The spectral albedo of sea ice and salt crusts on the tropical ocean of Snowball Earth: 1. Laboratory measurements
| العنوان: | The spectral albedo of sea ice and salt crusts on the tropical ocean of Snowball Earth: 1. Laboratory measurements |
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| المؤلفون: | Bonnie Light, Stephen G. Warren, Regina C. Carns |
| المصدر: | Journal of Geophysical Research: Oceans. 121:4966-4979 |
| بيانات النشر: | American Geophysical Union (AGU), 2016. |
| سنة النشر: | 2016 |
| مصطلحات موضوعية: | geography, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, Earth science, Mineralogy, 010502 geochemistry & geophysics, Oceanography, 01 natural sciences, Arctic ice pack, Brinicle, Geophysics, Sea ice growth processes, Space and Planetary Science, Geochemistry and Petrology, Sea ice thickness, Earth and Planetary Sciences (miscellaneous), Melt pond, Sea ice, Cryosphere, Snowball Earth, Geology, 0105 earth and related environmental sciences |
| الوصف: | The ice-albedo feedback mechanism likely contributed to global glaciation during the Snowball Earth events of the Neoproterozoic era (1 Ga to 544 Ma). This feedback results from the albedo contrast between sea ice and open ocean. Little is known about the optical properties of some of the possible surface types that may have been present, including sea ice that is both snow-free and cold enough for salts to precipitate within brine inclusions. A proxy surface for such ice was grown in a freezer laboratory using the single salt NaCl and kept below the eutectic temperature (−21.2°C) of the NaCl-H2O binary system. The resulting ice cover was composed of ice and precipitated hydrohalite crystals (NaCl · 2H2O). As the cold ice sublimated, a thin lag-deposit of salt formed on the surface. To hasten its growth in the laboratory, the deposit was augmented by addition of a salt-enriched surface crust. Measurements of the spectral albedo of this surface were carried out over 90 days as the hydrohalite crust thickened due to sublimation of ice, and subsequently over several hours as the crust warmed and dissolved, finally resulting in a surface with puddled liquid brine. The all-wave solar albedo of the subeutectic crust is 0.93 (in contrast to 0.83 for fresh snow and 0.67 for melting bare sea ice). Incorporation of these processes into a climate model of Snowball Earth will result in a positive salt-albedo feedback operating between −21°C and −36°C. |
| تدمد: | 2169-9291 2169-9275 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_________::d5e557b013d454764da7e21ad80902d9 https://doi.org/10.1002/2016jc011803 |
| حقوق: | CLOSED |
| رقم الأكسشن: | edsair.doi...........d5e557b013d454764da7e21ad80902d9 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 21699291 21699275 |
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