Drought occurs when a region receives consistently below average precipitation over an extended period, resulting in water shortages. Drought can have substantial impacts on agriculture and regional economies. In India, drought has historically led to tens of millions of deaths from famines in the 18th-19th centuries. Indian agriculture is heavily dependent on the summer monsoon, and failure of the monsoons can result in below average crop yields, impacting parts of India like Maharashtra, Karnataka, Haryana, Gujarat, and Rajasthan. The document then discusses various physical and climatic factors that can cause drought, as well as human impacts like overuse of water resources and depletion of forests.

1. DROUGHT
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Indian case studies

2.  Drought is an extended period of months or years when a region notes a deficiency
in its water supply whether surface or underground water. Generally, this occurs
when a region receives consistently below average precipitation. It can have a
substantial impact on the ecosystem and agriculture of the affected region.
Although droughts can persist for several years, even a short, intense drought can
cause significant damage and harm the local economy.
 Many plant species, such as cacti, have adaptations such as reduced leaf area and
waxy cuticles to enhance their ability to tolerate drought. Some others survive dry
periods as buried seeds. Semi-permanent drought produces arid biomes such as
deserts and grasslands. Most arid ecosystems have inherently low productivity.
2
We can feel the dryness in your throat. The land is barren and covered in thin
dust. cracks appear in the earth. This is drought, when water is so scarce that the
existence of life becomes threatened. How do humans effects from drought?
INTRODUCTION
Drought Indian case studies

3.  Physical aspects also used to classify
drought. They clubbed into three major
groups:
 Metrological
 Agriculture
 Hydrological
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4.  1. Less rainfall:
 2. High Air pressure: When there is high air pressure, air falls instead of
rising. With the air pressing down in a high pressure zone, no currents of water
vapor are carried upward. As a result, no condensation occurs, and little rain
falls to earth.
 3. Low air pressure: Low-pressure systems see more cloudy, stormy weather.
Usually, however, we experience both high- and low-pressure systems.
 4. Monsoon role: Usually, summer winds known as monsoons carry water
vapor north from the Indian Ocean inland, providing desperately needed rain.
 Sometimes, however, instead of blowing from north to south, they blow east to
west. When that happens, the vapor doesn’t leave the Indian Ocean and many
people suffer from the resulting droughts.
 5. Water Vapor role: Droughts occur because water vapor is not brought by
air currents to the right areas at the right times. Water that evaporates from the
oceans is brought inland by wind to regions where it is needed. However,
sometimes those winds are not strong enough.
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5.  6. Moisture: In some states, moisture is carried up from the ocean by blowing winds.
This moisture is then pushed by other winds until it reaches the location. However, if
the winds don’t blow at the right time, in the right direction, or with enough force, the
moisture falls in other areas and suffers from drought.
 7. Mountains region wind: Mountains can prevent wind from blowing moisture to
needed regions. As air is moving past a mountain range, it is forced to rise in order to
pass over the peaks. However, as the air rises, it becomes colder and the vapor
condenses into rain or snow.
 When the air mass finally makes it over the mountain, it has lost much of its vapor.
This is another reason why many deserts are found on the side of a mountain facing
away from the ocean. This phenomenon is known as the rain shadow effect.
 8. Rainfall pressure: Generally, rainfall is related to the amount of water vapor in the
atmosphere, combined with the upward forcing of the air mass containing that water
vapor. If either of these are reduced, the result is a drought.
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6.  9. Global warming: Human activity can directly trigger exacerbating
factors such as over farming, excessive irrigation, deforestation,
and erosion adversely impact the ability of the land to capture and hold
water.
 10. Decline in groundwater : India has seen a sharp decline in
groundwater levels, leading to a fall in supply, saline water
encroachment and the drying of springs and shallow aquifers. Around
50% of the total irrigated area in the country is now dependent on
groundwater, and 60% of irrigated food production depends on
irrigation from groundwater wells.
 11. Depletion of forest : The rapid depletion of forest cover is also
seen as one of the reasons for water stress and drought. India has a
forest cover of 76 million hectares, or 23% of its total geographical
area – much lower than the prescribed global norm of 33%.
 12. Rainwater harvesting : Combined with these and a host of other
factors – poor irrigation systems, pressure from the increasing
industrial use of water is the appalling indifference displayed towards
rainwater harvesting. Little has been done over the years to drought-
proof the country, when community based rainwater harvesting
measures could easily accomplish this feat.
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7. 14. Rainwater harvesting : Combined with
these and a host of other factors – poor
irrigation systems, pressure from the
increasing industrial use of water is the
appalling indifference displayed towards
rainwater harvesting. Little has been done
over the years to drought-proof the country,
when community based rainwater harvesting
measures could easily accomplish this feat.
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8.  Meteorology
 · Inadequate monsoon rainfall.
 · High temperature & evaporation, wind speed.
 · Unseasoned rains & fog / snowfall.
 Water Resources
 · Inadequate water availability, high water loss in storage & distribution,
utilities.
 · Over exploitation of surface & ground water.
 Agriculture- Crop Yield
 · Shift in agricultural practices(low to moderate water demand crops to
high crops).
 · Crop damage due to rain & snow / pest.
 Population
 · High greater rate of human & animals.
 · Location of high water consuming milestones at semi arid / arid regions.
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9. Drought in India has resulted in tens of millions of deaths over the course of the
18th, 19th, and 20th centuries. Indian agriculture is heavily dependent on the
climate of India: a favorable southwest summer monsoon is critical in securing
water for irrigating Indian crops. In some parts of India, the failure of the
monsoons result in water shortages, resulting in below-average crop yields.
This is particularly true of major drought-prone regions such as southern and
eastern Maharashtra, Karnataka, Haryana , Gujarat, and Rajasthan. In the
past, droughts have periodically led to major Indian famines, including the
Bengal famine of 1770, in which up to one third of the population in affected
areas died; the 1876–1877 famine, in which over five million people died; and
the 1899 famine, in which over 4.5 million died.
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10. 10Drought Indian case studies

11. 11Drought Indian case studies

12. 12
0
200000
400000
600000
800000
1000000
1200000
1400000
1600000
1979 1982 1983 1987 2013
Area Affected in India by Drought
Area Affected in (Km
sq.)
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13. 13
0
50000000
100000000
150000000
200000000
250000000
300000000
1979 1982 1983 1987 2013
People affected in India by Drought
People affected
Drought Indian case studies

14. Drought
14Drought Indian case studies

15. (115075)
(115076)
15Drought Indian case studies