Temporal And Spatial Variability Of Extreme Precipitation And Temperature Over Northeastern Region Of India

Abstract

The Northeastern region (NER) of India is one such region where average annual rainfall newlineis much higher than the all-India average rainfall, and due to its distinctive topographic newlinecharacteristics, this region is susceptible to flooding. The NER of India experienced a newlinelarge number of extreme rainfall events which are responsible for frequent hydrological newlinedisasters like flash floods in the region. Despite this fact, no detail investigation on the newlineextreme events is available for the NER of India. The economy of the NER of India is newlinelargely dependent on the agricultural and forest products and any temporal and spatial newlinevariation in rainfall directly affects the agricultural productivity. This study focused on newlinethe districts located in the states of NER of India excluding the Sikkim state to investigate newlinethe temporal and spatial variations of extreme precipitation and temperature indices. The newlineobjectives of the study are as follows: newline1. To determine the extreme precipitation and temperature indices over districts of North- newlineEastern Region of India, newline2. To investigate temporal trend in the extreme indices of precipitation and temperature, newline3. To correlate extreme precipitation and temperature indices and atmospheric newlinecirculations, and newline4. To generate spatial maps of extreme precipitation and temperature indices, trends and; newlinecorrelation coefficients between extreme precipitation and temperature indices and newlineatmospheric circulations. newlineDaily rainfall data of 0.25°× 0.25° spatial resolution over the period of 1901-2013 and newlinedaily temperature data (Tmax and Tmin) of 1°×1° spatial resolution over the period 1969- newline2005 obtained from a gridded dataset of the India Meteorological Department, Pune were newlineused for the analysis. Two ENSO indices were used in the present study i.e., SOI and newlineNINO3.4. The monthly SOI and NINO3.4 data for period of 1901-2013 were extracted newlinefrom the established record of Climatic Research Unit (CRU) and from the National newlineOceanic and Atmospheric Administration (NOAA) datasets. newline