Open Journal of Geology, 2012, 2, 294-300
http://dx.doi.org/10.4236/ojg.2012.24028 Published Online October 2012 (http://www.SciRP.org/journal/ojg)
Study of Hydrometeorology in a Hard Rock Terrain,
Kadirischist Belt Area, Anantapur District, Andhra
Pradesh
Katta Satya Sai Prasad, Purrumreddy Tirumala Ashok Kumar Reddy,
Nagam Balayerikala Reddy
Department of Geology, Sri Venkateswara University, Tirupati, India
Email: ksspsvu@gmail.com
Received May 25, 2012; revised June 21, 2012; accepted July 20, 2012
ABSTRACT
Hydrometeorological studies reveal that the study area comes under semi-arid zone with moderate drought conditions.
The rainfall confirms that erratic nature of rainfall in the study area. The rainfall data for 14 years of the study area re-
veal that only three years had sufficient rainfall and rest of the 11 years are drought-prone to varying intensities. It is
also observed that the area receives maximum amount of rainfall from south-west monsoon (June-December).
Keywords: Hydrometeorology; Rainfall Ratio; Drought and Hydrograph
1. Introduction
Geological factors, soils and vegetation influence the
distribution of water. However, it is mainly weather and
climate that form and sustain lakes and rivers create de-
serts and produce floods and droughts. This is because
the source of all fresh water is the rain and snow, which
falls from the clouds and the main loss of water, is what
returns to the atmosphere through the process of evapo-
ration. These are some of the facts of the hydrological
cycle that accounts for the never-ending movement of
water from the atmosphere to the ground by precipitation,
then to rivers, lakes and underground reservoirs and to
the sea. Most of the water vapor present in the atmos-
phere is derived from the salty seas by evaporation. The
hydrological cycle is nature’s great desalinization plant
by which saline seawater is converted into water vapor
and then into fresh waters that fall on the ground as rain,
and snow.
All the water that replenishes our rivers, lakes and
wells must pass through the atmosphere. Thus, the rivers
and groundwater on which we depend are controlled by
atmospheric events. It is obvious that the weather exerts
the major influence on the varying geographical distribu-
tion of water.
STUDY AREA:
The investigated area forms a portion of Kadiri schist
belt, lies between North Latitudes 14˚1 and 14˚10 and
East Longitudes 78˚05 and 78˚15, is one of the chroni-
cally drought affected areas of Anantapur district, An-
dhra Pradesh (Figure 1). It is a linear greenstone belt
situated in the eastern part of the Dharwar Craton and
southwestern part of the Cuddapah Basin.
2. Method
The rainfall data are collected form the Indian meteoro-
logical department of Anantapur and analyzing spatial
distribution of the rainfall to know the hydrometeo-
rological conditions like type of drought in the study area
by using the rainfall ratio mentioned by Bhargava [1].
3. Results
Hydrometeorological Elements
Hydrometeorology is the science that deals with the ap-
plication of meteorology to water problem. Hydrome-
teorlogical conditions mainly deal with the climatologi-
cally conditions, which affect groundwater of an area.
Climate: The area is a part of the chronically drought-
affected district (Anantapur) of Andhra Pradesh and fal-
ling in the rain-shadow region of Peninsular India. The
study area receives erratic and scanty rainfall. This area
experiences hot summers and mild winters. During De-
cember-January the temperature is the lowest touching
20˚C and during April-May the temperature shoots up to
42˚C. Humidity varies from 75 to 85 percent in rainy
season and is almost dry (20% to 25%) during the period
May and June. Wind speeds are generally light to mo-
derate, but become stronger during the southwest mon-
soon period. During this period the average wind velocity
varies from 18 km/h to 28 km/h, whereas it lowers to 8 to
C
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K. S. S. PRASAD ET AL. 295
Figure 1. Location map of the area investigated.
12 km/h during October and November (northeast mon-
soon period).
Precipitation: Rainfall data are collected for four
rainguage stations in and around the study area from the
meteorological department of Anantapur. The minimum,
maximum and mean rainfall data is presented for the
four-rainguage stations in Table 1. The monthly and an-
nual rainfall data of Kadiri rainguage station from 1990
to 2003 is given in the Table 2. The annual rainfall at
Kadiri station ranges from 2037 mm (in 1998) to 394
mm (in 2002) with a mean value of 785 mm. From the
Figure 2 it is observed that the rainfall is deviated posi-
tively the years 1996, 1998 and 2002, but it shows nega-
tive deviation in the rest of the eleven years. The mini-
mum rainfall in the month of January and maximum in
the months of August to October are noticed (Table 2).
