Field investigations of apparent optical properties of ice cover in Finnish and Estonian lakes in winter 2009
A field programme on light conditions in ice-covered lakes and optical properties of lake ice was performed in seven lakes of Finland and Estonia in February–April 2009. On the basis of irradiance measurements above and below ice, spectral reflectance and transmittance were determined for the ice sh...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Estonian Academy Publishers
2011-03-01
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| Series: | Estonian Journal of Earth Sciences |
| Subjects: | |
| Online Access: | http://www.kirj.ee/public/Estonian_Journal_of_Earth_Sciences/2011/issue_1/earth-2011-1-50-64.pdf |
| _version_ | 1818673119456395264 |
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| author | Ruibo Lei Matti Leppäranta Ants Erm Elina Jaatinen Ove Pärn |
| author_facet | Ruibo Lei Matti Leppäranta Ants Erm Elina Jaatinen Ove Pärn |
| author_sort | Ruibo Lei |
| collection | DOAJ |
| description | A field programme on light conditions in ice-covered lakes and optical properties of lake ice was performed in seven lakes of Finland and Estonia in February–April 2009. On the basis of irradiance measurements above and below ice, spectral reflectance and transmittance were determined for the ice sheet; time evolution of photosynthetically active radiation (PAR) transmittance was examined from irradiance recordings at several levels inside the ice sheet. Snow cover was the dominant factor for transmission of PAR into the lake water body. Reflectance was 0.74–0.92 in winter, going down to 0.18–0.22 in the melting season. The bulk attenuation coefficient of dry snow was 14–25 m–1; the level decreased as the spring was coming. The reflectance and bulk attenuation coefficient of snow-free ice were 0.1–0.4 and 1–5 m–1. Both were considerably smaller than those of snow cover. Seasonal evolution of light transmission was mainly due to snow melting. Snow and ice cover not only depress the PAR level in a lake but also influence the spectral and directional distribution of light. |
| first_indexed | 2024-12-17T07:50:43Z |
| format | Article |
| id | doaj.art-43cd6612a48e43b8865593626e6967c4 |
| institution | Directory Open Access Journal |
| issn | 1736-4728 |
| language | English |
| last_indexed | 2024-12-17T07:50:43Z |
| publishDate | 2011-03-01 |
| publisher | Estonian Academy Publishers |
| record_format | Article |
| series | Estonian Journal of Earth Sciences |
| spelling | doaj.art-43cd6612a48e43b8865593626e6967c42022-12-21T21:57:51ZengEstonian Academy PublishersEstonian Journal of Earth Sciences1736-47282011-03-01601506410.3176/earth.2011.1.05Field investigations of apparent optical properties of ice cover in Finnish and Estonian lakes in winter 2009Ruibo LeiMatti LeppärantaAnts ErmElina JaatinenOve PärnA field programme on light conditions in ice-covered lakes and optical properties of lake ice was performed in seven lakes of Finland and Estonia in February–April 2009. On the basis of irradiance measurements above and below ice, spectral reflectance and transmittance were determined for the ice sheet; time evolution of photosynthetically active radiation (PAR) transmittance was examined from irradiance recordings at several levels inside the ice sheet. Snow cover was the dominant factor for transmission of PAR into the lake water body. Reflectance was 0.74–0.92 in winter, going down to 0.18–0.22 in the melting season. The bulk attenuation coefficient of dry snow was 14–25 m–1; the level decreased as the spring was coming. The reflectance and bulk attenuation coefficient of snow-free ice were 0.1–0.4 and 1–5 m–1. Both were considerably smaller than those of snow cover. Seasonal evolution of light transmission was mainly due to snow melting. Snow and ice cover not only depress the PAR level in a lake but also influence the spectral and directional distribution of light.http://www.kirj.ee/public/Estonian_Journal_of_Earth_Sciences/2011/issue_1/earth-2011-1-50-64.pdflake icesnowopticsreflectancetransmittanceattenuation coefficient. |
| spellingShingle | Ruibo Lei Matti Leppäranta Ants Erm Elina Jaatinen Ove Pärn Field investigations of apparent optical properties of ice cover in Finnish and Estonian lakes in winter 2009 Estonian Journal of Earth Sciences lake ice snow optics reflectance transmittance attenuation coefficient. |
| title | Field investigations of apparent optical properties of ice cover in Finnish and Estonian lakes in winter 2009 |
| title_full | Field investigations of apparent optical properties of ice cover in Finnish and Estonian lakes in winter 2009 |
| title_fullStr | Field investigations of apparent optical properties of ice cover in Finnish and Estonian lakes in winter 2009 |
| title_full_unstemmed | Field investigations of apparent optical properties of ice cover in Finnish and Estonian lakes in winter 2009 |
| title_short | Field investigations of apparent optical properties of ice cover in Finnish and Estonian lakes in winter 2009 |
| title_sort | field investigations of apparent optical properties of ice cover in finnish and estonian lakes in winter 2009 |
| topic | lake ice snow optics reflectance transmittance attenuation coefficient. |
| url | http://www.kirj.ee/public/Estonian_Journal_of_Earth_Sciences/2011/issue_1/earth-2011-1-50-64.pdf |
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