A wavelet-based spectral analysis of long-term time series of optical properties of aerosols obtained by lidar and radiometer measurements over an urban station in Western India

Abstract Over 700 weekly-spaced vertical profiles of aerosol number density have been archived during 14-year period (October 1986–September 2000) using a bi-static Argon ion lidar system at the Indian Institute of Tropical Meteorology, Pune (18°43′N, 73°51′E, 559 m above mean sea level), India. The monthly resolved time series of aerosol distributions within the atmospheric boundary layer as well as at different altitudes aloft have been subjected to the wavelet-based spectral analysis to investigate different characteristic periodicities present in the long-term dataset. The solar radiometric aerosol optical depth (AOD) measurements over the same place during 1998–2003 have also been analyzed with the wavelet technique. Wavelet spectra of both the time series exhibited significant quasi-annual (around 12–14 months) and quasi-biennial (around 22–25 months) oscillations at statistically significant level. An overview on the lidar and radiometric data sets including the wavelet-based spectral analysis procedure is also presented. A brief statistical analysis concerning both annual and interannual variability of lidar and radiometer derived aerosol distributions has been performed to delineate the effect of different dominant seasons and associated meteorological conditions prevailing over the experimental site in Western India. Additionally, the impact of urbanization on the long-term trends in the lidar measurements of aerosol loadings over the experimental site is brought out. This was achieved by using the lidar observations and a preliminary data set built for inferring the urban aspects of the city of Pune, which included population, number of industries and vehicles etc. in the city.

[1]  D. Jhurry,et al.  Aerosol optical depths over peninsular India and adjoining oceans during the INDOEX campaigns: Spatial, temporal, and spectral characteristics , 2001 .

[2]  Pcs Devara,et al.  Review article Remote sensing of atmospheric aerosols from active and passive optical techniques , 1998 .

[3]  Francesc Rocadenbosch,et al.  Cluster Analysis of 4-Day Back Trajectories Arriving in the Barcelona Area, Spain, from 1997 to 2002 , 2004 .

[4]  R. P. Kane Relationship between QBOs of stratospheric winds, ENSO variability and other atmospheric parameters , 1992 .

[5]  Glenn E. Shaw,et al.  Indian Ocean Experiment: An integrated analysis of the climate forcing and effects of the great Indo-Asian haze , 2001 .

[6]  P. Di Girolamo,et al.  Observation of convection initiation processes with a suite of state‐of‐the‐art research instruments during COPS IOP 8b , 2010 .

[7]  Volker Wulfmeyer,et al.  Elastic-backscatter-lidar-based characterization of the convective boundary layer and investigation of related statistics , 2010 .

[8]  Volker Wulfmeyer,et al.  3-dimensional observations of atmospheric variables during the field campaign COPS , 2008 .

[9]  G. Teschke,et al.  Extraction and Analysis of Structural Features in Cloud Radar and Lidar Data Using Wavelet Based Methods , 2002 .

[10]  G. Pandithurai,et al.  Aerosol-profile measurements in the lower troposphere with four-wavelength bistatic argon-ion lidar. , 1995, Applied optics.

[11]  Lonnie H. Hudgins,et al.  Wavelet transforms and atmopsheric turbulence. , 1993, Physical review letters.

[12]  M. Farge Wavelet Transforms and their Applications to Turbulence , 1992 .

[13]  F. Dominici,et al.  Fine particulate air pollution and mortality in 20 U.S. cities, 1987-1994. , 2000, The New England journal of medicine.

[14]  M. Andreae Chapter 10 – Climatic effects of changing atmospheric aerosol levels , 1995 .

[15]  I. Brooks,et al.  Finding Boundary Layer Top: Application of a Wavelet Covariance Transform to Lidar Backscatter Profiles , 2003 .

[16]  J. Rosen,et al.  Measured light-scattering properties of individual aerosol particles compared to mie scattering theory. , 1973, Applied optics.

[17]  J. Tukey,et al.  An algorithm for the machine calculation of complex Fourier series , 1965 .

[18]  Volker Wulfmeyer,et al.  A novel approach for the characterization of transport and optical properties of aerosol particles near sources – Part I: Measurement of particle backscatter coefficient maps with a scanning UV lidar , 2011 .

[19]  Lukas H. Meyer,et al.  Summary for Policymakers , 2022, The Ocean and Cryosphere in a Changing Climate.

[20]  P. R. C. Rahul,et al.  Evidence of Atmospheric Brown Clouds Over India During the 2009 Drought Year , 2012, IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing.

[21]  E. Dutton A coherence between the QBO and the amplitude of the Mauna Loa atmospheric transmission annual cycle , 1992 .

[22]  D. Winker,et al.  Overview of the CALIPSO Mission and CALIOP Data Processing Algorithms , 2009 .

[23]  Corinne Le Quéré,et al.  Climate Change 2013: The Physical Science Basis , 2013 .

[24]  M. G. Manoj,et al.  Quasi-periodic oscillations of aerosol backscatter profiles and surface meteorological parameters during winter nights over a tropical station , 2011 .

[25]  M. Memmesheimer,et al.  Modal aerosol dynamics model for Europe: development and first applications , 1998 .

