Deficit to deluge: India’s swinging monsoon test

How severe were the rains this time around?

From the morning of 8 July several northern states were lashed by heavy rains, breaching past records. While Delhi received 40% of its seasonal rainfall in just two days, parts of Haryana and Punjab went under water. In Himachal Pradesh, a downpour, combined with changing land-use due to infrastructure projects, led to the collapse of roads, bridges, and loss of property and lives. The extreme events pushed the monsoon into surplus zone. Till 30 June, the monsoon deficit for the entire country was 10% of the long period or 50-year-average. In just 10 days of deluge the numbers tipped over, recording a surplus of 2%.

What factors were responsible?

The India Meteorological Department (IMD) says the heavy rains were caused by a western disturbance interacting with the monsoon flow. The worst, it says, is over. As per the official forecaster, the rains had little to do with climate change. However, over the years, the heavy rain days have been rising while rainy days are declining—leading to a skewed distribution—due to climate change. Further, the IMD said that predicting the severity of an extreme rainfall is difficult. While it issued alerts for Himachal Pradesh, Haryana, and Chandigarh ahead of the deluge, for Delhi it had only forecast moderate rains.

Is global warming a factor behind this change?

Yes. Instead of rains spread across the four-month season, long dry spells are interspersed with heavy rainfall events. This is a clear climate change signal, explains Roxy Mathew Koll, a climate scientist. Warmer air holds more moisture and for a longer time. So, it does not rain for long periods. But when it does, all that moisture gets dumped in a short time.

What about the geographical spread?

Between 1 June and 11 July, 37% of India saw a rain deficit of 20% or more. In regions such as central Maharashtra, Marathwada, Karnataka, Kerala, Gangetic Bengal, Jharkhand and Bihar, the rainfall deficit is more than 30%. During this period, several parts witnessed excess rains including western UP (60% more than normal), Punjab and HP (more than double the normal), and parts of Rajasthan and Gujarat (more than three times the normal). The distribution of rains has been uneven across regions and time.

What does this mean for kharif crops?

Till 9 July, the area under kharif crops was 5% lower on-year, due to lower planting of rice, pulses and oilseeds. While the lag in planting area will likely shrink as the numbers are updated, the impact of truant rains will be felt by farmers. Whether hit by acute deficit or excess rains, farmers will be spending on replanting and associated costs as saplings wither or get washed out. These costs are rarely reflected in official data. For consumers, the recent deluge is likely to push cereal and vegetable prices higher.