Causes of droughts pdf

This kind of drought takes a long time to become severe and equally long time to recover from it. Jun 07, 2018 droughts are also exacerbated by low humidity, higher wind speeds, warmer temperatures, and greater amounts of sunshine. It can become dangerous to people and other animals. Droughts are natural events that occur in nearly all climate zones but with widely variable characteristics. Pdf east africa ea has been the primary focus for various drought studies in recent years. Changes in global atmospheric circulation can mean it doesnt rain much in an area. Exceptional drought conditions, which are expected only once per 50 or more years 1. It is mainly caused by low precipitation and high evaporation rates, but in regions. A high level of reflected sunlight, high albedo an unusual above average and strength of high pressure systems winds carrying continental, rather than oceanic air masses i. Droughts have plagued humankind throughout much of our history, and until recently they were often natural phenomena triggered by. Droughts can persist through a positive feedback, where very dry soils and diminished plant cover can further suppress rainfall in an.

Droughts are one of the scariest and deadliest natural calamities. Pdf definitions and effects of droughts researchgate. Droughts can be classified as meteorological, hydrologic, agricultural, and socioeconomic. The resultant effects of drought are exacerbated by human activities such as deforestation, bush burning, overgrazing and poor cropping methods, which reduce water retention of the soil, and improper soil. Types, causes and effects of droughts earth eclipse. The quantity of water vapor in the atmosphere pretty much impacts the precipitation of an area. The causes of drought in ea are diverse in nature, as this region is characterised by different geographical factors, regional oceanic circulations and coastal influences lyon, 2014. The causes of drought with particular reference to.

To be useful to decisionmakers, drought analysis reports must be timely and at appropriate spatial scales. The region is a focal point of important geographical areas including the turkana channel, east african highlands, lake victoria and the red sea trench lyon, 2014. There are a number of ways climate change may contribute to drought. Some arid areas of africa suffered from sustained reduction of rainfall over several decades of the late twentieth century, and recurring droughts. Sep 28, 2018 droughts occur in nearly all types of climate.

The magnitude and causes of global drought changes. Drought is a temporary feature of climate, an aberration. In the continental united states, the frequency and severity of droughts is expected to increase across the country during the next few decades. Drought is a continuous period of dry weather, when an area gets less than its normal amount of rain, over months or even years. The amount of precipitation at a particular location varies from year to. What is drought, its types, causes and effects natural.

Zolotokrylin encyclopedia of life support systems eolss precipitation over the land mostly outside arid areas. There are many smart people who say that we must slow down, that human society is a tumor on the body of our planet. Droughts and desertification key concepts you must know, or be able to do the following. Dec 20, 2018 hii ashish, some causes of droughts are 1. A drought can last for months or years, or may be declared after as few as 15 days. Is australias current drought caused by climate change. Some of which are, not having enough rain snow for a long period of time. Almost half of california is currently under exceptional drought conditions, which are expected only once per 50 or more years 1.

The amount of precipitation at a particular location varies from year to year, but over a period of years, the average amount is fairly constant. Jul 11, 2017 its very easy to assume climate change causes droughts, but they are complex extreme events that result from a combination of drivers. The causes of drought with particular reference to the sahel by john g. Of course, you wont be able to determine this as a cause for weeks, months, or even years into the future. As overall temperatures increase more water evaporates and severe weather conditions increase. A change in any one of these factors sets up a cyclical chain of events that can result in extreme climate conditions such as drought. In this article, we will see what drought is, its types, causes and effects drought is a temporary situation in which there is the rainfall is below normal that leads to water shortage. Countries that experience little rainfall have an even greater scarcity of rainfall. Warmer temperatures can enhance evaporation from soil, making periods with low precipitation drier they would be in cooler conditions. Strategic advance management in anticipation of a drought a drought that strikes a prepared farmer is a drought that will bring less loss and fear than expected. Table 1 presents definitions for these different types of drought. Informing the general public about the 201216 drought.

Causes because drought is defined as a deficit in water supply, it can be caused by a number of factors. During the drought of the 19911992 season, for example, maize production decreased by almost 75 percent leaving a large percentage of the population in dire need of food aid. The real reasons behind maharashtras manmade drought. Anticipatory management axel rothauge neudamm agricultural college, pbag 188, windhoek, namibia 2. The main causes for the changing pattern of droughts include climate variabilities and anthropogenic effects. Causes and consequences of the drought how this drought compares to past droughts depends on the timeframe, location, and metric of concern. Drought conditions can negatively affect agriculture, water supplies, energy production, and many other aspects of society. Landscapes and crops need more water to survive and overall the demand for water increases. While drought is mostly caused by irregular weather patterns, human activity can also be a cause of drought.

