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The present study evaluates the temporal variation of aerosol optical depth (AOD(500nm)) and the Angstrom parameters [viz., Angstrom exponent (AE, alpha), Angstrom turbidity coefficient (beta) and second order Angstrom exponent (alpha’)] at a tropical observing site, Pune (18 degrees 32’ N; 73 degrees 49’ E, 559 m AMSL) during 2008-15. Six-year means for winter and premonsoon seasons together are found to be 0.534 +/- 0.13, 1.054 +/- 0.27, 0.254 +/- 0.08 and 0.167 +/- 1.33 for AOD(500 nm), AE, beta and a’ respectively. Average month-to-month variability of AOD500 nm, AE, beta and a’ during 2008-15 depicts seasonal cycle with strong departures with respect to long-term means. Frequency distributions for AOD, AE and beta are positively skewed (skewness = 0.77, 0.32 and 1.14 respectively) while it is negatively skewed for alpha’ (skewness = -0.18). Analysis of AE difference, curvature parameter difference (alpha(2)-alpha(1)) and AOD(500 nm)-AE(440-870 nm) contour density map reveals that the aerosol ensemble at Pune consists of four aerosol types viz., UI (urban/industrial), CM (clear maritime), DD (desert dust) and MT (mixed type). Their relative magnitudes, however, differ during winter and pre-monsoon seasons. Thus, the contour density map shows dominance of UI and relatively less occurrence of MT type aerosols during winter. In pre-monsoon, however, the aerosol scenario is driven by MT type aerosol although UI and DD type aerosols show their remarkable existence.