Swinging in the rain: India needs to redefine what a “normal” monsoon looks like

From extreme precipitation to severe deficits—a look at the district-wise distribution of rainfall through June to September offers a glimpse of how distorted the picture of “normalcy” really is

The monsoon officially retreated from the Indian subcontinent last week. The outro saw torrential rains sweep Kerala and the Malabar coast as the Southwestern Monsoon withdrew from India after 130 days. Over this time, it wouldn’t be an exaggeration to say that the season was all over the place, punctuated heavily by extremes right up to the tail end of the season. 

The monsoon delivered 94% of the rainfall considered to be the Long Period Average (LPA) during the conventional monsoon season that spans June to September. The IMD’s end of season report declares the monsoon “normal”, with the core monsoon zone, featuring most rainfed agriculture regions of the country, registering 101% of the LPA rainfall. At the end of the four months, 73% of the country’s area was deemed to have received normal rains, 18% saw deficient rains and 9% of the country registered excess rainfall.

The overall normalcy projected by the IMD’s assessment of the season, however, rings dissonant with the stream of headlines that swung through the season between apocalyptic rainfall and crippling deficits. 

Devil is in the details

Cracks start appearing on the façade of normalcy as soon as one starts looking at how rainfall was distributed throughout the season. A sluggish start in June was followed by a tempestuous July. An el Nino building up in the Pacific brought the monsoon to a standstill with rainfall in the critical month of August plunging to 36% below average. Drought was ultimately averted as rains returned in September owing to favourable conditions in the Indian Ocean in September. 

An analysis of the daily district rainfall sheets from June up to the last week of September suggests barely any sense of normalcy in the distribution of rainfall. About 6% of the 81,852 district rain days during the four months of monsoon analysed by CarbonCopy and Climate Trends registered normal rainfall. By comparison, over 60% of the district-wise daily rainfall data showed large deficits (deficits of over 60%) or no rain. It is understood that normal rainfall data has been averaged out over several years and cannot be expected to indicate the consistency of rainfall, but the relatively miniscule number of “normal” rainfall days experienced by India’s 718 districts does reflect a reality of being swung between extremes. August was unsurprisingly the worst performing month, with over 76% of the district rain days registering large deficits or no rain. The week-by-week rainfall performance assessment of India’s 36 meteorological sub-stations over the 17 weeks of the monsoon reveals that almost half of all weekly observations show rainfall deficits of at least 20%. 

Swinging between extremes

If almost two-thirds of the district rainfall days either registered large deficits or no rain, it begs the question of how seasonal normalcy has come about. The answer of course lies in the spells of excessive rainfall, particularly in July, and a generous peppering of very heavy and extreme rain events. Despite ending the season with just 94% of the LPA rainfall, the country saw the second-highest number of heavy rain events (over 115.6mm rainfall received) in the past five years. In 2019, when the country saw 3,056 heavy rain events, about 10% higher than this year’s 2,742 events, seasonal rainfall recorded was 110% of the LPA. While almost half of all heavy rain events this year came in the month of July, June saw the highest number by far in the past five years despite registering a substantial shortfall in rainfall over the country.

Interestingly, these excesses came overwhelmingly from Western and Central India, conventionally considered among the drier parts of the country—specifically the West Rajasthan, Saurashtra-Kutch and Western Madhya Pradesh meteorological subdivisions. These regions are also prominently dotted in the mapped distribution of heavy rain events. 

Wet plot

This year saw unusual concentration of extreme rain in conventionally dry pockets of country and the lower Himalayan region | Source: IMD 2023 Southwest Monsoon End of Season Report 

On the other hand, regions like Kerala, Gangetic West Bengal, Bihar, Jharkhand, and northeastern states, which are usually top contributors during the season, remained dry due to deficient rainfall. During the four-month span, Kerala was not able to cover the rainfall deficiency. As a result, the state ended with a high rainfall deficiency of 36%, wherein out of 15 districts, 11 were in a rain deficit, and only four stations managed to see normal rains, albeit on the negative side.

In Bihar, 21 districts out of 38 districts reported deficit rainfall, while 17 had managed to be in the ‘normal’ category, but on the negative side. Meanwhile, heterogeneous regions of East and Northeast India underperformed this Monsoon, accruing an overall deficiency of 18% rainfall. The region has recorded negative rainfall nine out of the past 10 years. This can also be seen as a deviation from the norm, which suggests better performance in the region when El Nino suppresses rainfall over the rest of the country.