The southwest monsoon during June to August contri-
butes to 62% of the rainfall. The northeast monsoon,
which breaks in the month of September, brings 27%
of rainfall until December (Table 3). The heavy rain-
fall is due to the cyclone depressions and storms caused
in the Bay of Bengal during the period of northeast
monsoon.
Rainfall Ratio: According to Bhargava [1] the rainfall
ratio is defined as the abnormalities in the occurrence of
rainfall at any location. It can be obtained from the for-
mula given below:
Rainfall Ratio = xmx
n
PP 100
P
where Px = Maximum yearly rainfall;
Pm = Minimum yearly rainfall;
Pn = Average yearly rainfall.
The high rainfall ratio indicates high abnormalities,
hereas low ratio indicates greater stability of rainfall. w
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K. S. S. PRASAD ET AL.
296
Table 1. Annual rainfall data in and around the study area for 14 years (1990-2003).
S. No Year Kadiri (in mm) O. D. Cheruvu (in mm)Gandlapenta (in mm) Nallacheruvu (in mm)
1 1990 596.4 513.8 690.5 437.7
2 1991 559.6 875.2 886.6 703.2
3 1992 438.4 552.8 501.6 521.2
4 1993 527.4 464.0 596.8 567.3
5 1994 466.0 537.0 352.8 463.2
6 1995 738.4 695.0 589.8 565.8
7 1996 1243.0 1221.4 1050.6 770.0
8 1997 664.6 618.0 576.0 555.6
9 1998 2037.6 519.0 714.6 718.2
10 1999 436.6 352.0 405.8 308.4
11 2000 991.4 604.8 721.2 395.8
12 2001 589.4 601.6 896.0 790.9
13 2002 394.4 504.8 282.8 378.2
14 2003 573.0 330.6 605.0 529.6
Maximum 2037.6 1221.4 1050.6 790.9
Minimum 394.4 338.6 282.8 308.4
Mean 785.3 599.3 605.0 550.4
Table 2. Monthly rainfall data of kadiri rain-gauge station (in mm).
Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Ann. Rain fall
1990 0.0 0.0 39.2 0.0 117.8 57.8 27.6 92.2 95.6 67.6 98.6 0.0 596.4
1991 0.0 0.0 0.0 23.0 54.2 103.2 31.8 69.8 2.2 261.0 113.4 0.0 559.6
1992 0.0 0.0 0.0 0.0 30.2 35.8 37.2 99.2 60.0 63.0 113.0 0.0 438.4
1993 0.0 0.0 6.2 0.0 15.6 45.2 93.4 67.0 72.0 132.8 40.8 54.4 527.4
1994 0.0 0.0 0.0 7.0 114.0 41.6 61.8 18.2 7.0 162.6 46.8 7.0 466.0
1995 4.8 0.0 23.4 0.0 53.8 57.6 214.6 117.0 178.6 88.6 0.0 0.0 738.4
1996 0.0 0.0 0.0 100.6 22.0 270.8 74.4 145.2 288.8 311.2 16.0 14.0 1243.0
1997 0.0 0.0 64.6 37.2 0.0 108.0 2.4 130.8 163.6 66.4 64.2 27.4 664.6
1998 0.0 0.0 0.0 9.0 47.2 66.2 160.6 1644.0 110.6 0.0 0.0 0.0 2037.6
1999 0.0 0.0 0.0 0.0 0.0 57.2 64.6 66.0 101.4 89.4 52.0 6.0 436.6
2000 0.0 50.0 0.0 0.0 159.2 82.4 105.0 292.2 133.2 151.6 5.6 12.4 991.4
2001 0.0 0.0 4.6 99.4 18.8 44.2 29.6 91.2 164.8 355.2 45.6 5.0 589.4
2002 0.0 0.0 0.0 48.4 46.2 24.8 19.6 25.0 94.0 116.0 17.2 3.2 394.4
2003 0.0 0.0 0.0 8.2 0.0 62.8 103.0 74.6 58.0 251.2 2.2 0.0 573.0
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K. S. S. PRASAD ET AL. 297
Figure 2. The deviation of the rainfall from the mean an-
nual rainfall.
