Effect of Climate Change on Rainfall Pattern and Socio-economic Condition for Karnataka State

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1 Effect of Climate Change on Rainfall Pattern and Socio-economic Condition for Karnataka State ABSTRACT Mallappa J. Madolli 1, Sumit Sen 2 and Aditya R. Shinde 3 1,2,3Department of Hydrology, Indian Institute of Technology, Roorkee mallappa495@gmail.com, 2sensumit2@gmail.com, 3 agrocker72@gmail.com Climate change is the changes in the distribution of weather patterns significantly over periods ranging from decades to millions of years. This will lead to occurrence of extreme events such as floods and drought. In the state of Karnataka, India there is a huge impact of climate change on rainfall patterns as well as socio-economic condition of the people. Specific objective of the study is to show the impact of climate change on fluctuation of rainfall pattern and socio-economic condition for the study area. In this study SPI index is used to show the changes in rainfall patterns, which values are varies from +3 to -3 this indicates huge variation of rainfall patterns in the study area during the last decade. Rainfall analysis for the period of 1901 to 2012 showed both decrease (0 to -60%) and increase (0 to +24%) in rainfall from the normal rainfall in the study area due to climate variability and global climate change. Furthermore drought analysis results showed that drought intensity in Karnataka state which used to once in four years, however, due to climate change and climate variability, districts under dry zone are subjected to continuous drought during the last decade. In addition, impacts of climate change and variability was seen in agricultural sector. The agricultural income of households has reduced to half in as compared to 2005 to Keywords: Climate change, Drought, SPI, Rainfall pattern INTRODUCTION Climate change is the changes in the distribution of weather patterns over periods ranging from decades to millions of years. Factors which are cause for global climate change are enhanced greenhouse gas emissions, variation in net solar radiation received, changes in land use and land cover pattern, biotic process, plate tectonics and volcanic eruption (Arnel, 2004, Prasad, 2006, Pandey et al., 2008, Shivakumar, 2010, Yogesh, 2013). IPCC (2001; 2007) suggested various indicators of global climate change. For example, sea level is rising at a rate of 3.16 mm per year, land ice is melting at 100 billion tons per year, arctic ice glaciers is decreasing at 11.5% per decade, global surface temperature increase of 0.42 to C per century and an increase in sea surface temperature anomaly are some of the indicators of global climate change. Past study (IPCC, 2001, Sharma & Singh, 2007, Huang, 2010, Yang, 2011) has shown that global climate change has significant impact on water resources all over the world. It has been estimated that globally occurrence of precipitation is increased about 10 to 15% but at regional scale both decrease and increase were projected (IPCC, 2007). These fluctuations in weather

2 Effect of Climate Change on Rainfall Pattern and Socio-economic 305 pattern can lead to occurrence of hydro-meteorological extreme events floods and drought all over the world. In recent decades it has been found that frequency and magnitude of hydro-meteorological extreme events is increased significantly due to change in fluctuation of rainfall patterns and its distribution (IPCC, 2001, Sharma & Singh, 2007). Indian subcontinent is the most vulnerable to hydro-meteorological extreme events because of its wide variety of agro climatic zones and topography (Pandey, 2008). In the world India is one of the most natural disaster prone country about one sixth (55 m-ha) geographical area is drought prone and one eighth (40 m-ha) of geographical area is flood prone (Sharma & Singh, 2007). From 1801 to 2012 there were 41 drought years have occurred in India. Among these drought years six were the severe drought and twenty three were major drought years (Surinder, 2011; MDM, 2009). Many of among these droughts turned into famines which lead to food insecurity, vulnerable to infectious disease, inadequate food for cattle these leads huge impact on socioeconomic condition for region meanwhile to country (MDM, 2009). Flood is one of the other major climate change impact which cause structural damage over region, such as damage houses, industries, public utilities and property resulting in huge economic losses, apart from loss of lives. In India from 1953 to 1999 due to flood, a total damage caused for Rs billion, affecting a 8.11 m-ha geographical area, a lost of 1579 humans lives and number cattle (NIH, 2008). A recent flash flood disaster occurred on 16 th to 17 th June, 2013 in the state of Uttarakhand caused more than 2000 lives and around cattle were lost. Indian most of the economy depends upon agriculture but agriculture sector depend upon the south west monsoon precipitation. South west monsoon is so complex phenomenon because complexity in numerous atmospheric and land cover parameters (Bhuiyan, 2006). In recent decades due to global climate change and change in land cover south west monsoon is so erratic in nature and change in distribution of precipitation such that it is difficult to predict its onset, movement and distribution throughout the country. For same reason occurrence of precipitation over country is increased but both increase and decrease were projected at regional scale Sharma & Singh, 2007). These leads to huge impact on agriculture sector in terms of cropping pattern, reduction in production and yield. This directly impact not only for food insecurity but also for poverty and inequality concern for nation (Prabhat & Koji, 2012). Since the Karnataka is an agricultural-based state of India, rainfall plays an important role for fulfillment of water requirement in terms of agricultural as well as domestic purposes. So any change in rainfall from normal mean rainfall will have a significantly impact on socio-economic condition of the area (Ravindranat, Brahmam, & Vijayaraghavan, 2005, Prabhat, & Koji, 2012). Recently it has been suggested by citizens of Karnataka state that there is huge impact of climate variability and global climate change on rainfall pattern.

