Effective aerosol optical depth from pyranometer measurements of surface  solar radiation (global radiation) at Thessaloniki, Greece

Abstract. Pyranometer measurements of the solar surface radiation (SSR) are available at many locations worldwide, often as long time series covering several decades into the past. These data constitute a potential source of information on the atmospheric aerosol load. Here, we present a method for estimating the aerosol optical depth (AOD) using pyranometer measurements of the SSR together with total water vapor column information. The method, which is based on radiative transfer simulations, was developed and tested using recent data from Thessaloniki, Greece. The effective AOD calculated using this method was found to agree well with co-located AERONET measurements, exhibiting a correlation coefficient of 0.9 with 2/3 of the data found within ±20% or ±0.05 of the AERONET AOD. This is similar to the performance of current satellite aerosol methods. Differences in the AOD as compared to AERONET can be explained by variations in the aerosol properties of the atmosphere that are not accounted for in the idealized settings used in the radiative transfer simulations, such as variations in the single scattering albedo and Ångström exponent. Furthermore, the method is sensitive to calibration offsets between the radiative transfer simulations and the pyranometer SSR. The method provides an opportunity of extending our knowledge of the atmospheric aerosol load to locations and times not covered by dedicated aerosol measurements.

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Long-time global radiation for Central Europe derived from ISCCP Dx data

Atmospheric Chemistry and Physics ◽

10.5194/acp-7-5021-2007 ◽

2007 ◽

Vol 7 (18) ◽

pp. 5021-5032 ◽

Cited By ~ 5

Author(s):

N. Petrenz ◽

M. Sommer ◽

F. H. Berger

Keyword(s):

Radiative Transfer ◽

Central Europe ◽

Climate Models ◽

Regional Climate ◽

Global Radiation ◽

Surface Radiation ◽

Radiation Budget ◽

Data Set ◽

Look Up Table ◽

Long Time

Abstract. The global Dx dataset of the International Satellite Cloud Climatology Project (ISCCP) with a spatial resolution of about 30×30 km² was analysed to produce spatially highly resolved long-time datasets to describe the radiation budget for Central Europe over the period of 1984–2000. The computation of shortwave and longwave radiant flux densities at top of atmosphere and at surface was based on 1D radiative transfer simulations. The simulations were carried out for all relevant atmospheric and surface conditions and the results were inserted into a look-up table. Thus, long-time calculations for all conditions and time slices of the Dx dataset could be realised. The study is focussed on the global radiation at surface. The first examination was carried out for the ISCCP D1 and the ISCCP D2 dataset. These datasets, including cloud and surface information on a different spatial scale (280×280 km2), were applied to the produced look-up table analogue to the Dx data. The calculated global radiation of the D1 and D2 dataset were compared to the Dx dataset. The differences between these datasets mainly range from 5–15 Wm−2 (2–6%) with regional peaks up to 25 Wm−2 (10%). The evaluation with the GEWEX Surface Radiation Budget (SRB) data emphasises differences between 5–25 Wm−2 (6–16%) over land areas. Deviations to an ISCCP provided flux data set vary from 0 Wm−2 in the North up to 35 Wm−2 (0–13%) in the South of Central Europe. The global radiation datasets provided by the Global Energy Balance Archive (GEBA) and the German Meteorological Service (DWD) agree well, but they are 5–25 Wm−2 (7–10%) lower than the Dx results. Annual analyses of global radiation of various regional climate models complete the study. It is figured out that the used models and methods reveal a couple of discrepancies. Especially in wintertime the results of our analysis differ to the considered models. Principally the uncertainties were caused by the determined range of values and simplifications for the computation of the radiative transfer simulation.

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Implementation of simple model for atmospheric radiative transfer code in single scattering approximation for retrieval of aerosol optical depth over Dehradun, India

Journal of Applied Remote Sensing ◽

10.1117/1.jrs.7.073521 ◽

2013 ◽

Vol 7 (1) ◽

pp. 073521 ◽

Cited By ~ 1

Author(s):

Manu Mehta ◽

Payal Goyal ◽

Kautilya Nishant

Keyword(s):

Simple Model ◽

Radiative Transfer ◽

Aerosol Optical Depth ◽

Optical Depth ◽

Single Scattering ◽

Scattering Approximation ◽

Atmospheric Radiative Transfer ◽

Single Scattering Approximation

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Long-time global radiation for Central Europe derived from ISCCP Dx data

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-7-8333-2007 ◽

2007 ◽

Vol 7 (3) ◽

pp. 8333-8360

Author(s):

