Drought

Topic: Natural Hazards and Disaster Management in India · NCERT: Class 7, Ch 2 "Understanding the Weather"; Class 9, Ch 3 "Atmosphere and Climate"; Class 11, Ch 6 "Natural Hazards and Disasters: Causes, Consequences and Management"

Meaning

Drought is a long period when there is not enough water. It is caused by too little rain, high evaporation (heat turning surface water into vapour) and overuse of water stored in reservoirs and underground (groundwater). It matters because India's monsoon is unreliable. About 30% of India's area is drought-prone, so a single bad monsoon can cause crop failure, cattle deaths, migration and rising food prices.

Explanation

How a drought builds up

• Drought is a complex hazard. It has many linked parts:
• precipitation (rain and snow)
• evapotranspiration (water lost from soil by evaporation, plus water given off by plants)
• groundwater, soil moisture, water storage and runoff (rainwater that flows off the land into streams)

• cropping patterns, social and economic practices, and ecology

• It is a slow-onset hazard.

• A cyclone or an earthquake strikes suddenly.

• A drought builds up slowly over weeks and months.

• The same monsoon can cause opposite hazards:

• In one season, one region can have floods while another has drought.

• In different seasons, the same region can face both floods and drought.

• The chain of events:

• First the rain fails (meteorological drought).
• Then the soil dries and crops wilt (agricultural drought).
• Over months, rivers, tanks and wells run low (hydrological drought).
• Finally, forests, grasslands and wetlands suffer (ecological drought).

Types of drought

Type	What runs short	Test or trigger	Timing
Meteorological	Rain: too little for a long time, and badly spread over the season	IMD: seasonal rain more than 25% below normal. 26-50% below = moderate; more than 50% below = severe	Comes first
Agricultural	Soil moisture, so crops fail	An area with more than 30% of its gross cropped area irrigated is not counted as drought-prone	Follows a rain shortage in the crop season
Hydrological	Water in aquifers (underground layers of rock or sand that hold water), lakes and reservoirs falls below what rain can refill	Falling reservoir levels, groundwater levels and stream flow	Comes after meteorological drought
Ecological	Water for a natural ecosystem	Water stress stops the ecosystem from being productive and damages the environment	Can last after the rain returns

• Gross cropped area: all the area sown in a year. Land sown twice is counted twice.

How India declares a drought: Manual for Drought Management (2016, updated 2020)

• What changed: old estimates by revenue offices were replaced by a test based on data and satellites. States must follow the manual when they declare a drought [2].
• Step 1: Mandatory indicators [2]
• rainfall deviation (how far rain is from normal, in %) or SPI (Standardised Precipitation Index: a score of how unusual the rain is compared with past rain)

• plus a dry spell: usually 4 weeks with little or no rain (3 weeks on light soils; 2 weeks on sandy soils)

• Step 2: Impact indicators. The state picks any 3 of 4 [2]:

• the crop situation, such as sown area compared with normal
• remote-sensing vegetation indices: NDVI (how green the plants are), NDWI (water in plants) and VCI (Vegetation Condition Index)
• soil-moisture indices

• hydrological indices: SFDI (stream flow), GWDI (groundwater) and RSI (reservoir storage)

• Grading [2]:

• severe if 2 of the 3 chosen impact indicators are in the severe category

• moderate if 2 of the 3 are in the moderate category

• Step 3: Ground truthing (checking on the ground) [2]

• done in a random 10% of affected villages, preferably with a smartphone app

• a crop loss of 33% or more qualifies for a drought declaration

• Deadlines [2]:

• kharif drought: by 31 October (early declaration possible in August)

• rabi drought: by 31 March (early declaration possible in November or December)

• Money [2]:

• NDRF (National Disaster Response Fund) help is mainly for severe drought
• moderate drought is handled from the SDRF (State Disaster Response Fund)
• if SDRF money runs out, a state may seek NDRF help even for moderate drought

Where it occurs

• How much of India is affected (NCERT):
• about 19% of the area and 12% of the people are hit by drought every year

• about 30% of the area is drought-prone, affecting about 50 million people

• Why central and western India are prone:

• Rain shadow (the dry side of a mountain, away from the moist wind): the Western Ghats take most of the south-west monsoon rain, so the interior Deccan stays dry.

• Monsoon margins (places at the outer edge of the monsoon's reach), such as Rajasthan and Gujarat, where rain is low and very uncertain.