The strong build up of temperatures in the Pacific was enough to instigate a prolonged collapse of monsoon distribution. Closer to home, however, anomalous heating observed in the Arabian Sea effectively contributed to the shifting of the monsoon trough away from the Western coast and Northeast India and towards Northwestern and Central India—a clear indication of the imprints of global warming, which are also firmly in line with projections of a wetter future for Central India under a warming planet. The distribution of this year’s monsoon, a clear deviation from the established convention, is a stark reflection of how warming is compounding already complex interconnections that regulate monsoon winds.

The growing impact of extreme rainfall events

The challenge posed to conventional tropical meteorology by climate change is substantial in itself. The true extent of what it entails, however, is apparent in the multitude of systemic inadequacies in coping with this challenge.

With every passing year, the growing impact of extreme rain events in India becomes more and more apparent. This year was no exception. Two weeks ago, the South Lhonak glacial lake in the upper reaches of Sikkim, burst its banks following a cloudburst in the area. Bodies are still being discovered as the death toll hit 40, with more than 70 still missing. Devastating rains in Himachal Pradesh and Uttarakhand, overflowing Yamuna and submerged Capital, “flood-like situation” in multiple districts of arid Rajasthan, submerged Ujjain temples and ghats in Madhya Pradesh, and so on. 

To talk about economic loss due to flooding in the country, it is estimated to be around $3 million per year for the past few decades. Also, in the previous 50 years, about $60 billion loss was solely due to regional floods, out of $99 billion lost from extreme weather events such as floods, tropical cyclones, heat waves, cold waves, lightning, etc.

After the heavy rains, floods, and landslides wrecked Himachal Pradesh, the state assembly has passed a resolution demanding ₹12,000 crore from the Centre for reconstruction work. Record-shattering rainfall in northern parts of the country not only shed light on the increasing intensifying weather extremes, but also on lack of preparedness to deal with them and the ineffectuality of redressal mechanisms.

“Traditionally, people were not building houses on riverbeds, but only on the ridges where foundation is more stable. If you construct everywhere and cut trees, then the kinetic energy of the rain is strong enough to destabilise the topsoil. The areas that were absorbing water have decreased because of the construction activities and, therefore, the runoff has increased a lot,” explained Manoj Pande, program director, SIUD & I/C Urban Development Cell,CGG Dr RS Tolia Uttarakhand Academy of Administration, Nainital. 

According to Pandey, apart from evaluating the carrying capacity of these regions, it is vital how water is drained from these hilly areas. Seeped in water and underground water channels might also disturb the underground structure, which probably has happened in Joshimath, Pandey added. According to a post-disaster needs assessment carried out by government authorities, the absence of a building permission system surfaced as one of the main causes of the substantial damage to homes in the subsidence-hit area of Joshimath in Uttarakhand. The report is also urging the government to declare Joshimath as a “no construction zone.”

“For any hilly area, it is important to draw out the water, which falls on the surface through storm water drains. But because of the rampant construction, the previously designed stormwater drains have to be looked into and revisited,” added Pandey. 

Ill-planned development models compromise the existing basics of disaster management. Stormwater drains in Himachal and even in New Delhi are poorly maintained, covered to increase space for traffic and are being used to carry sewage and waste instead. Parts of the Capital were submerged for days as Yamuna crossed its danger mark and flood-like situation prevailed in the city. A couple of months ago, the National Green Tribunal (NGT) ordered the formation of a joint panel to look into the matter of sewage being released into stormwater drains in the city. The Bombay High Court has also ordered using best possible technology to rehabilitate 100 years old storm water arch drains in Mumbai as the city struggles every monsoon.

However, for Rajasthan, a conventionally dry state, sudden extreme rain events can catch those regions off guard where such rain is not a norm. For example, extreme rains in Rajasthan earlier in June this year as cyclone Biparjoy moved across the state after making a landfall in Gujarat led to water-logging, resulting in five deaths and requiring rescue operations by the army. 

The following month in July, in many places of eastern and central Rajasthan, heavy monsoon rains put a stop to daily activity by flooding highways, rail tracks, low-lying residential areas, and even hospitals. About a week ago, it was Rajasthan’s neighbouring state Madhya Pradesh that witnessed extreme rain in several parts. 

