在与地球大气层相关的条件下,立方冰的形成
Benjamin J Murray1, Daniel A Knopf, Allan K Bertram
1Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada.
Nature
|March 11, 2005
概括
实验室实验表明,立方体冰是在190K以下的纯水滴中形成的. 这一发现对于理解大气冰云及其对地球气候的潜在影响至关重要.
科学领域:
- 大气化学 大气化学
- 晶体学 晶体学是指结晶学.
- 地质物理学 地质物理学
背景情况:
- 大气中的水滴中冰的均核形成通常形成六角冰.
- 以前的报道表明,地球大气层中可能会形成立方体冰.
研究的目的:
- 在大气条件下研究纯水和水溶液滴中的立方冰的形成.
- 为了确定温度范围和有利于立方体冰形成的条件.
主要方法:
- 实验室实验涉及微米大小的水滴的均质核化.
- 控制的冷却速度模仿大气条件.
- 冰晶阶段形成的分析.
主要成果:
- 在纯水和水溶液液滴中观察到立方体冰的形成,均地结.
- 在低于190K的温度下,立方体冰形成占主导地位.
- 这种温度范围适用于极地平流层云和热带热带层云.
结论:
- 在特定的条件下,立方体冰可以在地球大气层中形成.
- 立方冰的存在可能会改变云微物理,水蒸气压力和冰颗粒大小分布.
- 这可能会导致热带期地区的脱水增加.
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