Table 3. Percentage precipitation in the study area (in mm).
S. No Period Percentage of
precipitation
1 South-West Monsoon
(Jun, Jul, Aug and Sept.) 61.6%
2 North-East Monsoon
(Oct, Nov and Dec.) 26.9%
3 Torential (Hot) Weather
(Feb to May) 10.9%
The rainfall ratio of the study area shows very high va-
lues (i.e., 180 to 962) denoting that there is much variation
in annual rainfall from the normal rain of year (Tab le 5 ).
It confirms the erratic nature of rainfall in the study area.
4. Discussion
4.1. Identification of Drought Types
The Indian Meteorological Department (IMD) has taken
deviation from the mean annual rainfall for describing
the drought intensity. It is considered that if the deviation
from the mean lies between 10% and 20%—Slightly
Drought 20% and 30%—Moderate Drought 30% and
40%—Severe Drought and above 40%—Disastrous.
From the Table 4 it is observed that in the 14 years
period only three years (1966, 1998 and 2000) are posi-
tive and rest of the 11 years are drought-prone with
varying intensities. Out of the 11, 4 years (1992, 1994,
Table 4. Rainfall deviation and rainfall ratio for the study
area.
Year Deviation % of Deviation Rainfall Ratio
1990 –186.9 24 180
1991 –225.7 29 470
1992 –346.9 44 230
1993 –257.9 33 290
1994 –319.3 41 400
1995 –46.9 06 340
1996 +457.7 - 290
1997 –120.7 15 290
1998 +1252.3 - 962
1999 –348.7 44 262
2000 +206.1 - 346
2001 –195.9 25 496
2002 –390.9 50 343
2003 –212.3 27 522
1999 and 2002) experienced disastrous type of drought
with more than 40% of deviation from the mean annual
rainfall. Only the year 1993 comes under severe type
with 33% and the rest of the six years have experienced
moderate to slightly drought conditions.
4.2. Water Table Characteristics
The movement of groundwater in the weathered and
fractured rocks is dependent on the degree of inter-con-
necting interstices, topography, and conditions of rechar-
ge and discharge. The thickness of the zone of saturation
is also dependent on the said factors. The zone of satura-
tion generally follows the configuration of the topogra-
phy of the area. In general, the water level starts to rise
from the month of July, and continues up to December
depending on the amount of precipitation, while it starts
to decline from the month of January and continues up to
the end of June.
An inventory of 41 wells in the study area enables us
to understand the hydrodynamic characteristics of the
study area. The depth to water table is recorded for all
the wells. The altitude of the wells is determined by us-
ing GPS. While collecting the data, sufficient care is ta-
ken to avoid perched aquifers. The water table levels are
recorded during the pre-monsoon (June, 2002) season
and post-monsoon (January, 2003) seasons (Table 5). Wa-
ter table maps of the area with respect to the mean sea
level (MSL) are prepared for both pre- and post-monsoon
seasons (Figures 3 and 4).
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K. S. S. PRASAD ET AL.
298
Table 5. Water table fluctuations of the study area (in m).