Extreme rainfall events in central India ie in states like Madhya Pradesh are increasing. A 2017 study found that extreme rain events over central India have tripled over 65 years, with an ongoing upward trend. “In MP, among the many practices, embankments or retaining walls made to protect the house against the natural terrain, often result in disaster for the city. Also, there is a lack of standardised regulations for plinth level and percentage of open green space inside the plot. The heavy precipitation water needs to flow naturally into permeable surfaces or drain out of the city naturally using natural slopes. The city planning needs to be respectful of the physical features, terrain , soil etc, defining climate sensitive urban morphology that allows natural water flows. It is high time that Madhya Pradesh planning regulations addressed this issue, considering its unique character,” said Dr Surabhi Mehrotra, assistant professor, Maulana Azad National Institute of Technology(NIT), Bhopal. 

Among the mortality from all other extreme weather events, floods alone contribute 46.1% of the mortality in India. 

Impact on agricultural practices

In a country where rain-fed agriculture employs approximately 67% of the net sown area, supplying 44% of the food grains, extreme rain events are not only threatening sowing practices across the country, but also food security.

On July 10, IMD and the Indian Council of Agricultural Research (ICAR) issued a National Agromet Advisory Services Bulletin warning multiple states to postpone planting kharif crops. Forecasting above normal rains in Rajasthan, Punjab, Uttar Pradesh, among other states farmers were advised to postpone irrigation in summer crops and all types of chemical spraying in the fields. They were also advised to drain out excess water from the groundnut and green gram crop fields in Rajasthan. In Punjab, removing excess water from maize fields was recommended, as standing water can have a detrimental impact on maize crops, leading to the development of stalk rot. While in Uttar Pradesh, farmers were told to drain excess rain water from the rice nursery and sow short duration rice varieties, along with postponing the sowing of kharif maize. 

It should be noted that India banned export of non-basmati white rice on July 20, citing concerns regarding domestic supply. Talking of restrictions, the government on August 19 imposed a 40% duty on the export of onions until the end of the year to infuse stocks into the market to stabilise prices and mitigate the demand-supply mismatch. The reasons for this could be traced back to February, when higher-than-normal temperatures were observed, followed by unseasonal rainfall between late March and early-April. This affected the growth cycle of the onion crop. 

On the other hand, the lack of usual rainfall and a patchy monsoon led to the government extending free import of two pulses, tur and urad, till March 2024. Domestically, the Centre imposed stock limits on these two pulses to control prices earlier in June due to the foreseeable El Nino weather pattern. India also banned wheat export last year after a record-breaking heatwave resulting in reduced production of wheat domestically. Recently, the country has also extended the restriction on the export of all varieties of sugar beyond October 31. This is because the top regions that together account for more than half of India’s total sugar output in Karnataka and Maharashtra received about 50% below average rainfall this year.

Data from 70% of the country indicates drought, but governments won’t declare 

According to the Centre’s Manual for Drought Management, October is the best time to declare drought as the monsoon is over by this month and figures for total rainfall are available in this month. Similarly, a final picture regarding the crop conditions as well as the reservoir storage is available by the end of October. It provides adequate time for the central team to visit the State and assess the crop losses.  

Despite an active monsoon in September, Standardised Precipitation Index (SPI) data released by India Meteorological Department (IMD) for the period from June 1, 2023 to October 4, 2023 shows meteorological drought conditions, ranging from mildly dry to extremely dry, prevailing in 460 of India’s 718 districts covering nearly 60% of the country. Experts say high temperatures as well as poor spatial distribution of rains coupled with prolonged breaks in August may be responsible for the ubiquitous drought conditions.  

The plight of farmers in Odisha exemplifies how the wonky distribution was absorbed on the ground. Because of rain deficits in July and August, paddy crops failed and farmers of Odisha’s Nuapada district were forced to migrate to Andhra Pradesh, Telangana, Tamil Nadu and Karnataka for work six months earlier than their usual migration in December to pay back their debts. In July, Nuapada received 14% deficit rains, while Khariar and Sinapali blocks saw a prolonged dry spell of 25 days as they registered a deficit of 35%.

The Karnataka government weeks ago declared 195 taluks in the state as drought-hit, owing to weak monsoon. Among them, it announced that 161 taluks have been declared as severely drought-hit and 34 taluks as moderately drought-hit. 

District-wise drought forecast and categorisation 

The countrywide forecast map released by IIT Gandhinagar’s India Drought Monitor in September categorised districts under extreme stages of drought. 

Drought country

The drought map is based on data of Standardised Precipitation Index, Standardised Runoff Index and Standardised Soil Mixture index. Kerala recorded 48% rainfall deficit, with Idukki district at 62% deficit. Deficit in violence-hit Manipur is at 46%, with two districts at 81-84% deficit and some districts in Uttar Pradesh are running at 60-70% deficit, pointed out climate scientist Roxy Koll. The deficits in monsoon are clearly evident in the concerning levels of water storage reported from Southern India and UP, where current water levels in reservoirs are respectively 33% and 29% below their corresponding 10-year averages.

