Solar irradiance at the earth's surface: long-term behavior observed at the South Pole
This research examines a 17-year database of UV-A (320–400 nm) and visible (400–600 nm) solar irradiance obtained by a scanning spectroradiometer located at the South Pole. The goal is to define the variability in solar irradiance reaching the polar surface, with emphasis on the influence of cloudin...
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ftdoajarticles:oai:doaj.org/article:66051be85fc8466e8df45d62364e30e7 2023-05-15T18:22:14+02:00 Solar irradiance at the earth's surface: long-term behavior observed at the South Pole J. E. Frederick A. L. Hodge 2011-02-01T00:00:00Z https://doi.org/10.5194/acp-11-1177-2011 https://doaj.org/article/66051be85fc8466e8df45d62364e30e7 EN eng Copernicus Publications http://www.atmos-chem-phys.net/11/1177/2011/acp-11-1177-2011.pdf https://doaj.org/toc/1680-7316 https://doaj.org/toc/1680-7324 doi:10.5194/acp-11-1177-2011 1680-7316 1680-7324 https://doaj.org/article/66051be85fc8466e8df45d62364e30e7 Atmospheric Chemistry and Physics, Vol 11, Iss 3, Pp 1177-1189 (2011) Physics QC1-999 Chemistry QD1-999 article 2011 ftdoajarticles https://doi.org/10.5194/acp-11-1177-2011 2022-12-31T08:50:54Z This research examines a 17-year database of UV-A (320–400 nm) and visible (400–600 nm) solar irradiance obtained by a scanning spectroradiometer located at the South Pole. The goal is to define the variability in solar irradiance reaching the polar surface, with emphasis on the influence of cloudiness and on identifying systematic trends and possible links to the solar cycle. To eliminate changes associated with the varying solar elevation, the analysis focuses on data averaged over 30–35 day periods centered on each year's austral summer solstice. The long-term average effect of South Polar clouds is a small attenuation, with the mean measured irradiances being about 5–6% less than the clear-sky values, although at any specific time clouds may reduce or enhance the signal that reaches the sensor. The instantaneous fractional attenuation or enhancement is wavelength dependent, where the percent deviation from the clear-sky irradiance at 400–600 nm is typically 2.5 times that at 320–340 nm. When averaged over the period near each year's summer solstice, significant correlations appear between irradiances at all wavelengths and the solar cycle as measured by the 10.7 cm solar radio flux. An approximate 1.8 ± 1.0% decrease in ground-level irradiance occurs from solar maximum to solar minimum for the wavelength band 320–400 nm. The corresponding decrease for 400–600 nm is 2.4 ± 1.9%. The best-estimate declines appear too large to originate in the sun. If the correlations have a geophysical origin, they suggest a small variation in atmospheric attenuation with the solar cycle over the period of observation, with the greatest attenuation occurring at solar minimum. Article in Journal/Newspaper South pole Directory of Open Access Journals: DOAJ Articles Austral South Pole Atmospheric Chemistry and Physics 11 3 1177 1189 |
institution |
Open Polar |
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Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Physics QC1-999 Chemistry QD1-999 |
spellingShingle |
Physics QC1-999 Chemistry QD1-999 J. E. Frederick A. L. Hodge Solar irradiance at the earth's surface: long-term behavior observed at the South Pole |
topic_facet |
Physics QC1-999 Chemistry QD1-999 |
description |
This research examines a 17-year database of UV-A (320–400 nm) and visible (400–600 nm) solar irradiance obtained by a scanning spectroradiometer located at the South Pole. The goal is to define the variability in solar irradiance reaching the polar surface, with emphasis on the influence of cloudiness and on identifying systematic trends and possible links to the solar cycle. To eliminate changes associated with the varying solar elevation, the analysis focuses on data averaged over 30–35 day periods centered on each year's austral summer solstice. The long-term average effect of South Polar clouds is a small attenuation, with the mean measured irradiances being about 5–6% less than the clear-sky values, although at any specific time clouds may reduce or enhance the signal that reaches the sensor. The instantaneous fractional attenuation or enhancement is wavelength dependent, where the percent deviation from the clear-sky irradiance at 400–600 nm is typically 2.5 times that at 320–340 nm. When averaged over the period near each year's summer solstice, significant correlations appear between irradiances at all wavelengths and the solar cycle as measured by the 10.7 cm solar radio flux. An approximate 1.8 ± 1.0% decrease in ground-level irradiance occurs from solar maximum to solar minimum for the wavelength band 320–400 nm. The corresponding decrease for 400–600 nm is 2.4 ± 1.9%. The best-estimate declines appear too large to originate in the sun. If the correlations have a geophysical origin, they suggest a small variation in atmospheric attenuation with the solar cycle over the period of observation, with the greatest attenuation occurring at solar minimum. |
format |
Article in Journal/Newspaper |
author |
J. E. Frederick A. L. Hodge |
author_facet |
J. E. Frederick A. L. Hodge |
author_sort |
J. E. Frederick |
title |
Solar irradiance at the earth's surface: long-term behavior observed at the South Pole |
title_short |
Solar irradiance at the earth's surface: long-term behavior observed at the South Pole |
title_full |
Solar irradiance at the earth's surface: long-term behavior observed at the South Pole |
title_fullStr |
Solar irradiance at the earth's surface: long-term behavior observed at the South Pole |
title_full_unstemmed |
Solar irradiance at the earth's surface: long-term behavior observed at the South Pole |
title_sort |
solar irradiance at the earth's surface: long-term behavior observed at the south pole |
publisher |
Copernicus Publications |
publishDate |
2011 |
url |
https://doi.org/10.5194/acp-11-1177-2011 https://doaj.org/article/66051be85fc8466e8df45d62364e30e7 |
geographic |
Austral South Pole |
geographic_facet |
Austral South Pole |
genre |
South pole |
genre_facet |
South pole |
op_source |
Atmospheric Chemistry and Physics, Vol 11, Iss 3, Pp 1177-1189 (2011) |
op_relation |
http://www.atmos-chem-phys.net/11/1177/2011/acp-11-1177-2011.pdf https://doaj.org/toc/1680-7316 https://doaj.org/toc/1680-7324 doi:10.5194/acp-11-1177-2011 1680-7316 1680-7324 https://doaj.org/article/66051be85fc8466e8df45d62364e30e7 |
op_doi |
https://doi.org/10.5194/acp-11-1177-2011 |
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Atmospheric Chemistry and Physics |
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11 |
container_issue |
3 |
container_start_page |
1177 |
op_container_end_page |
1189 |
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