Open AccessInterrelationships between aerosol characteristics and light scattering during late winter in an Eastern Mediterranean arid environment
Author(s) -
Ichoku Charles,
Andreae Meinrat O.,
Andreae Tracey W.,
Meixner Franz X.,
Schebeske Guenther,
Formenti Paola,
Maenhaut Willy,
Cafmeyer Jan,
Ptasinski Jacek,
Karnieli Ar,
Orlovsky Leah
Publication year - 1999
Publication title -
journal of geophysical research: atmospheres
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/1999jd900781
Subject(s) - aerosol , nephelometer , atmospheric sciences , radiative forcing , mineral dust , environmental science , turbidity , single scattering albedo , aeronet , radiative transfer , mineralogy , scattering , meteorology , light scattering , chemistry , geology , physics , oceanography , optics
An intensive field campaign involving measurement of various aerosol physical, chemical, and radiative properties was conducted at Sde Boker (also written as Sede Boqer) in the Negev Desert of Israel, from 18 February to 15 March 1997. Nephelometer measurements gave average background scattering coefficient values of about 25 Mm −1 at 550 nm wavelength, but strong dust events caused the value of this parameter to rise up to about 800 Mm −1 . Backscattering fractions did not depend on aerosol loading and generally fell in the range of 0.1 to 0.25, comparable to values reported for marine and Arctic environments. Chemical analysis of the aerosol revealed that in the coarse size range (2–10 μm equivalent aerodynamic diameter (EAD)), calcium (Ca) was by far the most abundant element followed by silicon (Si), both of which are indicators for mineral dust. In the fine size fraction (<2 μm EAD), sulfur (S) generally was the dominant element, except during high dust episodes when Ca and Si were again the most abundant. Furthermore, fine black carbon (BC) correlates with S, suggesting that they may have originated from the same sources or source regions. An indication of the short‐term effect of aerosol loading on radiative forcing was provided by measurements of global and diffuse solar radiation, which showed that during high‐turbidity periods (strong dust events), almost all of the solar radiation reaching the area is scattered or absorbed.