Drought is a creeping phenomenon with no universal definition. The distribution of water on the earths surface is not even. Drought definition, a period of dry weather, especially a long one that is injurious to crops. Droughts are the secondmost costly weather events after hurricanes. It differs from the aforementioned types of drought because its occurrence depends on the time and space processes of supply and demand to identify or classify droughts. It can be a major weather event that affects animals, plants, and people. Towards a compendium on national drought policy towarrds. Drought definition is a period of dryness especially when prolonged. Take your hr comms to the next level with prezi video. Irrigation definition of irrigation by merriamwebster. Conceptual definitions of drought offer a general idea or concept of drought. It is often difficult to decide when a drought started and sometimes when it ends too. It has been defined in many ways by various disciplines because the characteristics of drought and its impacts reflect the climate and societal characteristics of the region affected.
For example, only six days without rain is a drought in bali. Drought introduction slide 3 moisture imbalance and drought drought is when crops need more water than is availablerecharge of aquifers, lakes, and reservoirs is insufficient to provide irrigation waterprecipitation is too low at critical timesprecipitation or snow pack is not sufficient to restore ground water. Zolotokrylin encyclopedia of life support systems eolss agricultural, and hydrologic phenomena. Agricultur a agriccult dorhonto drought management. Wherever there is a shortage of rain over a long period of time, there is drought. Drought definitions conceptual definitions, formulated in general terms, help people understand the concept of drought. Considerable work is ongoing in terms of integrating livelihoods knowledge into drought management. Drought is a reduction in precipitation over an extended period. Drought cannot be defined in terms of inches of rainfall or number of days without rain, since it is determined by such variable factors as the distribution in time and area of precipitation during and before the dry period.
A drought or drouth is an event of prolonged shortages in the water supply, whether. A drought is a long period of time during which no rain falls. Drought article about drought by the free dictionary. For each week, the drought monitor labels areas of the country according to the intensity of any drought conditions present. For the application of interest, whether it is the condition of a water supply system, the requirements for irrigation or the sustainability of an ecosystem, a quantitative expression for the state of drought is required. Hydrologists define drought as an extended period of less precipitation and stream flow. For example, drought is a protracted period of deficient precipitation resulting in extensive damage to crops, further.
Because drought affects so many economic an d social sectors, scores of definitions have. Regardless of a drought s stage, there are short and long term consequences with any drought because of nature and societys dependence on water. The terms drought event definition and drought index are frequently being confused. Drought definition and meaning collins english dictionary. Defining these triggers is an inseparable part of planning for and responding to droughts. Irrigation definition is the watering of land by artificial means to foster plant growth. Drought conditions make it unsuitable for plants and vegetation cover to survive. The lack of adequate precipitation, either rain or snow, can cause reduced soil moisture or groundwater, diminished stream flow, crop damage, and a general water shortage. Drought is a creeping phenomenon with no universal definition definitions are region and application impact specific. Free definition, enjoying personal rights or liberty, as a person who is not in slavery.
Examples of drought management in the mediterranean. Faos work on drought aims to build societal capacities for drought risk management. Different sets of people have different definitions of drought. Background and brief overview for at least the last three years, colorado has been in the grip of a serious drought. It is a serious problem for farmers and for the people who depend on the crops they produce. Besides, fertile lands are lost as a result of drought, and in consequence, desertification sets in. Afghanistan drought risk management strategy reliefweb. A drought or drouth is an event of prolonged shortages in the water supply, whether atmospheric belowaverage precipitation, surface water or ground water. Droughts synonyms, droughts pronunciation, droughts translation, english dictionary definition of droughts. Persisting over months or years, drought can affect large areas and may have serious environmental, social and economic impacts. A long period of abnormally low rainfall, especially one that adversely affects growing or living conditions.
California drought presentation by aden matthews on prezi. Also, based on faos definition of a water scarce country as having. Pdf the objective of this study is to provide a description of the background of the definition and the available methods characterizing point and. State, rural society and institutional change since the great leap famine.
Contractiondesiccation cracks in dry earth sonoran desert, mexico. Mar 28, 2020 drought countable and uncountable, plural droughts a period of unusually low rainfall, longer and more severe than a dry spell. List of designated drought disaster counties pdf, 161 kb u. Definitions of drought must be region and application or impact specific. Since drought differs so much from place to place, there is no absolute figure that defines a drought. They use the previous 30 years of rainfall to create the. This rain shortfall creates a water shortage which damages crops, livestock, and other human activities. A drought is an extended period of months or years when a region notes a deficiency in its water supply whether surface or underground water. It can have a substantial impact on the ecosystem and agriculture of the affected region and harm to the local economy.
An application of the proposed drought definition procedure is presented for the case of a frequency analysis of multiyear hydrologic droughts. Pdf this chapter is focused on drought mitigation practices. Mar 31, 2020 the definition of drought varies from place to place. Many indices and indicators are available to assist in the quantitative assessment of drought severity, and these should be evaluated carefully for their application to each region or location and sector. While drought is a natural phenomenon, whose impacts can be exacerbated by human activities that are not adapted to the local climate, land degradation is the. The bureaus drought maps highlight areas considered to be suffering from a serious or severe rainfall deficiency. History suggests that severe and extended droughts are inevitable and part of natural climate cycles. The worst drought years were 1891, 1911, 1921, 1931, 1936, 1946, 1954, 1957, 1967, and 1971. Drought monitor is a weekly map of drought conditions that is produced jointly by the national oceanic and atmospheric administration, the u. This year, as conditions became extreme, the states residents have felt its full effect and demanded that public officials and water managers respond. Drought most often strikes the lands along the middle and lower volga regions and the basin of the ural river. Improving drought response in pastoral areas of ethiopia. Drought impacts are a key indicator of vulnerability. Types, causes and effects of droughts earth eclipse.
