Title: Estimation of Linke turbidity factors for different regions of India

Authors: Laxmi Narain; S.N. Garg

Addresses: Centre for Energy Studies, Indian Institute of Technology, Hauz Khas, New Delhi – 110016, India ' Centre for Energy Studies, Indian Institute of Technology, Hauz Khas, New Delhi – 110016, India

Abstract: This paper analyses the temporal and spatial variation of Linke turbidity factor (TL) at five Indian stations; namely New Delhi, Kolkata, Poona, Jaipur and Mumbai. For computation of turbidity, data spanning eight years (1993-2000) for these stations has been procured from the Indian Meteorological Department (IMD) Poona. It is seen that turbidity values are low in winter, ranging from 4 to 6; and high in summer, ranging from 5 to 9. For the post-monsoon season, turbidity values are intermediate, ranging from 5 to 8. It is also seen that turbidity values highly depend on the pollution level of the station; e.g., Kolkata, being an industrialised city, has the highest value of turbidity - as high as 10.2 in May. For Poona, a relatively pollution-free city, the turbidity value is about 5.5 in May. Diurnal variation is small; it is about 14 % in winter and about 11.5% in summer for Poona. Regarding annual variation, it is seen that turbidity remains almost constant for all the years for two stations: Kolkata (TL = 7.5) and Poona (TL = 4.6). For the other three stations, Jaipur, New Delhi and Mumbai, the turbidity values are almost constant for the first 4 years (1993-1996) and then there is sharp increase in turbidity values during 1997 for Jaipur (TL = 6.4) and for New Delhi (TL = 6.8). Frequency distribution of turbidity values shows that most of the values lie between 3 and 10. For Kolkata maximum frequency, 37%, lies in the range 6.0-7.5; for New Delhi it is 46% and the range is 4.5-6.0.

Keywords: radiation; Linke turbidity factors; aerosols; optical depth; transmittance; India; air pollution; air quality; India.

DOI: 10.1504/IJEWM.2013.054705

International Journal of Environment and Waste Management, 2013 Vol.12 No.1, pp.52 - 64

Received: 19 Aug 2008
Accepted: 19 Jan 2009

Published online: 20 Sep 2014 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article