Drought relief fund: New norms make govt funds impossible to access? 

Analysts say prior to 2016, today’s rain deficit would have been considered a country-wide drought. Before 2016, the government followed the 2009 Manual of Drought Management, which allowed declaration of drought based on crop sown area (if the area sown was under 50% ). In 2016, the Centre revised the manual that made the process to declare a drought in a state cumbersome. 

If an unirrigated crop fails due to rain deficiency, consider the Ground Truthing (GT)/verification a farmer must pass to get the Centre/state to declare drought and release compensation. According to the manual, the GT needs to be conducted in each of the 10% of the drought affected villages, selected on a random basis. In each of these villages, about five sites for each of the major crops may be inspected using a smartphone based App. The GPS of the site and the photo of the crop is collected as data for post-facto analysis.

The manual further clarifies that the intensity of the drought will be contingent upon the values of at least three out of four Impact Indicators. First is meteorological data, which includes indices such as rainfall deficit. Secondly, hydrological data, which includes water level in reservoirs / ponds/ river flow, groundwater level, evaporation. The third indicator is agriculture, which includes soil moisture, area under sowing and type of crop, crop yield. Lastly, remote sensing, which includes vegetation monitoring, rainfall, surface wetness and temperature monitoring. 

Under the changed manual, the Centre contributes to the state relief fund only if drought is categorised as ‘severe’ and meets at least three impact indicators. Drought of ‘moderate’ category is allowed financial assistance from state funds. A crop loss of 33% or more will qualify for the declaration of drought. For the drought to qualify as ‘severe’, the crop loss should exceed 50%. 

The many avoidable levels of a deadly drought 

Deficient rain only triggers a meteorological drought, which is measured on the basis of dryness and precipitation shortage. If the shortage of rain is not handled through a robust policy of rainwater harvesting and groundwater banking, the situation turns into a hydrological drought, which is a result of below-average surface and subsurface flow for a longer time duration that accelerates inadequate water supply. When the sources of surface water dry up, the third stage of drought, which is categorised as agricultural drought, occurs due to low soil water availability to support agricultural growth. The fourth stage is  socio-economic drought, which leads to migration, loss of food and jobs, and hunger. 

Scientists recently have proposed another category of “ecological drought”, which is described as an extended and widespread shortage of water availability in ecosystems, leading to ecological stresses. In addition, a novel drought type called “flash drought” has been introduced into scientific research. Which is a subdivision of all droughts that is distinguished solely based on its rapid rate of intensification due to abnormal evapotranspiration. 

Agricultural drought to social-economic drought

The water shortage is a grave concern. Researchers say that with population, the annual demand for food will exceed 250 million tonnes and demand for grain will increase to 375 million tonnes (including grain for cattle) by 2050. The per capita consumption of cereals will decrease by 9%, 47% and 60%, (rice, coarse cereals, maize) and that of sugar, fruits and vegetables will increase by 32%, 65% and 78%, respectively, by 2050, requiring more water. Demand for water for livestock will rise from 2.3 billion cubic meters (BCM) in 2000 to 2.8 BCM in 2025 and 3.2 BCM in 2050, states a government report.

The India Meteorological Department (IMD) analysis says drought has become frequent and severe since 1965 and increased “remarkably” in northeast and central India predominantly impacting crop production. The loss of crops results in loss of food and income of a family and that of the country as well. The social and economic loss of drought is more severe than the physical loss by droughts in India, researchers say. 

Descending into madness

Like many monsoons from recent years, the 2023 season serves as a stark reminder that India’s hydro-climatology is not insulated from larger warming trends being observed around the world. Far from it, evidence suggests that it is highly sensitive to changes in local, regional and global climate indices. At this point in the climate change saga, ‘the new normal’ has become a cliche. Yet the clear challenges to convention—not just in tropical meteorology, but also in city and town planning, damage assessment and response to increasingly frequent extreme weather, have gone unanswered in any meaningful way. 

India’s inadequacies in dealing with an erratic monsoon (and erratic weather in general) will not vapourise by ignoring them. And still, the country continues seemingly unconcerned by the monumental questions it must confront in order to effectively tackle the dire implications of climate change. With climate change forcing ‘new normals’ on the conditions we operate under, it would seem that the only salvation from the prevailing lunacy is a systemic overhaul.

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Shreeshan V

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