Raindrop size distribution variations in <i>JAL</i> and <i>NILAM</i> cyclones induced precipitation observed over Kadapa (14.47^oN, 78.82^oE), a tropical semi-arid region of India

Abstract

Raindrop size distributions (RSD) of <i>JAL</i> (7 November 2010) and <i>NILAM</i> (29 October 2012) cyclones induced precipitation were measured with PARticle SIze and VELocity (PARSIVEL) disdrometer deployed at Kadapa (14.47°N, 78.82°E), a semi-arid continental site in Andhra Pradesh. Small and mid drops below 2 mm diameter have higher concentration in <i>JAL</i> and <i>NILAM</i> cyclones. RSD characteristics stratified on the basis of rainrate showed that the concentration of small (large) drops is higher (lesser) for <i>JAL</i> cyclone than <i>NILAM</i> cyclone. The concentration of mid size drops of <i>JAL</i> cyclone are greater than or equal to that of <i>NILAM</i> cyclone. The <i>JAL</i> cyclone induced precipitation is associated with higher (lesser) concentration of small drops (small and mid drops) in stratiform (convective) region than that of <i>NILAM</i> cyclone precipitation. <i>JAL</i> cyclone has long duration of stratiform rainfall with smaller raindrop compared to <i>NILAM</i> cyclone, which had a short duration of stratiform rainfall with more number of mid and large drops. In both convective and stratiform regimes, the coefficient value of Z-R relations is higher in <i>NILAM</i> cyclone than <i>JAL</i> cyclone. The average mass weighted diameter, D_m of <i>JAL</i> cyclone is smaller (larger) in stratiform (convective) than that of <i>NILAM</i> precipitation.