[26]  P. Devara,et al.  Real-time monitoring of atmospheric aerosols using a computer-controlled lidar , 1995 .

[27]  Praveen Kumar,et al.  Wavelets in Geophysics , 1994 .

[28]  Martin Wild,et al.  Aerosol emissions and dimming/brightening in Europe: Sensitivity studies with ECHAM5-HAM , 2011 .

[29]  R. S. Maheskumar,et al.  Relationship between lidar‐based observations of aerosol content and monsoon precipitation over a tropical station, Pune, India , 2003 .

[30]  P. Raj,et al.  A lidar study of atmospheric aerosols during two contrasting monsoon seasons , 2009 .

[31]  J. O'Brien,et al.  An Introduction to Wavelet Analysis in Oceanography and Meteorology: With Application to the Dispersion of Yanai Waves , 1993 .

[32]  M. Kasahara Physical and Chemical Characteristics of Atmospheric Aerosols , 1996 .

[33]  Stéphane Mallat,et al.  Introduction to the special issue on wavelet transforms and multiresolution signal analysis , 1992, IEEE Transactions on Information Theory.

[34]  K. Moorthy,et al.  Interannual variations of aerosol optical depth over coastal India : Relation to synoptic meteorology , 2005 .

[35]  V. Ramaswamy,et al.  Anthropogenic Aerosols and the Weakening of the South Asian Summer Monsoon , 2011, Science.

[36]  Ingrid Daubechies,et al.  The wavelet transform, time-frequency localization and signal analysis , 1990, IEEE Trans. Inf. Theory.

[37]  B. A. Bodhaine,et al.  Seasonal variations in aerosols and atmospheric transmission at Mauna Loa Observatory , 1981 .

[38]  Dennis K. Killinger,et al.  Optical and laser remote sensing , 1983 .

[39]  J. Kiehl,et al.  Atmospheric brown clouds: impacts on South Asian climate and hydrological cycle. , 2005, Proceedings of the National Academy of Sciences of the United States of America.

[40]  T. Nakajima,et al.  Simultaneous determination of complex refractive index and size distribution of airborne and water-suspended particles from light scattering measurements. , 1982 .

[41]  P. Devara,et al.  Aerosol optical depth variability over Arabian Sea during drought and normal years of Indian monsoon , 2008 .

[42]  Margarete Oliveira Domingues,et al.  On wavelet techniques in atmospheric sciences , 2005 .

[43]  P. Devara,et al.  Lidar‐observed long‐term variations in urban aerosol characteristics and their connection with meteorological parameters , 1994 .

[44]  P. Devara,et al.  Aerosol size distribution and refractive index from bistatic lidar angular scattering measurements in the surface layer , 1996 .

[45]  V. Ramanathan,et al.  Winter to summer monsoon variation of aerosol optical depth over the tropical Indian Ocean , 2002 .

[46]  R. Vijayakumar,et al.  Study of surface ozone behaviour at urban and forested sites in India , 1995 .

[47]  L. J. Cox Optical Properties of the Atmosphere , 1979 .

[48]  S. Roy Impact of aerosol optical depth on seasonal temperatures in India: a spatio‐temporal analysis , 2008 .

[49]  M. Haeffelin,et al.  Spatio-temporal variability of the atmospheric boundary layer depth over the Paris agglomeration: An assessment of the impact of the urban heat island intensity , 2012 .

[50]  R. S. Maheskumar,et al.  Some features of columnar aerosol optical depth, ozone and precipitable water content observed over land during the INDOEX-IFP99 , 2001 .

[51]  S. Twomey,et al.  Aerosols, clouds and radiation , 1991 .

[52]  Lidar measurements of aerosol column content in an urban nocturnal boundary layer , 1997 .

[53]  C. Tucker,et al.  Evidence for a significant urbanization effect on climate in China. , 2004, Proceedings of the National Academy of Sciences of the United States of America.

[54]  S. Babu,et al.  Quasi‐biennial oscillations in spectral aerosol optical depth , 2009 .

[55]  S. K. Satheesh,et al.  Weekly periodicities of aerosol properties observed at an urban location in India , 2011 .

[56]  R. S. Maheskumar,et al.  Recent trends in aerosol climatology and air pollution as inferred from multi‐year lidar observations over a tropical urban station , 2002 .

[57]  K. Tung,et al.  Modulation of the Period of the Quasi-Biennial Oscillation by the Solar Cycle , 2009 .

[58]  R. J. Reed The Quasi-Biennial Oscillation of the Atmosphere Between 30 and 50 km Over Ascension Island , 1965 .

[59]  V. Khokhlov,et al.  NAO-induced spatial variations of total ozone column over Europe at near-synoptic time scale , 2011 .

[60]  C. Torrence,et al.  A Practical Guide to Wavelet Analysis. , 1998 .

[61]  R. Charlson,et al.  Direct climate forcing by anthropogenic aerosols : Quantifying the link between atmospheric sulfate and radiation , 1999 .

[62]  Application of wavelet transformation to determine wavelengths and phase velocities of gravity waves observed by lidar measurements , 2007 .

[63]  P. Devara,et al.  Study of successive contrasting monsoons (2001–2002) in terms of aerosol variability over a tropical station Pune, India , 2009 .