Introduction

"Drought" denotes the meteorological, agricultural, environmental, climatic, social, economic, and political consequences of a gap between the water availability and demands for the needs of domestic, irrigational, industrial, commercial, and recreational consumption in an area over an extended period. As these demands vary from region to region and depend on too many parameters such as quantum of rainfall, geological and soil characteristics, land use, population, economic activity, climatic conditions, population and culture, drought conditions of an area may not have characteristics of some other region. Such variability makes it difficult to detect.

Drought can be defined by rainfall amounts, vegetation conditions, agricultural productivity, and soil moisture, levels in reservoirs, and streamflow or economic impacts. In the most basic terms, drought is a significant deficit in moisture availability due to lower than normal rainfall. thus, defining drought, mapping drought-affected regions, and selecting mitigation measures to be adopted have all been tenuous tasks which in turn, together, make management of this geohazard a most dreaded one, often with unsatisfactory results. However, drought is the most serious threat to humanity, the environment, and the economy. since the year 1980, there have been 384 drought events the world over, which killed 5, 58,215 people at an average of 21,470 deaths per year, affected more than 151,80,36,968 people, and inflicted economic loss to the tune of 29,28,778 us dollars per year. World disasters report (1994), conclude that except for civil strife droughts caused more social disruption than any other natural or non-natural disaster during recent history. World health organization estimates that out of the total death toll resulted from natural disasters, the drought alone had contributed towards half of it. These observations necessitate a thorough understanding of the nature of droughts.

Definition of drought

The word Drought is always difficult to define because it's often used in quite one context. A deficiency of precipitation from expected or normal that extend over a season or longer period of your time results in the Water supply that is insufficient to meet the needs of human activities and also the Environment. The distribution of water on the earth's surface isn't even, some places have much freshwater. Some places have little water. A drought is an extended period of months or years when a region notes a deficiency in its water supply. Droughts can persist for several years, even a short, intense drought can cause significant damages. Generally, it occurring when a Region receives consistently below-average precipitation. A Drought is a natural disaster that usually takes place slowly. Droughts can also be triggered by deforestation, global warming, and diverting rivers.

The difference between drought and famine

The main difference between Drought and Famine is that Drought is an extended period when a region notes a deficiency in its facility and Famine is a widespread scarcity of food followed by regional malnutrition, starvation, epidemic, and increased mortality.

Concepts about drought:

Farmer: lack of moisture affecting his crops is drought.

Weathermen; a prolonged period without rain could be called drought.

Hydrologist; a prolonged period of less stream-flow and precipitation could be called drought

Types of droughts:

Meteorological droughts: This is usually based on long-term precipitation departures from normal, though high temperature often plays a role. Generally defined by a lack of moisture in the weather e.g. dry wind, high temperature, and so on. It is usually an indicator of a potential water crisis if the conditions are prolonged. Meteorological droughts can begin and end immediately.

Hydrological droughts: When surface water is deficient and groundwater supply in a region, often as a result of less precipitation, excessive reliance on surface water for farming. A hydrological drought does not usually occur at the same time as a meteorological drought. In a way, this decline in the quantity and quality of surface and sub-surface water is the effect of meteorological droughts.

Agricultural drought: This is when atmospheric moisture is reduced to the extent that the soil moisture is affected. Here the crops and animals are affected and evapotranspiration is also affected. This type of drought doesn’t depend only on the number of rainfalls where water is used carelessly for irrigation and another purpose. It is the effect of meteorological droughts.

Socioeconomic drought: This is the condition when some supply of goods and services such as energy, food, and drinking water are reduced by changes in meteorological and hydrological conditions. Sometimes it is even made worse by the excessive demand of growing population for such goods, its create stress on little water available. It takes a very long time for this kind of drought to be in full gear, and a long time to recover from it.

Causes of drought

As droughts are the result of acute water shortage due to lack of adequate rain over extended periods affecting environmental, agricultural, industrial, commercial, recreational, economic, social, political, and other human endeavors, many parameters including but not limited to, namely, climatic cycles, geographic Locations, land use, soil and other physical, geological, environmental systems, vegetation and population patterns, type and intensity of economic activity are all involved, thus making accurate targeting of the exact cause of establishment of drought conditions in an area a difficult task. In addition, the estimation of the quantum of the contribution of all these causes is still more complex. Such intrinsic complexity is the reason why most often drought relief and mitigation measures are destined to be less successful.

