A drought year is defined by the Indian Meteorological Department (IMD) as one in
which the overall rainfall deficit is greater than 10% of the long-term average and more than 20% of the agricultural land is affected. People’s perceptions of drought vary based on
human influences and how they interact with natural dry conditions. There are various types of drought:
- Meteorological drought: It is determined by the degree of dryness (as compared to “normal” or “average”) and the length of the dry spell. A meteorological drought is usually followed by a drought. The general absence of moisture in the weather like precipitation, and the play of other weather conditions, for example, high temperatures and dry winds etc.
- Agricultural drought: Agricultural drought refers to a meteorological (or hydrological) drought that has a negative influence on agriculture, such as precipitation shortages, soil water deficits, lower groundwater or reservoir levels needed for irrigation, and so on. As atmospheric moisture is reduced, soil moisture is affected and, as a result, crops, animals, and evapotranspiration are affected. This kind of drought is also referred to as soil-moisture drought.
- Hydrological drought: A hydrological drought occurs when there is a prolonged period of low precipitation, which contributes to water scarcity (streamflow, lake and reservoir levels, groundwater), which can have serious socio-economic repercussions. During these periods, the supply of surface and groundwater is inadequate, often due to inadequate rainfall and unrestrained usage of surface water for agricultural purposes, energy production, and other uses.
- Ecological drought: A natural or (managed) ecosystem will experience an ecological drought when its primary productivity falls significantly due to reduced precipitation. Damage will be caused to the ecosystem as a result of ecological distress.
- Socioeconomic drought: Socioeconomic drought is a combination of all the above types of droughts. It occurs when precipitation is insufficient to adequately meet human activities. This condition aggravates supply problems such as food, water and energy shortages. Population growth and unrestricted consumption can further exacerbate droughts by putting greater stress on limited water supplies. These kinds of droughts take a long time to get going, and they take a long time to recover from.
Drought Prone Areas in India:
- A basic understanding of the drought issue in India requires consideration of some basic facts. For instance, India has an average annual rainfall of nearly 1160 mm; no other nation has a similar annual average; however, the annual variation is substantial.
- 21% of the area receives less than 700 mm of rainfall annually, making such areas the hotspots of drought. The Southwest monsoon receives over 80% of rainfall in less than 100 days, and the geographic spread is uneven. Because of insufficient rains and an unfavourable land-man ratio, farmers in large parts of the country practice rain-fed agriculture. A decade of insufficient rainfall in the peninsular region necessitates irrigation using groundwater, which aggravates the situation in the long run since groundwater withdrawal exceeds replenishment. There is a constant decline in the per capita availability of water in India. Droughts in India can be categorized as follows:
- Conditions of Extreme Drought: This category encompasses approximately 12% of all drought-prone areas. Gujarat, Western Uttar Pradesh, North-West Madhya Pradesh, and Western Rajasthan are among them.
- Conditions of severe drought: It spans around 42% of the whole drought-prone region, which includes the leeward side of the Maidan plateau, Andhra Pradesh’s Rayalaseema and Maharashtra’s Marathwada and Vidarbha.
- Conditions of moderate drought: It prevails over around 46% of the total drought-prone region, i.e., Central-north Madhya Pradesh, Chhota Nagpur, Odisha, Jammu and Kashmir and central-east Tamil Nadu.
Vulnerability to drought is aggravated by a region’s risk of water shortage and the exposure of the communities to the problems arising therefrom. If nations and regions are to make progress in reducing the serious consequences of drought, they must improve their understanding of the hazard and the factors that influence vulnerability.