Abstract—The climatic condition over Indian region is highly dependent on monsoon. India receives maximum amount of rainfall during southwest monsoon. Indian economy is highly dependent on agriculture. The presence of flood and drought years influenced the total cultivation system as well as the economy of the country as Indian agricultural systems is still highly dependent on the monsoon rainfall. The present study has been planned to investigate the flood and drought years for the north-west Himalayan region from 1951 to 2014 by using area average Indian Meteorological Department (IMD) rainfall data. For this investigation the Normalized index (NI) has been utilized to find out whether the particular year is drought or flood. The data have been extracted for the north-west Himalayan (NWH) region states namely Uttarakhand (UK), Himachal Pradesh (HP) and Jammu and Kashmir (J&K) to find out the rainy season average rainfall for each year, climatological mean and the standard deviation. After calculation it has been plotted by the diagrams (or graphs) to show the results- some of the years associated with drought years, some are flood years and rest are neutral. The flood and drought years can also relate with the large-scale phenomena El- Nino and La-Lina. Keywords—Indian Meteorological Department, Rainfall, Normalized index, Flood, Drought, NWH. I. INTRODUCTION S the Himalayas is huge source of water in the form of both liquid (carried by different drainage system) and solid (snowfall and ice on the mountain), it is called ‘Water Tower of Asia’ [1]. It also plays an important role in air circulation too which influences the climatic condition in the Indian region by defending rain-bearing south-westerly monsoon to give up maximum precipitation over Indian region in rainy season [2]. The extreme weather events like flash floods, heavy precipitation, cloud burst, and landslides have become regular in the western Himalayan region [3]. The climatic condition of the NWH region is controlled by the south-west monsoon from June to September (JJAS) and westerly disturbance from November to March. But there is a detectable change observed in monsoon precipitation only [4]. In that region severe effect on water availability has been created due to the overall changing pattern of rainfall which also leads to water stress as well as drought [5]. Recent study Sudip K. Kundu, former M. Tech student was with the Indian Institute of remote Sensing, Dehradun, UK-248001, India (phone: +91 9883233977; e- mail: sudipkrkundugeoh@gmail.com). Charu Singh is associated as a scientist with the Indian Institute of remote Sensing, ISRO, Dehradun, UK-248001, India (phone: +91 135 2524183; e- mail: charu@iirs.gov.in). indicates that the rainfall becomes more intense in such a way that more precipitation takes place over a short time period. As a result, higher intensity and incidence of floods, especially flash flood happens in the river basins. On the other hand, it increases the runoff which reduces the amount of groundwater recharge. There is also a significant relationship between agricultural production and climate variabilities such as floods and droughts [6]. In that context, the present study has been planned to compute the flood and drought years using IMD rainfall data over NWH region to understand the relationship of extreme weather events like floods and droughts with the changing rainfall pattern. II. STUDY AREA The study area is North-West Himalayan region (Fig. 1). It encompasses three states namely Jammu & Kashmir, Himachal Pradesh and Uttarakhand. The geographical extension of this region varies in between 28° to 37° North latitudes and 72° to 82° East longitudes. Fig. 1 Study area map of NWH region III. DATASETS AND METHODOLOGY The area average IMD rainfall data have been utilized for June, July, August, September (JJAS) during 1951 to 2014. The month wise rainfall data of JJAS have been converted into total monsoon season rainfall during 1951 to 2014. We have used the NI method to find out the flood and drought years. The NI can be defined as follows: Computation of Flood and Drought Years over the North-West Himalayan Region Using Indian Meteorological Department Rainfall Data Sudip Kumar Kundu, Charu Singh A World Academy of Science, Engineering and Technology International Journal of Geological and Environmental Engineering Vol:13, No:7, 2019 491 International Scholarly and Scientific Research & Innovation 13(7) 2019 ISNI:0000000091950263 Open Science Index, Geological and Environmental Engineering Vol:13, No:7, 2019 waset.org/Publication/10010550