• Drought zones (NCERT Figure 6.7):

Zone	Areas
Extreme	Most of Rajasthan west of the Aravalis: the Marusthali (Thar desert) and Kachchh (Gujarat). Jaisalmer and Barmer get under 90 mm of rain a year.
Severe	Eastern Rajasthan; most of Madhya Pradesh; eastern Maharashtra; interior Andhra Pradesh and the Karnataka plateau; northern interior Tamil Nadu; southern Jharkhand; interior Odisha
Moderate	Northern Rajasthan; Haryana; southern Uttar Pradesh; the rest of Gujarat; Maharashtra except Konkan; Jharkhand; the Coimbatore plateau (Tamil Nadu); interior Karnataka

• Chronic drought regions (where drought keeps coming back):
• Marathwada: central Maharashtra, in the rain shadow of the Western Ghats

• Bundelkhand: southern Uttar Pradesh and northern Madhya Pradesh. It has a hard rock base, thin soils and uncertain rain.

• Programmes for dry lands:

• Drought Prone Areas Programme (DPAP), started in 1973-74

• Desert Development Programme (DDP), started in 1977-78, for hot deserts (Thar) and cold deserts

• The world link: El Niño (a warming of the central and eastern Pacific Ocean) tends to weaken the Indian monsoon. IMD's long-range forecast of 13 April 2026 expected below-normal rain (90-95% of LPA, the Long Period Average) and a likely El Niño [2].

• Who supplies drought data [2]: rainfall from IMD; crop condition from satellites by MNCFC, NRSC and the State Remote Sensing Centres; stream flow from CWC and India-WRIS; groundwater from CGWB.

Don't confuse with

• Meteorological vs hydrological drought: meteorological drought is a shortage of rain, and it comes first. Hydrological drought is a shortage of water in aquifers, lakes and reservoirs, and it comes after meteorological drought, not at the same time.
• Drought vs aridity (desert climate): aridity is a permanent feature of a dry climate. Drought is a temporary shortage of water compared with what is normal for that place. That is why even a wet region can face drought.
• Drought vs flood, cyclone or earthquake: drought is a slow-onset hazard that builds up over weeks and months. The others strike suddenly.
• Akal vs trikal: akal is a shortage of food grain only. Trikal is a shortage of grain, fodder (trinkal) and water (jalkal) all together, which is the worst kind.

Prelims Hooks

• IMD seasonal rain deficit: 26-50% = moderate and more than 50% = severe meteorological drought.
• An area with more than 30% of its gross cropped area irrigated is not counted as drought-prone.
• Trap: the Coimbatore plateau and interior Karnataka are in the moderate zone, but eastern Rajasthan and the Karnataka plateau are in the severe zone. Jaisalmer and Barmer (under 90 mm of rain) are in the extreme zone, west of the Aravalis.
• Akal = grain, trinkal = fodder, jalkal = water, trikal = all three.
• DPAP started in 1973-74 and DDP in 1977-78.
• Drought Manual: the mandatory indicators are rainfall deviation or SPI, plus a dry spell. A crop loss of 33% or more qualifies for a declaration. Kharif drought must be declared by 31 October and rabi drought by 31 March [2].

Mains Points

• Why droughts are so common in India (GS-I):
• The monsoon is uncertain, and the rain-shadow interior and the monsoon margins are dry.
• Groundwater is pumped out faster than rain refills it.

• So a short rain shortage quickly turns into a hydrological drought, mainly in Marathwada, Bundelkhand and Rajasthan.

• Impacts and the shift from relief to risk reduction (GS-III):

• Akal, trinkal and jalkal hit farm incomes and livestock. People migrate in distress, food prices rise, and contaminated water spreads gastroenteritis, cholera and hepatitis. The poor and landless suffer most.

• In line with the Sendai Framework (2015-2030), the 2016/2020 Drought Manual uses satellite, soil-moisture and hydrological data. This makes declarations faster and fairer, and links the money to the NDRF or SDRF [2].

• Long-term fixes:

• Rainwater harvesting and watershed development under Jal Shakti Abhiyan: Catch the Rain. Its works fall under five heads: water conservation and rainwater harvesting, renovation of traditional water bodies, reuse and recharge structures, watershed development, and intensive afforestation [3].
• MGNREGS gives paid work in drought years, which stops distress migration and builds ponds and check dams. Other fixes are drought-resistant crops and finding new aquifers.
• Inter-basin transfer and river interlinking can move water from surplus areas to dry ones, but their ecological and legal costs need careful checking.

Related concepts

• Meteorological drought
• Agricultural drought
• Hydrological drought
• Ecological drought
• Drought-prone areas of India
• Akal, trinkal, jalkal and trikal
• Drought mitigation

Read more

• Droughts: types, drought-prone India and mitigation