Abstract

We describe a method to infer total ozone abundance and effective cloud transmission from global (diffuse plus direct) spectral irradiance measurements taken at the Earth's surface. The derivation of total ozone abundance relies on the comparison of measured irradiance ratios at two wavelengths in the UV part of the spectrum with a synthetic chart of this ratio computed for a variety of ozone abundances. One of these wavelengths should be appreciably absorbed by ozone (e.g., 305 nm) compared with the other one (e.g., 340 nm). This synthetic ratio (and therefore also the inferred total ozone abundance) is insensitive to the value of the surface albedo used in the model computations. Comparison with independent in situ and remote (from ground and space) determinations of total ozone abundance shows that measurements of global irradiances provide a reliable means of inferring the total column ozone amount for clear as well as cloudy sky conditions. Computer simulations are used to demonstrate that the ozone abundance inferred from global irradiance measurements is quite insensitive to cloud effects, whereas the use of the scattered irradiance only or the zenith sky intensity (measured routinely in the Dobson network on overcast days) requires substantial corrections for cloud effects. Effective cloud transmission is estimated from the data by comparing the measured irradiance at a wavelength where ozone absorption is minimal (e.g., 350 nm) to the clear-sky value. Irradiances generated by a plane-parallel radiation model as a function of cloud optical thickness are used to estimate an equivalent stratified cloud optical depth. These estimates of cloud transmission and optical depth are sensitive to ground reflection, implying that the accurate determination of cloud attenuation requires precise knowledge of the surface albedo.

© 1991 Optical Society of America

Full Article  |  PDF Article
OSA Recommended Articles
Comparison of column ozone retrievals by use of an UV multifilter rotating shadow-band radiometer with those from Brewer and Dobson spectrophotometers

James Slusser, James Gibson, David Bigelow, Donald Kolinski, Wanfeng Mou, Gloria Koenig, and Arthur Beaubien
Appl. Opt. 38(9) 1543-1551 (1999)

Analysis of direct solar ultraviolet irradiance measurements in the French Alps. Retrieval of turbidity and ozone column amount

Jacqueline Lenoble, Alain de la Casinière, and Thierry Cabot
Appl. Opt. 43(15) 3133-3139 (2004)

References

You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Figures (10)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Metrics

You do not have subscription access to this journal. Article level metrics are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription