Characteristic feature studies of integrated field intensity of sferics at North-East India

Abstract

Some studies on the variations of integrated field intensity of sferics (IFIS) at 9 kHz are carried out at Mirik (lat 26.9°N, long 88.2°E), a hilly place of North-East India, under different seasonal conditions during January - December 2011. The recorded data are analyzed and interpreted. During locally clear days and nights, IFIS provides a regular behaviour, i.e. field strength remains constant but decreases gradually after the onset of rain. During short period showers, IFIS exhibits a sudden rise and gradual fall. An irregular variation in IFIS is observed with the coverage of roof height cloud mass.