The South-West monsoon during June-September 2013 was 6 per cent above the long period average (LPA) of 89 cm (average of 1951-2000) as against 8 per cent below LPA last year. This was 8 per cent higher than the India Meteorological Department (IMD) forecast of 98 per cent LPA for the season, and the highest margin by which the season’s precipitation has exceeded the LPA in the last nineteen years. Additionally, the monsoon has been accompanied by other favourable factors, namely, on time arrival, well distribution – spatially and temporally, so much so, that 86 per cent of the geographical areas received normal rainfall during June-September covering 30 meteorological sub-divisions out of the total 36, which in turn replenished the major reservoirs of the country to levels higher than the previous year and the normal. These favourable factors have immensely benefited kharif sowing for 2013 which has surpassed the area sown last year and its normal level, the result being higher estimated production of most kharif crops including foodgrains, pulses and oilseeds by 0.9 per cent, 1.7 per cent and 14.8 per cent, respectively, during 2013-14 as per the first advance estimates which are expected to be revised upward as the season progresses. As regards rabi crops, with the reservoir levels continuing to be above normal and the previous year and the North-East monsoon so far turning out to be much above LPA, the prospect of a good harvest has improved. On the whole, the confluence of these favourable factors are expected to significantly boost agricultural growth prospects during 2013-14 to level higher than the previous year.

Introduction

The pattern of rainfall in India can be broadly classified into four seasons viz., South-West monsoon or the summer rainfall during June-September, the post monsoon rainfall or the North-East monsoon during October-December, winter rainfall during January-February and pre-monsoon rainfall during March-May. In general, the summer monsoon accounts for around 75-80 per cent of rainfall in the country, post monsoon around 10 per cent, winter rainfall 3 per cent and pre-monsoon 11 per cent.

The months of July-August, when the South-West monsoon, the main source of rainfall in the country is at its peak is also a crucial period for kharif sowing. Therefore, the on time arrival and even distribution – temporally and spatially, of summer rainfall is essential for a good kharif harvest. In the past, it has been observed that whenever the South-West monsoon is deficient kharif crops have failed (Chart 1). Since kharif season is the main cropping season, its failure often goes uncompensated, the net result being slowdown in the overall growth of agricultural sector. It is in this backdrop that this article provides a detailed review of the performance of South-West monsoon during June-September 2013.

South-West Monsoon 2013: Highlights

• South-West monsoon current advanced over the Andaman Sea 3 days earlier than its normal date of 20th May and set in over Kerala on its normal date of 1st June. The South-West monsoon covered the entire country by 16th June, about 1 month earlier than its normal date of 15th July.

• For the country as a whole, the rainfall for the season (June-September) was 106 per cent of its LPA.

• Seasonal rainfall was 109 per cent of its LPA over North-West India, 123 per cent of its LPA over Central India, 115 per cent of its LPA over South Peninsula and 72 per cent of its LPA over North- East India.

• Out of the total 36 meteorological sub-divisions, 14 sub-divisions constituting 48 per cent of the total area of the country received excess rainfall, 16 sub-divisions (38 per cent of the total area of the country) received normal rainfall and the remaining 6 sub-divisions (14 per cent of the total area of the country) received deficient rainfall.

• Monthly rainfall over the country as a whole was 132 per cent of its LPA in June, 106 per cent of LPA in July, 98 per cent of LPA in August and 86 per cent of LPA in September.

• Out of the total 641 districts, 100 were affected by moderate meteorological drought (seasonal rainfall deficiency of 26 per cent to 50 per cent), while 39 were affected by severe meteorological drought (seasonal rainfall deficiency of 51 per cent to 99 per cent)

• The withdrawal of monsoon from west Rajasthan commenced on 9th September compared to its normal date of 1st September. After 19th, further withdrawal of South-West monsoon was stalled with the successive formation of two low pressure areas and their westward movement across the central parts of the country.