N. Petrenz ◽

M. Sommer ◽

F. H. Berger

Keyword(s):

Radiative Transfer ◽

Central Europe ◽

Climate Models ◽

Regional Climate ◽

Global Radiation ◽

Surface Radiation ◽

Radiation Budget ◽

Data Set ◽

Look Up Table ◽

Long Time

Abstract. The global Dx dataset of the "International Satellite Cloud Climatology Project" (ISCCP) with a spatial resolution of about 30×30 km2 was analysed to produce spatially highly resolved long-time datasets to describe the radiation budget for Central Europe over the period of 1984–2000. The computation of shortwave and longwave radiant flux densities at top of atmosphere and at surface was based on 1-D radiative transfer simulations. The simulations were carried out for all relevant atmospheric and surface conditions and the results were inserted into a look-up table. Thus, long-time calculations for all conditions and time slices of the Dx dataset could be realised. The study is focussed on the global radiation at surface. The first examination was carried out for the ISCCP D1 and the ISCCP D2 dataset. These datasets, including cloud and surface information on a different spatial scale (280×280 km2), were applied to the produced look-up table analogue to the Dx data. The calculated global radiation of the D1 and D2 dataset were compared to the Dx dataset. The differences between these datasets mainly range from 5–15 W m−2 (2–6%) with regional peaks up to 25 W m−2 (10%). The evaluation with the GEWEX "Surface Radiation Budget" (SRB) data emphasises differ-ences between 5–25 W m−2 (6–16%) over land areas. Deviations to an ISCCP provided flux data set vary from 0 W m−2 in the North up to 35 W m−2 (0–13%) in the South of Central Europe. The global radiation datasets provided by the "Global Energy Balance Archive" (GEBA) and the "German Meteorological Service" (DWD) agree well, but they are 5–25 W m−2 (7–10%) lower than the Dx results. Annual analyses of global radiation of various regional climate models complete the study. It is figured out that the used models and methods reveal a couple of discrepancies. Especially in wintertime the results of our analysis differ to the considered models. Principally the uncer-tainties were caused by the determined range of values and simplifications for the computation of the radiative transfer simulation.

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Finely and coarsely dispersed components of atmospheric aerosol optical depth in maritime and polar regions

Оптика атмосферы и океана ◽

10.15372/aoo20150803 ◽

2015 ◽

Vol 28 (8) ◽

Keyword(s):

Aerosol Optical Depth ◽

Optical Depth ◽

Atmospheric Aerosol ◽

Polar Regions

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Generalization of results of measurements of atmospheric aerosol optical depth on Spitsbergen Archipelago in 2011-2016

Оптика атмосферы и океана ◽

10.15372/aoo20171107 ◽

2017 ◽

Cited By ~ 1

Keyword(s):

Aerosol Optical Depth ◽

Optical Depth ◽

Atmospheric Aerosol

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Retrieval of aerosol single-scattering albedo and polarized phase function from polarized sun-photometer measurements for Zanjan's atmosphere

Atmospheric Measurement Techniques ◽

10.5194/amt-6-2659-2013 ◽

2013 ◽

Vol 6 (10) ◽

pp. 2659-2669 ◽

Cited By ~ 12

Author(s):

A. Bayat ◽

H. R. Khalesifard ◽

A. Masoumi

Keyword(s):

Aerosol Optical Depth ◽

Optical Depth ◽

Atmospheric Aerosols ◽

Phase Function ◽

Single Scattering ◽

Single Scattering Albedo ◽

Angstrom Exponent ◽

Ångström Exponent ◽

Sun Photometer ◽

Ångstrom Exponent

Abstract. The polarized phase function of atmospheric aerosols has been investigated for the atmosphere of Zanjan, a city in northwest Iran. To do this, aerosol optical depth, Ångström exponent, single-scattering albedo, and polarized phase function have been retrieved from the measurements of a Cimel CE 318-2 polarized sun-photometer from February 2010 to December 2012. The results show that the maximum value of aerosol polarized phase function as well as the polarized phase function retrieved for a specific scattering angle (i.e., 60°) are strongly correlated (R = 0.95 and 0.95, respectively) with the Ångström exponent. The latter has a meaningful variation with respect to the changes in the complex refractive index of the atmospheric aerosols. Furthermore the polarized phase function shows a moderate negative correlation with respect to the atmospheric aerosol optical depth and single-scattering albedo (R = −0.76 and −0.33, respectively). Therefore the polarized phase function can be regarded as a key parameter to characterize the atmospheric particles of the region – a populated city in the semi-arid area and surrounded by some dust sources of the Earth's dust belt.

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