3 306 Green India: Strategic Knowledge for Combating Climate Change: Prospects & Challenges Krishnegouda (2011) studied the Rainfall analysis of Bhadra command area (Karnataka) for three major districts Shimoga, Davangere and Chikamagalore and found that rainfall in the region is showing a constantly rising trend mainly due to climate change and human intervention. However, there is still a gap of information to understand the rainfall fluctuation at a district-and state-level and how it relates to the agricultural productivity of the state. Therefore, the specific objectives of the study are to find out the changes in rainfall patterns by developing the Standard Precipitation Index at the district-level, and to understand the relationship between the change in rainfall patterns and agricultural sector. MATERIAL AND METHODS Study area: Karnataka is located on the western coast of peninsular India, enclosed in between N to N and 74 0 E to E. Geographical area of Karnataka about square kilometers, comprising of 30 districts (Figure 1). Karnataka geographical zones broadly categorized into three types; Coastal region, Western Ghats region and Deccan plateau. Indian meteorological department broadly categorized Karnataka geographical zones into three zones; coastal, north interior and south interior among these, coastal zone receives highest annual rainfall (average 3638 mm) and north interior zone receives less rainfall, the state average annual rainfall is 1139 mm. The highest and lowest temperature recorded in the state was 45.6 o C and 2.8 o C at Raichur and Bidar, respectively. Fig. 1: District-Wise Map of Karnataka

4 Effect of Climate Change on Rainfall Pattern and Socio-economic 307 Data used: Two types of data were used for current study, meteorological data and agricultural statistics. For meteorological data, district-wise monthly precipitation data for period of 1901 to 2012 were collected from Indian water Portal site ( and agricultural statistics were collected from Department of Agriculture, Karnataka state, India. STANDARD PRECIPITATION INDEX Standard precipitation index (SPI) is a probability based index, developed to better representation of abnormal wetness and dryness (Mckee, 1993). In the present study, SPI is used for measuring drought severity as well as for analyzing fluctuation of rainfall pattern. It has been found that in India SPI is the best tool to monitor meteorological drought (Jayantasarkar, 2010, Pai, 2011). Because 60 to 70% of Indian economy depend upon agriculture and these agriculture purely depend upon south west monsoon rainfall. Therefore by using single parameter rainfall to monitor and analysis of drought SPI gives better results than the other indices such as percent of normal (PN), Palmer drought severity index (PDSI), Surface water supply index (SWSI) etc. SPI is simply calculated by taking the difference of the precipitation from the mean for a particular time step and then dividing it by the standard deviation. SPI = Where X i is the actual precipitation, X avg is the mean precipitation and σ is the standard deviation. For current study, 27 district SPI values were developed with time steps of 1, 3, 6 and 12 months by using the inverse distance squared weighting procedure of the Spatial and Time Series Information Modeling software package (SPATSIM, Institute for Water Research (IWR), Rhodes University, South Africa). Mckee (1993) SPI values ranges both above and below zero, > + 2 & <-2 being extremely wet and dry respectively, to & to-1.50 being severe wet and dry respectively, to +1.0 & to -1.0 being moderately wet and dry respectively and values-0.99 to are near normal. The twelve month SPI maps were used to show annual fluctuation of rainfall from its mean than 1, 3 and 6 month SPI maps. Therefore in the present study 12 month district-wise SPI maps were developed for better understanding of rainfall pattern fluctuations. RESULTS AND DISCUSSIONS DISTRICT-WISE SPI ANALYSIS Monthly district-wise SPI maps were developed over the period of 1950 to Analysis showed that changing trend in rainfall pattern. Results in Table 1 showed that there is an increase in rainfall amount in some districts, however, for the same time period other districts showed a decrease in rainfall. More specifically, rainfall in districts under Western Ghats and Coastal regions of Karnataka received 3 to 25% increase in mean rainfall during last decade and the SPI values of these regions are more than 0 for most of years. This (1)