A longdrawnout period without rainfall can cause an area to dry out. Since agriculture is one of the main livelihood sources in india and it is depended on rainfall and water supply, a shortage in water affects agriculture badly resulting in famine and causes deaths on a. Including measures of confidence or uncertainty helps decision makers assess the credibility and usefulness of the information. A drought is a severe shortage of of water in a particular location. The causes of drought are complex, interrelated and, increasingly, manmade. Drought is one of the most frequent and devastating phenomena that occur in south africa. It is a complex issue full of uncertainties and controversies. It is the result of many causes including, global weather patterns, high pressure, the tropical outlook and other globalscale variables.

We can say that drought has many causes and there are various causes of drought. More specifically, there is concern that climate change may cause longer and severer spells of droughts. Droughts have extensive impacts on human beings, environment, water resources and agriculture. Causes and types of drought causes of droughts this can be triggered by. Majority of peasant people in nigeria rely on fuel wood as source of energy. A drought is a period of drierthannormal conditions that results in waterrelated problems. History suggests that severe and extended droughts are. Droughts often result in wildfires as the vegetation becomes dry and more prone to catching fire. This is why it is so important to consider changes in et when discussing water savings.

While droughts can be defined as a climate phenomenon, their impacts on humans and the. Arid and semiarid lands, where interannual rainfall variability is inherently. A case of the eastern cape and free state provinces of south africa author. Effects of drought on the environment water is essential to all life on earth and a shortage of this vital resource in the environment is bound to negatively affect all forms of life. Drought often creates a lack of clean water for drinking, public sanitation and personal hygiene, which can lead to a wide range of lifethreatening diseases. Wilhite, director school of natural resources the challenge for early warning systems. Well, that is exactly what happens during the droughts. Drought conditions and management strategies in zimbabwe. History suggests that severe and extended droughts are inevitable and part of natural climate cycles. During the drought of the 19911992 season, for example, maize production decreased by almost 75 percent leaving a large. Introduction drought is a sustained and regionally extensive occurrence of below average natural water availability. Pakistan is among the top ten countries adversely affected by climate change. Drought is a deviation from climate and is quite different from an arid region with low annual precipitation.

Of all the weatherrelated phenomena that can cause severe economic impacts in the united states, droughts come in second only to hurricanes. For example, overgrazing led to elevated erosion and dust storms that ampli. Droughts pdf download types of droughts and factors the distribution of water on the earths surface is not even. Droughts are a type of natural disaster that involves belowaverage precipitation or a severe water supply shortage over a sustained period of time. It can have a substantial impact on the ecosystem and agriculture of the affected region and harm to the local economy. Droughts have direct impact on domestic water supply andon water. However, a comprehensive analysis of droughts, including. If youre seeing rain or snow, but are seeing it in lighter amounts a drizzle here and flurries there, rather than steady rain or snow showers this can also signal a drought inthemaking. The western united states has experienced periods of horrible droughts throughout history, and climate change is blamed for producing more extreme weather variations in many other regions.

Meteorological drought usually precedes the other kinds of drought. All of these factors increase water loss from soils and plants. How do you incorporate impacts into a drought early warning system. Just take out some time and think about how much water you use in a day. Environmental rehabilitation involving the development of ecosystem services. Definitions and effects of droughts emphasis is given to the spatial variability over a region and the effects of drought over the water consumption and use sectors, such as domestic, download fulltext pdf download fulltext pdf the causes, effects and challenges of sahelian droughts. Studies conducted over the past century have shown that meteorological drought is never the result of a single cause.

An operational definition of drought helps people to identify the beginning, end, and degree of severity of a. If you live near a place where there is a river, a drought in that area can be caused by people upstream not getting enough water or moisture. During dry and hot weather periods, it is common to find dry and cracked earth without even a single shed of water or wet areas. Droughts pdf download types of droughts and factors. Socio economic impacts of droughts and economic instruments. Droughts are one of the most complex of all natural hazards, as it is difficult to determine their precise beginning or end. Causes, effects and mitigation 173 of trees due to drought. Sep 14, 2018 droughts often give rise to famines that can lead to the loss of millions of lives.

