Development and calibration of an automatic spectral albedometer to estimate near-surface snow SSA time series
Spectral albedo of the snow surface in the visible/near-infrared range has been measured for 3 years by an automatic spectral radiometer installed at Dome C (75° S, 123° E) in Antarctica in order to retrieve the specific surface area (SSA) of superficial snow. This study focuses on the uncertainties...
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2016
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fttriple:oai:gotriple.eu:oai:doaj.org/article:30b8908795d04587a368e38d45689b12 2023-05-15T13:53:01+02:00 Development and calibration of an automatic spectral albedometer to estimate near-surface snow SSA time series G. Picard Q. Libois L. Arnaud G. Verin M. Dumont 2016-06-01 https://doi.org/10.5194/tc-10-1297-2016 http://www.the-cryosphere.net/10/1297/2016/tc-10-1297-2016.pdf https://doaj.org/article/30b8908795d04587a368e38d45689b12 en eng Copernicus Publications 1994-0416 1994-0424 doi:10.5194/tc-10-1297-2016 http://www.the-cryosphere.net/10/1297/2016/tc-10-1297-2016.pdf https://doaj.org/article/30b8908795d04587a368e38d45689b12 undefined The Cryosphere, Vol 10, Iss 3, Pp 1297-1316 (2016) geo envir Journal Article https://vocabularies.coar-repositories.org/resource_types/c_6501/ 2016 fttriple https://doi.org/10.5194/tc-10-1297-2016 2023-01-22T19:11:24Z Spectral albedo of the snow surface in the visible/near-infrared range has been measured for 3 years by an automatic spectral radiometer installed at Dome C (75° S, 123° E) in Antarctica in order to retrieve the specific surface area (SSA) of superficial snow. This study focuses on the uncertainties of the SSA retrieval due to instrumental and data processing limitations. We find that when the solar zenith angle is high, the main source of uncertainties is the imperfect angular response of the light collectors. This imperfection introduces a small spurious wavelength-dependent trend in the albedo spectra which greatly affects the SSA retrieval. By modeling this effect, we show that for typical snow and illumination conditions encountered at Dome C, retrieving SSA with an accuracy better than 15 % (our target) requires the difference of response between 400 and 1100 nm to not exceed 2 %. Such a small difference can be achieved only by (i) a careful design of the collectors, (ii) an ad hoc correction of the spectra using the actual measured angular response of the collectors, and (iii) for solar zenith angles less than 75°. The 3-year time series of retrieved SSA features a 3-fold decrease every summer which is significantly larger than the estimated uncertainties. This highlights the high dynamics of near-surface SSA at Dome C. Article in Journal/Newspaper Antarc* Antarctica The Cryosphere Unknown The Cryosphere 10 3 1297 1316 |
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geo envir G. Picard Q. Libois L. Arnaud G. Verin M. Dumont Development and calibration of an automatic spectral albedometer to estimate near-surface snow SSA time series |
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geo envir |
description |
Spectral albedo of the snow surface in the visible/near-infrared range has been measured for 3 years by an automatic spectral radiometer installed at Dome C (75° S, 123° E) in Antarctica in order to retrieve the specific surface area (SSA) of superficial snow. This study focuses on the uncertainties of the SSA retrieval due to instrumental and data processing limitations. We find that when the solar zenith angle is high, the main source of uncertainties is the imperfect angular response of the light collectors. This imperfection introduces a small spurious wavelength-dependent trend in the albedo spectra which greatly affects the SSA retrieval. By modeling this effect, we show that for typical snow and illumination conditions encountered at Dome C, retrieving SSA with an accuracy better than 15 % (our target) requires the difference of response between 400 and 1100 nm to not exceed 2 %. Such a small difference can be achieved only by (i) a careful design of the collectors, (ii) an ad hoc correction of the spectra using the actual measured angular response of the collectors, and (iii) for solar zenith angles less than 75°. The 3-year time series of retrieved SSA features a 3-fold decrease every summer which is significantly larger than the estimated uncertainties. This highlights the high dynamics of near-surface SSA at Dome C. |
format |
Article in Journal/Newspaper |
author |
G. Picard Q. Libois L. Arnaud G. Verin M. Dumont |
author_facet |
G. Picard Q. Libois L. Arnaud G. Verin M. Dumont |
author_sort |
G. Picard |
title |
Development and calibration of an automatic spectral albedometer to estimate near-surface snow SSA time series |
title_short |
Development and calibration of an automatic spectral albedometer to estimate near-surface snow SSA time series |
title_full |
Development and calibration of an automatic spectral albedometer to estimate near-surface snow SSA time series |
title_fullStr |
Development and calibration of an automatic spectral albedometer to estimate near-surface snow SSA time series |
title_full_unstemmed |
Development and calibration of an automatic spectral albedometer to estimate near-surface snow SSA time series |
title_sort |
development and calibration of an automatic spectral albedometer to estimate near-surface snow ssa time series |
publisher |
Copernicus Publications |
publishDate |
2016 |
url |
https://doi.org/10.5194/tc-10-1297-2016 http://www.the-cryosphere.net/10/1297/2016/tc-10-1297-2016.pdf https://doaj.org/article/30b8908795d04587a368e38d45689b12 |
genre |
Antarc* Antarctica The Cryosphere |
genre_facet |
Antarc* Antarctica The Cryosphere |
op_source |
The Cryosphere, Vol 10, Iss 3, Pp 1297-1316 (2016) |
op_relation |
1994-0416 1994-0424 doi:10.5194/tc-10-1297-2016 http://www.the-cryosphere.net/10/1297/2016/tc-10-1297-2016.pdf https://doaj.org/article/30b8908795d04587a368e38d45689b12 |
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undefined |
op_doi |
https://doi.org/10.5194/tc-10-1297-2016 |
container_title |
The Cryosphere |
container_volume |
10 |
container_issue |
3 |
container_start_page |
1297 |
op_container_end_page |
1316 |
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