5 308 Green India: Strategic Knowledge for Combating Climate Change: Prospects & Challenges means that during last decade more wet years occurred in these districts. However, most of the districts under southern and northern interior zones showed a rainfall deficit of about 1 to 60% from mean rainfall except Raichur, Gulbarga, Bidar, Bangalore urban and Bangalore rural districts. By definition, if an area has rainfall deficiency of more than 10% that area is under meteorological drought,and if rainfall deficiency is up to 60%, it means that during last decade a continuous severe drought has occurred. In these districts there is huge impact on socio-economic communities, water dependent sectors and environment. In Raichur, Gulbarga, Bidar, Bangalore urban and Bangalore rural districts rainfall was increased about 3 to 10% from mean rainfall. A detailed analysis for four districts under all three regions, such as Dharwad district of north interior west dry zone, Raichur under north interior east dry zone, Kodagu district under Western Ghat and Banglore urban district under south interior dry zone were considered. Fig. 2 5 shows the twelve month SPI map for Dharwad, Raichur, Kodagu and Bangalore urban districts. Sl. No. Name of District Table 1: District-Wise Rainfall Analysis and SPI Value Range Annual Mean Rainfall for the Period of 1901 to 2012 Annual Mean Rainfall for the Period of 2001 to 2012 Rainfall Deficiency from Mean SPI Values For the Period of Bagalakote to Bangalore Rural to Bangalore to Belgaum to Bellary to Bidar to Bijapur to Chamarajanagar to Chikmagalur to chitradurga to D. Kannada NA 12 Davanagere to Dharwad to Gadag to Gulbarga to Hassan to Haveri to Kodagu to Kolar to Koppal to Mandya to Mysore to Raichur to Shimoga to Tumkur to U.kannada NA 27 Udupi NA Note: NA not Analyze

6 Effect of Climate Change on Rainfall Pattern and Socio-economic 309 For the Dharwad district, it was clearly found that before 2001, only 9 dry years occurred with min SPI values ranging from to -0.65, which could be considered as near normal (Mckee 1993). However, for the whole period from 2001 to 2012 SPI values were-0.38 to suggesting that there was a continuous moderate to severe drought in the district. For same time period ( ), the Kodagu district showed an opposite trend as compared to Dharwad. SPI values ranges from-0.68 to 3.08 suggesting that there is normal to very wet years occurred in the Kodagu. However, for Bangalore urban and Raichur Districts during 2001 and 2012 rainfall was increased about 10% because of increasing number of wet years in the last decade. Overall, this analysis showed that both increase and decrease in rainfall amount as well as there is a changing trend in the number of wet and dry years occurring in the study area. Fig. 2-5: Twelve Month SPI Map for Dharwad, Raichur, Kodagu & Bangalore Urban District Overall rainfall pattern fluctuation over the whole study area (i.e., Karnataka State) was studied for the period of 1901 to 2012 using annual average rainfall data (Figs. 6 & 7). Two maps were developed; one is annual mean for the period 1901 to 2012 and second is annual mean for the period of 2000 to By observing the maps it was found that the districts such as Belgaum, Dharwad, Gadag, Haveri, Davangere,Hassan, Mandya, Mysore and Chamarajanagar were shifted moderate rainfall zone ( mm) to low rainfall zone (less than 1400 mm). It leads to continuous drought over period of more than ten years in these districts.

7 310 Green India: Strategic Knowledge for Combating Climate Change: Prospects & Challenges Figs. 6&7: Fluctuation Rainfall Pattern In the current study it was found that there is change in rainfall pattern, but there are several causes for these problems. At regional scale, the possible causes for change in rainfall pattern in the study area are increasing trend in temperature, changes in pattern of wind speed and land use land cover. AGRICULTURE STATISTICAL ANALYSIS From 1998 to 2008 there is huge variation in agricultural land and net sown area due to fluctuation in rainfall pattern in the study area. A decreasing trend in agricultural land was found as shown in Fig. 7. Net area sown fluctuates depending upon water availability in the field. The sown area was found to be the least in Karnataka state from ; it was about 9847 thousand hectares. Overall net sown area is also decreasing from 1998 to Fig. 8&9: Karnataka State Area under Agricultural Land And Net Area Sown Major districts which grow chilli in Karnataka state are in the northern interior and few of them in the southern interior. But during last decade the rainfall in these districts deficiency was more than 25 percent from mean