S.No Location Well Depth (m)
Water table in Pre-Monsoon
(above MSL)
Water table in Post-monsoon
(above MSL)
Difference in
Watertable (in m)
1 Allipur Tanda-1 8 499.6 503.8 4.2
2 Gollavari Palle 6 513.2 515.8 2.6
3 Mutyalacharuvu 9 500.2 503.6 3.4
4 Battalapalle-1 6 496.2 500.8 4.6
5 Battalapalle-2 10 503.2 506.0 2.8
6 Eguvapalle 8 577.0 580.6 3.6
7 Mallayyagaripalle 11 546.9 551.0 4.1
8 Kareddipalle 8 514.5 517.8 3.3
9 Tellaguntapalle 11 555.0 558.8 3.8
10 Tavalamarri 10 553.2 557.4 4.2
11 Mustipalle 12 594.4 598.2 3.8
12 Tummalabayulu 7 604.4 608.8 4.4
13 Gangannagaripalle 8 506.6 509.8 3.2
14 Chittivaripalle 6 556.2 560.8 4.6
15 Burugapalle 9 572.4 577.6 5.2
16 Pulikuntapalle 10 611.4 617.2 5.8
17 Tirumalavaripalle 9 514.2 517.4 3.2
18 Sivarampalle 11 521.8 524.9 3.1
19 Pantulacharuvu 8 526.9 529.7 2.8
20 Boyaramayyapalle 10 554.3 558.9 4.6
21 Erradoddi Tanda 12 477.2 482.4 5.2
22 Kummaravaripalle 11 487.8 492.6 4.8
23 Barigareddipalle 8 509.1 513.2 4.1
24 Nillavaripalle 9 554.8 557.8 3.0
25 Allipur Tanda-2 7 475.2 478.0 2.8
26 Devaracharuvu Lands 6 457.5 460.4 2.9
27 Metukupalle 9 550.7 553.2 2.5
28 Nagireddipalle 11 521.0 524.7 3.7
29 Beripalle Lands 12 488.7 492.6 3.9
30 Sidapuram 8 502.7 505.9 3.2
31 Kuttagulla 11 482.4 486.7 4.3
32 Errakuntapalle 19 503.4 509.2 5.8
33 Kadiri 10 474.1 478.9 4.8
34 Kavulapalle 8 503.6 507.2 3.6
35 Jagannapeta 16 521.6 527.8 6.2
36 Kottapalle 14 531.7 536.1 4.4
37 Payalavandapalle 18 571.4 575.2 3.8
38 Allugunda 8 553.0 557.2 4.2
39 Nallacheruvu RS 14 544.8 550.4 5.6
40 Rangannagari Palle 12 564.3 568.9 4.6
41 Deverintipalle 10 560.8 564.8 3.8
Min 6 474.1 478.0 2.6
Max 19 611.4 617.2 6.2
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K. S. S. PRASAD ET AL. 299
Figure 3. Water table fluctuation map (pre-monsoon) of the study area.
Figure 4. Water table fluctuation map (post-monsoon) of the study area.
Water level variations in the study area depend on the
amount of precipitation, influent and effluent nature of
the streams, geology of the area, slope of the area and
infiltration capacity of the soils. The seasonal variations
in the ground water also correlate with the data of the
rainfall. The water level has shown a rise during Novem-
ber-December months due to the rainfall percolation du-
ring October to December months. This clearly reveals
that there is a net recharge of groundwater due to the
influence of rainfall only. The water level starts to de-
cline from the month of February and reaches maximum
in the month of June. This is mainly due to the depletion
of rainfall and groundwater withdrawals for irrigation.
The fluctuations in the water table level have direct
relationship with rainfall in the study area. The factors
like intensity of rainfall and its variation with time and
place, temperature, surface and sub-surface soil charac-
teristics and vegetation cover play an important role in
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K. S. S. PRASAD ET AL.
300
Figure 5. Hydrograph of the Kadiri area.
the water level fluctuations besides topography.
4.3. Hydrograph
The monthly water table levels in observation wells of
Kadiri and its surroundings for a period of four years
(2000 to 2003) correlate with the monthly values of rain-
fall data (Figure 5). From the observation of the hydro-
graph, it is noticed that the rise of water level starts im-
mediately after the soil moisture reaches its maximum
water-holding capacity. The water table level rises to a
maximum in the months of November and December.
The groundwater levels show seasonal fluctuations in-
fluenced by rainfall and pumping of water from the wells
for irrigation. In general, water level gradually increases
during post-monsoon period (i.e., from June to December)
and decreases during pre-monsoon period (i.e., January
to June). Changes in climate also produce water level
fluctuations in the wells. During post-monsoon period,
the climate is cool and evaporation less while during pre-
onsoon season, the climate is hot and evaporation more. m
5. Conclusion
Hydrometeorological studies reveal that the study area
comes under semi-arid zone. The rainfall data for 14
years (1900 to 2003) of the study area reveal that only
three years (1996, 1998 and 2003) had sufficient rainfall
and rest of the 11 years are drought-prone to varying in-
tensities. It is also observed that the water table gradually
increases during the June to December (post-monsoon)
and decreases during January to June (pre-monsoon). The
fluctuations in water table vary from 2.6 m to 6.2 m with
a mean value of 4.01 m. The area receives maximum
amount of rainfall from south-west monsoon.
REFERENCES
[1] P. N. Bhargava, “Statistical Studies on the Behaviour of
Rainfall in a Region in Relation to a Crop,” Indian Agri-
cultural Research Station and Indian Council of Agricul-
tural Research, New Delhi, 1977.
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