Once these triggers are defined, a region is much better able to estimate the costs, expected frequency, and risks of drought response. These classes are assigned by first examining rainfall periods of three months or more for selected places throughout australia to see whether they lie below the 10th percentile lowest 10% of records. Maos secret famine the first full account of the tragedy that claimed over 30 millions victims. They are sometimes said to be in a permanent drought. This is usually called a drought index and allows a farmer, a manager or policymaker to objectively analyse a system and make quantitative management. Drought risk management background drought is a natural phenomenon that has drastic implications on human lives, food insecurity and natural resources degradation. A drought index is often a single number characterising the general drought behaviour at a measurement site, whereas a drought event definition is applied to select drought events in a time series including the beginning and end of the droughts. The objective of this study is to provide a description of the background of the definition and the available methods characterizing point and regional droughts. The 2018 drought directly affected more than twothirds of afghanistan 22 out of total 34 provinces with around 10. Drought leads to water shortages affecting agriculture, with social consequences such as famine, hunger, and migration. The most common cause for drought is failure of rains. An area experiencing drought is assigned a score ranging from d0, the least severe drought, to d4, the most severe. Extensive literature is available on droughts with respect to definition, methods of analysis and management procedures.
Generally, this occurs when a region receives consistently below average precipitation. Problems associated with drought can have economic, environmental, and social impacts on both the areas where they occur and areas that have relations with those where the drought happens. Review of literature will always help one to have information and. Drought simple english wikipedia, the free encyclopedia. Crop farmers describe drought as the absence of moisture, which inhibits crop growth. Drought characteristics and management in the caribbean. Instead, scientists measure it as a deviation from average rainfall. Drought, climate change and potential agricultural productivity. It indirectly causes job and business losses in the farmers communities and around the.
Listen to the audio pronunciation in the cambridge english dictionary. Day 1 drought concepts and how they are represented in the. I will first outline a weak definition of the term democracy and a discussion of the definition of famine as used in this article. In general, drought is defined as an extended period a season, a year, or several years of deficient rainfall relative to the statistical multiyear average for a region. Approximately every three years, the ussr loses up to 1. Jan 23, 2020 regardless of a drought s stage, there are short and long term consequences with any drought because of nature and societys dependence on water. As a result there is not enough water available through hand pumps, wells and other traditional sources that depend on underground reserves of water. The current drought and the future of water management in colorado a.
Droughts definition of droughts by the free dictionary. Drought and desertification are closely related phenomena. A drought can last for months or years, or may be declared after as few as 15 days. In this paper, drought events are considered to be composed of duration, magnitude average water deficiency, and severity cumulative water deficiency. When a certain drug is in limited supply or unavailable in your city or hood.
The impacts of drought first order impacts such as food security concerns and second order impacts such as increasing food imports from abroad produce a range of effects for many in society benson and clay, 1998. The now unproductive suffix th and its alternate form t were formerly used to derive. Summaries and detailed data are published free of charge at this. Droughts pdf download types of droughts and factors. The drought contingency plan plan is a framework of forwardleaning planning for scenarios and objectives, managerial and technical actions, and potential response systems in order to prevent, or better respond to, a drought related emergency or critical situation. Drought is the consequence of anticipated natural precipitation reduction over an extended period of time, usually a season or more in. Droughts article about droughts by the free dictionary. Department of agriculture, and the national drought mitigation center ndmc at the university of nebraskalincoln. A drought is a period of time when an area or region experiences belownormal precipitation. The latter pronunciation, therefore, is not a mispronunciation of drought.
This study investigated and analysed the preparedness, impact of and. Civil and environmental engineering, princeton university, princeton, nj 2department of applied physics and applied mathematics, columbia university, new york, ny. Its effects often build up slowly over a long period of time and may last from months to years after rain resumes. Although droughts can persist for several years, even a short. Drought is a major disaster in south africa in terms of total economic loss and number of people affected. However, dozens of more specific drought definitions are used around the world that are defined according to the lack of rain over various time periods, or measured impacts such as reservoir levels or. For example, agricultural and hydrological droughts appear when the water shortage significantly affects the agricultural or hydrologic activity. Drought meaning in the cambridge english dictionary. Desertification is whereby the lands become infertile and bare, frequently as a result of overgrazing and is exacerbated by drought which makes it difficult for.
The areas of agricultural, urban and forest areas will be provided for droughtaffected zones on an example that. How to pronounce drought in english cambridge dictionary. About 60% of subsaharan africa ssa is said to be vulnerable to drought. Drought, climate change and potential agricultural productivity justin sheffield1, julio e. Famine started with severe drought destitution caused by millions of armed men, crushing exactions from landlords, enforced taxation and poor government intl famine relief commission. Drought definition of drought by the free dictionary. Causes and current understanding congressional research service summary drought is a natural hazard with potentially significant economic, social, and ecological consequences. Meteorologists define drought as a prolonged duration without rain. Droughts pdf download types of droughts and factors the term drought in simple words is the absence of water for a long period of time, at a place where it is considered abnormal as compared to its usual conditions. Drought is one of the most frequent and devastating phenomena that occur in south africa. Drought is a period of time without substantial rainfall that persists from one year to the next. Many indices and indicators are available to assist in the quantitative assessment of drought severity. The tanks, wells and similar underground water reserves remain unchanged.