8 Effect of Climate Change on Rainfall Pattern and Socio-economic 311 rainfall due to which chilli production is decreasing consistently in the study area (Fig. 9). During the same period production in condiments and spices is increasing (Fig. 10) because of net received rainfall has increased in the grown area (Western Ghats region). In the Figs. 7, 8, 9 & 10 it was found that are the worst years in terms of agricultural production. Figs. 10&11: Area Under Chilli, Condiments and Spices In current study for economical analysis, rice and pulses production are used for the period of 2007 to In the figure 11 and 12 it was found that during 2007 to 2013 not a single year achieved the final target in terms of production and economy. Finally in the study it was found that there is huge impact of climate change on agricultural and economic sector of the Karnataka state. CONCLUSION Fig. 11&12: Economical Analysis for Pulses and Rice In the Karnataka state, India there is a huge impact of climate change on rainfall patterns as well as socio-economic condition of the people. In Karnataka state usually the drought intensity was once in four years but due to climate change some of the districts are subjected to continuous drought over a period of more than ten years. In the districts under continuous drought (Dharwad, Mysore, Belgaum, Haveri, Chitradurga, Hassan, Mandya, Gadag and Chamarajanagar) rainfall deficiency is more than 25% from normal during period of 2001 to During the same period north eastern districts such as Bidar, Gulbarga, Raichur, Bangalore rural and Bangalore urban received 3 10% more rainfall than the normal rainfall.in the districts under Western Ghats and coastal region, rainfall has increased from 5 to 25% from normal rainfall. Finally it is concluded that due to impact global climate change fluctuation of rainfall pattern from the normal rainfall, both decrease and increase in rainfall was projected in the study area.

9 312 Green India: Strategic Knowledge for Combating Climate Change: Prospects & Challenges Due to change in rainfall pattern in the state cropping pattern, agricultural production and economy of the state has been significantly affected. Water harvesting, land use planning and alternative crop choice are very effective adaptation measures to resist the heterogeneity observed in rainfall patterns in the study area among all possible strategies. REFERENCES [1] Bhuiyan, C., Singh, R.P., & Kogan, F.N. (2006). Monitoring drought dynamics in the Aravalli region (India) using different indices based on ground and remote sensing data. International Journal of Applied Earth Observation and Geoinformation. [2] Bouba, T.C, Marc C., Mark, T.V.W., Mariana, C.R, & Ken, E.G. (2013). Effects of climate variability and climate change on crop production in Southern Mali.European Journal of Agronomy, 49, [3] Henry, K.N., & Gan, T.Y. (2003).Drought indices and their application to East Africa. International Journal of Climatology, 23, [4] Huang Y. Yang W.F., & Chen, L. (2010).Water resources change in response to climate change in Changjiang river basin. Hydrology and Earth System Sciences and Discussion, 7, [5] IPCC, (April 2002). Technical Paper V, Climate Change and Biodiversity. Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, UK. [6] IPCC, (2007). Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, UK. [7] Jayanta, Sarkar. (2-4 June 2010). Monitoring drought risks in India; with emphasis on agricultural drought. Agricultural Drought Indices Proceedings of an Expert Meeting, Spain. [8] Krishnegouda K., Manjunatha, K. Yadupathyputty R., Manjunatha B.M. (2011). Rainfall analysis of Bhadra command area (Karnataka).Hydrology Journal, 34, [9] Mannava, & Shivakumar, V.K. (2-4 June 2010). Agricultural drought WMO Prospective. Agricultural Drought Indices Proceedings of an Expert Meeting, Spain. [10] Manual for drought management (2009). Department of agricultural and cooperation, Government of India. [11] Mckee T.B., Nolan J.D. & Kleistet J. (17 22 Jan 1993). The relationship of drought frequency and duration to time scales. Eighth Conference on Applied Climatology, California. [12] Nagaraja B.C., Somashekar R.K. & Kavitha A. Impact of Drought on Agriculture: Challenges Facing Poor Farmers of Karnataka, South India. [13] inal%20paper.pdf. [14] National disaster management guidelines, (2010).Government of India. [15] [16] Nigel W.A. (2004). Climate change and global water resources: SRES emissions and socio economic scenarios. Global Environmental Change, 14, [17] Pandey R.P., Dash B.B., Mishra S.K., &Ranvir Singh (2008). Study of indices for drought characterization in KBK districts in Orissa (India).Hydrological Process, 22, [18] Pai D.S., Latha Sridhar., Pulak G., Hatwar H.R. (2011). District-wide drought climatology of the southwest monsoon season over India based on standardized precipitation index (SPI). Natural Hazards, 59, [19] Prabhat B. & Koji K. (2012). Climatic impacts across agricultural crop yield distributions: an application of quintile regression on rice crops in Andhra Pradesh, India. Ecological Economics, 87, [20] Ravindranat M. Brahmam G.N.V., & Vijayaraghavan K. (2005). Effect of drought on nutritional status of rural community in Karnataka. Journal Human Ecology, 18, [21] Sharma K.D. & Pratap Singh (2007). Impact of climate change on hydrological extremes: Floods and droughts. Hydrology Journal, 30, 3 4. [22] Van L.H. A.J., Wanders N., Tallaksen L.M. & Van L.A.F. (2012). Hydrological drought across the world; Impact of climate and physical catchment structure. Hydrology and Earth System Sciences Discussion, 9, [23] XuX., Yang, D. & Sivapalan M. (2011). Assessing the impact of climate variability on catchment water balance and vegetation cover. Hydrology and Earth System Sciences Discussion, 8,