Forecast: South-West Monsoon 2013

The IMD forecasted a normal South-West monsoon at 98 per cent of LPA in its first stage long range forecast for the season (June-September) issued on April 26, 2013 and the subsequent update issued on June 14, 2013 with margins of errors placed at ±5 per cent and ±4 per cent of LPA, respectively. However, the actual rainfall at 106 per cent of LPA for the season turned out to be even higher than the June update of 102 per cent. The actual rainfall for the second half of the season (August–September) at 94 per cent of LPA was within the forecast limit of 96 per cent with the margin of error of ±8 per cent LPA. The actual rainfall for the months of July, August and September were also within the forecast limits (Table 1).

Distribution of Rainfall: South-West Monsoon 2013

As regards the four broad geographical regions of India, the South-West monsoon rainfall was expected to be 94 per cent of its LPA over North-West India, 98 per cent of LPA over Central India and North-East India and 103 per cent of LPA over South Peninsula with a model error of ± 8 per cent. The actual rainfall over North-West India, Central India and South Peninsula was, however, 9 per cent, 23 per cent and 15 per cent above their respective LPAs. Rainfall over the North-East India fell short by 28 per cent of LPA (Table 2).

Spatial Distribution

The cumulative rainfall during June-September 2013 was excess/normal in 30 out of the 36 meteorological sub-divisions accounting for 86 per cent of the geographical area of the country. The corresponding positions for the previous year were 23 sub-divisions and 67 per cent, respectively (Chart 2, Table 3 & Statement I).

Temporal Distribution

The monthly rainfall during the last two months (August and September) of the monsoon season was less than their respective LPA values. June and July, however, received above normal rainfall. During most part of the season, 3 sub-divisions in North-East received deficient rainfall. On the other hand, most of the sub-divisions in Central India and neighbouring North-West India and South Peninsula received excess rainfall during the first 3 months of the season. No sub-division experienced scanty rainfall during the first 3 months of the season though 4 sub-divisions received scanty rainfall during September (Table 4).

Production Weighted Rainfall Index

The foodgrains production weighted rainfall index (PRN) is constructed by the Reserve Bank, based on the weighted average of actual rainfall received by the States where weights are taken as the average share of foodgrains production of a particular State in the overall foodgrains production¹. As per this index, the rainfall during South-West monsoon 2013 was 2 per cent above normal as against 13 per cent below normal the previous year (Chart 3).

Reservoir Status

In India, the Central Water Commission monitors the total live water storage in 85 major reservoirs with a full reservoir level (FRL) of 154.87 billion cubic meters (BCM). As on October 3, 2013 the level of water (total storage to live capacity) in these reservoirs was 86 per cent as against 74 per cent during the corresponding period last year and the average of last ten years at 73 per cent (Table 5).

Progress of Sowing and Kharif Production Estimates

A normal and evenly distributed South-West monsoon, devoid of extreme climatic events facilitated the coverage of area sown to levels higher than the season’s normal and the coverage last year. The higher area coverage along with a low base effect is reflected in an improvement in kharif crop 2013. The First Advance Estimates 2013-14 of production of foodgrains have placed Kharif foodgrains at 129.3 million tonnes, up by 0.9 per cent over the previous year’s Fourth Advance Estimates (Table 6). The final figure of kharif production in 2013-14 is expected to be higher as estimates get revised upward with the progress of cropping season and availability of more information from the States.

Conclusion

The South-West monsoon during June-September 2013 was 6 per cent above LPA, the highest in 19 years, as against 8 per cent below LPA in the previous year. The timely arrival and uninterrupted distribution of rainfall, temporally and spatially, barring parts of East and North-East region, through June-August contributed to the attainment of higher area coverage during the current kharif sowing season. Consequently, the First Advance Estimates for most kharif crops in 2013-14 have shown an improvement over last year. With the reservoir position being comfortable, and the North-East monsoon also turning out to be much better than the previous year, the prospect of rabi crops have also improved. On the whole, based on these favourable factors, agricultural growth during 2013-14 is expected to record a significant improvement over the previous year.

* Prepared in the Development Studies Division, Department of Economic and Policy Research, Reserve Bank of India.

¹ A Production Weighted Rainfall Index of 100 indicates normal rainfall, where normal represents average of last 10 years’ production weighted rainfall.