bursts of rainfall.

This year IMD, in its first forecast for the June-September monsoon, had said rainfall would be 102% of the 50-year normal, buoyed by heavy rains in August and September.

The monsoon generates nearly 80% of the annual rainfall over the country and is vital for the economy, being the main source of water for agriculture, which generates about 17% of India’s gross domestic product. Other than the 60% of the country’s workforce that depends on agriculture, the rains are also important for traders dealing in food and cash crops as any shortfall can inject volatility in the markets.

The beneficial rains so far this year have largely been due to a phenomenon known as western disturbances that usually lead to pre-monsoon rain, and unusually active pressure systems in the Arabian Sea.

An IMD scientist, who didn’t want to be identified, said that changes in cropping patterns would have to be effected to offset shifting monsoon patterns. “There are changes in the monsoon patterns. If Indian farmers refuse to adapt, then there could be a problem. Western disturbances can’t pull the extra weight every year," he added.

However, IMD, in a mid-term appraisal of the monsoon on Friday, said that rainfall in August and September would be a staggering 107% of the 50-year average. “That’s more statistics than reality," said Rajeevan. While he too didn’t rule out a normal monsoon, he added that certain parts of India would receive far more rainfall than others.

“Every year, even normal monsoon rainfall (patterns) are different. Most times when one system weakens, another strengthens," Rajeevan said. “Trouble is, it’s become harder to say which, and when."