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Agricultural Drought Indices - US Department of Agriculture

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Further, a year is considered a “drought year” when the area affected by moderate and severe<br />

drought either individually or together is 20-40% <strong>of</strong> the total area <strong>of</strong> the country and seasonal<br />

rainfall deficiency during the southwest monsoon season for the country as a whole is at least 10%<br />

or more. When the spatial coverage <strong>of</strong> drought is more than 40% then it is called an all-India<br />

severe drought year (www.imd.gov.in).<br />

Based on the index <strong>of</strong> percentage departure <strong>of</strong> rainfall from normal, IMD has delineated drought by<br />

subdivision since 1875. The droughts over a period <strong>of</strong> 135 years (1875-2009) have been identified<br />

and classified so far. Further, the drought-prone areas have been identified and probabilities <strong>of</strong><br />

moderate and severe drought occurrences have also been computed by subdivision over the<br />

country (Table 1).<br />

Table 1. Subdivision frequencies <strong>of</strong> moderate and severe drought during 1875-2009 and probabilities<br />

<strong>of</strong> drought years.<br />

Sl.No. Name <strong>of</strong> subdivision Moderate Severe Total <strong>Drought</strong><br />

probabilities<br />

(Total) %<br />

1. Andaman & Nicobar Islands 17 0 17 13<br />

2. Arunachal Pradsh 7 1 8 6<br />

3. Assam & Meghalaya 5 0 5 4<br />

4. Nagaland, Manipur, Mizoram & Tripura 12 0 12 9<br />

5. Sub-Himalayan West Bengal 7 0 7 5<br />

6. Gangetic West Bengal 2 0 2 1<br />

7. Orissa 5 0 5 4<br />

8. Bihar 12 0 12 9<br />

9. Jharkhand 6 0 6 4<br />

10. East Uttar Pradesh 13 1 14 10<br />

11. West Uttar Pradesh 13 1 14 10<br />

12. Uttarakhand 16 2 18 13<br />

13. Haryana, Delhi & Chandigarh 21 4 25 19<br />

14. Punjab 20 4 24 18<br />

15. Himachal Pradesh 20 3 23 17<br />

16. Jammu & Kashmir 21 6 27 20<br />

17. West Rajasthan 22 12 34 25<br />

18. East Rajasthan 18 5 23 17<br />

19. West Madhya Pradesh 14 0 14 10<br />

20 East Madhya Pradesh (including<br />

12 0 12 9<br />

Chhattisgarh)<br />

21. Gujarat Region 17 11 28 21<br />

22. Saurashtra & Kutch 16 15 31 23<br />

23. Konkan & Goa 9 0 9 7<br />

24. Madhya Maharashtra 7 2 9 7<br />

25. Marathwada 17 1 18 13<br />

26. Vidarbha 16 1 17 13<br />

27. Coastal Andhra Pradesh 13 0 13 10<br />

28. Telangana 18 0 18 13<br />

29. Rayalaseema 20 2 22 16<br />

30. Tamil Nadu & Pondicherry 12 0 12 9<br />

31. Coastal Karnataka 5 0 5 4<br />

32. North Interior Karnataka 10 0 10 7<br />

33. South Interior Karnataka 9 0 9 7<br />

34. Kerala 10 0 10 7<br />

35. Lakshdweep 10 3 13 10<br />

Data in Table 1 reveal that the arid west, namely West Rajasthan (34 cases) and Saurashtra and<br />

Kutch (31 cases), have the highest occurrences <strong>of</strong> drought. The adjoining Gujarat region, which<br />

mostly belongs to a semiarid climate, also experiences high incidences <strong>of</strong> drought (28). Other<br />

51

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