Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6339973 | Atmospheric Environment | 2014 | 10 Pages |
Abstract
While the formation of new atmospheric aerosol particles and their subsequent growth have been observed under diverse environmental conditions globally, such observations are very scarce over Indian subcontinent. Here, we present the systematic analysis for new particle formation (NPF) from two distinct urban locations in India during April-May of two consecutive years. Particle size distributions were measured at Pune (18.53°N, 73.85°E) during 16 April-23 May, 2012 and at Kanpur (26.46°N, 80.32°E) during 16 April-23 May, 2013. The campaign mean total particle number concentration in the similar size range of 4-135 nm at Pune (12.2 Ã 103 cmâ3) was higher than at Kanpur (7.9 Ã 103 cmâ3), whereas the estimated total condensation sink (CS4-750) at Pune (16.2 Ã 10â3 sâ1) was lower than at Kanpur (33.3 Ã 10â3 sâ1). Despite lower particle number concentrations at Kanpur, larger particle sizes resulted in higher condensation sink than at Pune. The mean particle mode diameter at Kanpur was found larger by a factor of â¼1.8 than at Pune. NPF events were observed commonly at both sites, with lower frequency at Kanpur (14%) than that at Pune (26%). The derived particle growth rates, GR, and the formation rates of 5 nm particles, J5, ranged from 3.4 to 13.3 nm hâ1 and 0.4 to 13.9 cmâ3 sâ1, respectively, which are generally comparable to typical values reported in previous studies. Generally, the particle growth rates were found higher at Kanpur, whereas the formation rates were higher at Pune. It appears that the presence of pre-existing large particles at Kanpur than at Pune suppressed formation rates and favored particle growth. Overall, NPF occurred at lower condensation sink, lower RH, higher solar radiation, and higher temperature.
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Atmospheric Science
Authors
V.P. Kanawade, Sachchida N. Tripathi, Devendraa Siingh, Alok S. Gautam, Atul K. Srivastava, Adarsh K. Kamra, Vijay K. Soni, Virendra Sethi,