3. Introduction
• Pakistan is an agricultural country and Rainfall is
the life line of Pakistan.
• Changes in rainfall pattern directly affect water,
agriculture and disaster management sectors.
• In most areas of the country, rainfall patterns have
become very unreliable and unpredictable.
4. • Moonsoon is the major source of rainfall in
Pakistan.
• The consequences of climate change and global
warming includes uncertainty in the occurrence
and intensity of precipitation.
• In this scenario, we would have to model our
national planning keeping in view the current era.
Scope of Project:
5. Data & Methodology
• In this investigation annual rainfall data of 19
national meteorological stations of Pakistan for
the period 2003-2012 has been incorporated.
• The stations are shown in the following figure.
6. Location of the Stations of Pakistan used in this investigation
/
7. The methods which are used in this investigation is
• Interpolation of annual rainfall (mm) of specific regions of
Pakistan by using Inverse distance weighted (IDW) in
ArcGIS.
• Co-efficient of variability of precipitation, in percentage.
Mathematical Relationship:
The following mathematical relationship is used to calculate
the coefficient of variability,
C.V= ( S.D/ R) × 100
Where
SD= Annual standard deviation
R= Annual Rainfall average (Camerlengo and Somchit, 2000).
8. Results and Discussion
Study of annual maps from interpolation gives important findings,
which are mentioned below,
Variation is increased from north to south; therefore our focus is
southern region. In lower KPK the situation is much safe regarding
the variability of rainfall. In lower Punjab, Northern Baluchistan
and Upper Sindh the maps has shown much fluctuation. In the
Lower Sindh region sharp variation are observed throughout the
period. In the Southern parts of Baluchistan the situation is
different from the northern half. In this region variation of rainfall
is very high.
19. Name of City Minimum annual rainfall
(mm) with year
Maximum annual rainfall
(mm) with year
Karachi 65.9 in 2004 465.6 in 2007
Hyderabad 52.4 in 2005 524.9 in 2006
Jacobabad 42.8 in 2009 583.8 in 2012
Nawabshah 30 in 2004 637.3 in 2011
Sibbi 56.8 in 2004 371.9 in 2007
Kalat 47 in 2010 449 in 2011
Jiwani 4 in 2011 173.2 in 2005
• In the following chart minimum and maximum annual rainfall of
few areas of Sindh and Baluchistan are mentioned,
20. When we plot a graph b/w variability coefficient and the
specific areas of Pakistan, we find following figure, which
shows that variability decreases from south to north in
general, except for extreme northern areas i.e. Gilgit
which reveals that forecasting is not a piece of cake in
southern half of country where variability is prominent,
but it is a challenging job for meteorologist.
22. Conclusions
• It was revealed in the study that most of the northern areas
have safeguarded while the southern half has suffered
throughout the year in terms of rainfall variability.
• Especially In the southern Baluchistan it has been observed that
rainfall remained fluctuating.
• Due to high variability in lower part of the country seasonal as
well as extreme events prediction is difficult.
• Increasing trend of precipitation variability over temporal and
spatial scales that climate variability will be more serious
challenge then climate change.
