What is the issue?
- The September of 2018 has seen a rainfall deficiency of 22.3% until the third week.
- It makes it the driest September in 17 years, with rainfall almost a third below normal.
How has rainfall been?
- According to IMD (India Meteorological Department) data, 12 of the country’s 36 meteorological subdivisions have registered deficient rainfall.
- This is a departure of nearly 20% from the Long Period Average (average annual rainfall for the period 1951-2000).
- It covers Gujarat, Bihar, Jharkhand, West Rajasthan, Haryana (including Delhi and Chandigarh), the entire North-East, Rayalaseema and North Interior Karnataka.
- South India has been dry this September, with a deficiency of over 46%.
- Not much rain is expected in the remainder of the month too leaving September with a deficiency of over 30%.
- Never since 2001, with a 35.8% shortfall, has September been so dry.
- The month is thus set to end up being the driest September since 2001.
- The shortfall has meant that there has been a 9% deficiency in the overall rainfall in June-September monsoon.
- Eastern and north-eastern India has a deficiency of almost 25% over the season.
What is the possible reason?
- According to the IMD, there were only six significant low pressure systems (LPS) this season.
- One or two LPS formed almost every day but most of these were not strong enough to bring in rain.
- So the lack of strong LPS developing over the Bay of Bengal side is likely the only cause of low rainfall.
- One of the reasons for this is that around the same time, some cyclonic activity in the west Pacific region was taking place.
- The moisture over the Bay of Bengal got sucked in by those systems.
- Evidently, Japan and Philippines had some good rainfall.
- Besides this there might not be any “external cause” behind the low rainfall in this month.
- In natural systems like monsoon, a drought can occur once in a few years without any external cause.
- So though the rainfall deviation is large, it doesn’t seem to be a result of any major atmospheric abnormality.
- Suggestions that a developing weak El Niño in the Pacific Ocean might have forced a suppression of rainfall are ruled out.
Will it affect agriculture?
- The poor rainfall activity is unlikely to significantly impact agricultural production.
- The main reason for this is that much of kharif plantings happen in June-July.
- Most parts, except Bihar, Jharkhand and the North-East states, received enough rains for farmers to take up sowing operations.
- Some areas such as Marathwada, North Karnataka and Gujarat (especially Saurashtra) did experience dry spells during the crop’s vegetative growth phase.
- But the situation is nowhere close to the drought situation seen in 2014 and 2015.
- There are concerns over the cotton crop in Gujarat’s main Saurashtra belt where moisture stress could affect yields.
- But fortunately, no large-scale pest attacks have been reported in the country’s major cotton-growing areas this time.
- Given all these, this year’s kharif crop would not be as good as in the last two years.
- But there is certainly no possibility of a repeat of the 2014 and 2015 drought situations.
- Moreover, further rainfalls, as predicted, would help bolster the soil and sub-soil moisture in the coming rabi sowing season.
- However, the Australian and U.S.'s meteorology departments have forecasted an El Nino event to take place after November.
- El Nino is the abnormal warming of the equatorial Pacific Ocean Waters, seen to adversely impact rains in India.
- This could possibly have a bearing on the winter rains, which are crucial for crops such as wheat, mustard and chana.
Source: Indian Express
