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1. Group Members:
Muhammad Usman BAGF14E256
Abdul Majid BAGF14M069
Hamza Dildar BAGF14M045
Ahsan Shahzad BAGF14E268
Tayyab Boota BAGF14M081
DROUGHT

2. DROUGHT
Drought is defined as a
period in which a region has
a deficit in its water supply
whether surface or
underground water . A
drought can last for months
or years, or may be declared
after as few as 15 days.
Generally, this occurs when a
region receives consistently
below average precipitation.

3. DROUGHT
• A drought is an extended period of dry weather leading to extreme dryness.
• This results in a shortfall of water supply which has hydrological and
agricultural impacts.
• Drought is different from most other hazards as it develops slowly as a
creeping hazard.
• Aridity and desertification are associated with drought but they are not the
same.
• Drought is characterized by moisture level below normal for the area
affected.

4. SOME OF THE COMMONLY USED DEFINITIONS
(CONCEPTUAL) ARE:
• The World Meteorological Organization (WMO, 1986) - ‘drought means a
sustained, extended deficiency in precipitation.’
• The UN Convention to Combat Drought & Desertification (1994) -
‘drought means the naturally occurring phenomenon that exists when
precipitation has been significantly below normal recorded levels, causing
serious hydrological imbalances that adversely affect land resource
production systems.’
• The Food and Agriculture Organization (FAO, 1983) of the United
Nations - ‘the percentage of years when crops fail from the lack of moisture.’

5. DROUGHT CLASSIFICATION
• The droughts are generally classified (operational definitions) into
four categories (Wilhite and Glantz, 1985; American Meteorological
Society, 2004), which include:
Meteorological
Agricultural
Hydrological
Socioeconomic

6. METEOROLOGICAL DROUGHT
Meteorological drought is usually defined
on the basis of the degree of dryness (in
comparison to some “normal” or average
amount) and the duration of the dry period.
Definitions of meteorological drought must
be considered as specific to a region since
the atmospheric conditions that result in
deficiencies of precipitation are highly
variable from region to region.

7. AGRICULTURAL DROUGHT
Agricultural drought links various
characteristics of meteorological (or
hydrological) drought to agricultural
impacts, focusing on precipitation
shortages, differences between actual
and potential evapotranspiration, soil
water deficits, reduced groundwater or
reservoir levels, and so forth.

8. HYDROLOGICAL DROUGHT
Hydrological drought is associated with
the effects of periods of precipitation
(including snowfall) shortfalls on surface
or subsurface water supply (i.e.,
streamflow, reservoir and lake levels,
groundwater). The frequency and severity
of hydrological drought is often defined
on a watershed or river basin scale.
The effects of precipitation shortfalls on stream flows and reservoir, lake,
and groundwater levels.

9. SOCIOECONOMIC
Socioeconomic - This occurs when
physical water shortage starts to
affect people, individually and
collectively or, in more abstract terms,
most socioeconomic definitions of
drought are associated with the supply
and demand of an economic good.

11. DROUGHT - DAMAGES
Direct
 loss of income
 social dislocation
 famine/malnutrition/death
Indirect
 loss of rural and urban revenues
 fire hazard, loss of water access

12. DROUGHT CAUSES CAN BE CLASSIFIED IN
TWO WAY. THESE ARE…
• Global Warming
• Deficiency of Rainwater
• Weather (hot + dry)
• EL-NINO
• Soil Erosion
• Overpopulation
• Over cultivation
• Deforestation
• Over extraction of ground
water
• Politics
Natural Human made