Agricultural droughts affect crop production or the ecology of the range. In addition, droughts can lead to other hazards, such as. 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. Droughts are caused by changes in land and sea surface temperatures, atmospheric circulation patterns and soil moisture content. Drought is a major disaster in south africa in terms of total economic loss and number of people affected. Drought is a vague and mysterious phenomena, and if we want to knowing it deeply and precisely it is not easy. Both desertification and drought are illdefined concepts, as will be explained here. Little or no precipitation is one of the major causes of a drought. They prognosticate that the discovery of fossil fuels was our pandoras box a box of devils and demons, and our tremendous reliance on them is our sword of damocles, a tragedy hanging over the head of the powerful. Jan 23, 2020 the farms themselves can also cause droughts to happen as the soil is depleted and therefore cannot absorb as much water, but they can be impacted by natural droughts as well. Causes, effects and mitigation 171 cover, all of which results in greater evaporation rates. To quantify the change in the characteristics of droughts in pakistan over the years, we have evaluated spatiotemporal trends of droughts in pakistan over the period 19022015 using standardized.

Crops and other plants need water to grow, and land animals need it to live. Mar 18, 2017 while this certainly can initiate drought conditions, oftentimes the onset of a drought is less noticeable. A drought or drouth is an event of prolonged shortages in the water supply, whether atmospheric belowaverage precipitation, surface water or ground water. Even though it is a natural disaster, it is one that can be prevented by man up to a certain extent. The farms themselves can also cause droughts to happen as the soil is depleted and therefore cannot absorb as much water, but they can be impacted by natural droughts as well. Drought is one of the natural disasters that can be reverted by nature itself. Assess which areas would be prone to droughts and desertification on both a global, regional and local scale. Deforestation, farming, excessive irrigation, erosion, and climate change due to global warming are all human causes of drought. In 2011, the year preceding the drought, maharashtra recorded an aboveaverage rainfall and most of the dams were full even today, maharshtra has the highest number of dams in the country. Meteorological factors can cause an area to get less rainfall than average. Drought definitions conceptual definitions, formulated in general terms, help people understand the concept of drought. Projected future aridity is presented based on recent studies and our analysis of model simulations. There are different papers and literatures that all of them have tried to recognize the causes of drought.

To a water manager, a drought is a deficiency in water supply that affects water availability and water quality. Lower than average levels of rainfall over a sustained period of time can dry the soil and and lead to crop. Droughts have claimed innumerable lives in india in the 18th, 19th and 20th centuries. Of late, droughts have been crippling the nation and have contributed to the already low lifeexpectancy levels and high levels of emigration. This study investigated and analysed the preparedness. Droughts take place whenever there is prolonged periods of rainfall deficiency for a season or more and usually when there is a lack of anticipated rainfall or precipitation. Meteorological drought occurs when there is a prolonged time with less than average precipitation. Droughts have extensive impacts on human beings, environment, water resources and. You drink water and use it to take a shower, brush your teeth and clean various items at home. To a hydrologist, a drought is an extended period of decreased precipitation and streamflow. Causes and current understanding congressional research service summary drought is a natural hazard with potentially significant economic, social, and ecological consequences. Understanding what causes a lack of precipitation helps shape policies and choices that have the potential to exacerbate. What are the effects of a drought on the environment.

The study of drought problems includes the following topics. Drought is a period of several months or even years of abnormal dryness due to belowaverage rainfall that causes a pronounced decrease in forage yield relative to what is expected in an average download fulltext pdf download fulltext pdf the causes, effects and challenges of sahelian droughts. Now can you imagine going without water for a week or longer. Are there places in the united states that experience drought. Lack or insufficient rainfall or precipitation this is the major cause of droughts in most regions. Drought causes and effects of drought extreme environments. Here is a list of the factors that trigger a drought. Drought and climate change center for climate and energy. In terms of snowpack, this drought is the worst in californias instrumental record. 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. In the deserts of the southwest, the average precipitation is less than 3 inches per year. Droughts have different physical characteristics society is dynamic so each drought event is superimposed onto societyimpacts reflect changing vulnerabilities does your country have a monitoring system for recording drought impacts.