The following paragraphs present few generalizations.

Rainfall or precipitation deficiency: No rainfall or precipitation for a prolonged time of period, when a region goes for a long t time of period without rain, the situation leads to dry conditions and water deficiency which qualify as drought.

Human causes: Human activities such as deforestation, construction, and agriculture negatively affecting the water cycle. Trees and vegetation are important to cover essential for the water cycle as it helps to limit evaporation, store water and attract rainfall.

Drying out of surface water flow: the demand for water supply has increased resulting in drying out surface water; this may result due to high population growth and human activities such as irrigation systems and hydroelectric dams can diminish significantly the amount of water flowing downstream to the other areas.

Global warming: human actions have contributed to more and more emissions of gags resulting in the continuous rise of the earth’s average surface temperature. Evaporation and transpiration levels have risen and high temperatures have led to wildfires extended dry spell periods.

Effects of droughts:

Health effects: bad air: droughts can reduce air quality, during droughts, dry soil and wildfires increase the amount of air born particles, such as pollen and smoke may cause respiratory problems, allergy, and eyes irritation. Valley fever: the fungal infections are increased when spores in the soil become airborne and inhaled. E .g coccidioidomycosis or valley fever, ranging symptoms, fever, chest pain, coughing, and muscle aches. Thirst, hunger: all living things need water for survival. Droughts reduce crop production. Water scarcity. Waterborne diseases: increase in disease transmitted by insects which are spread by mosquito, linked with droughts. E.g. west Nile virus. Roughs to be in full gear, and a long time to recover from it.

Agricultural effects: Agricultural land is widely affecting by droughts. The most immediate effect of drought is a fall in crop production, due to inadequate and poorly distributed rainfall. Death of vegetation tees. Loss of agricultural lands due to droughts.

Environmental impacts: The surroundings are directly compact by drought. Drought will affect water sources, land, fish, and life and plant communities. Drought may result in lower water levels in reservoirs, lakes, and ponds, in addition to reduced streamflow in rivers. This decrease in offered water may also cause a discount of some wetlands, groundwater depletion, and even impact water quality (e.g. salt concentration will increase). Inadequate installation may result in reduced ability for soils to support crops, associate degree enlarged quantity of dirt because of waterlessness, erosion, and a larger likelihood of wildfires because of the dry landscape. A scarcity of water and reduced ability for soil to support crops will affect fish, animals, and flowers. Life environs could become degraded as a result of poor soil quality and inadequate water could affect plant growth, and there might not be enough beverages for animals. There may additionally be stress placed on species and a loss of diversity within the affected space.

Economic losses: Economic impacts range from direct losses in the broad agricultural and related sectors (forestry and fishing) to losses in recreation, banking, and energy sectors. In the agricultural industry, dry conditions can damage the crops, negatively impacting farmer income. Crop loss also impacts consumers. Loss of revenue to local state, and federal government.

Mitigation steps:

Construction of dams and their associated reservoirs helps in in additional supply of water at drought time.

Desalination: (removal of salts and minerals from saline water), use of seawater for irrigation, and other consumption processes.

 

Drought monitoring: continuous observation of rainfall levels and comparisons with current usage levels can help prevent man-made droughts.

Land use: carefully planned crop rotation can help to minimize erosion and allow the farmer to plant less water-dependent crops in drier years.

Rainwater harvesting: collection and storage of rainwater from roofs or other suitable catchments. The rainwater may be then used for garden irrigation and other purposes

Outdoor water-use restrictions: bans and other

Restrictions are put into effect that restrict outdoor use of water supplies. E.g. car washing, irrigation of lawns, recreational uses such as filling swimming pools. Regulating the use of sprinkles buckets on outdoor plants and other water-intensive home tasks.

Recycled water: former wastewater (sewage) that has been treated and purified for reuse.

 

About the Author: Ihsan Ur Rahman is a student at Abdul wali khan university Mardan KPK. He is an environmental activist.

Editor name: Amina Shahzadi