Calcium Chemistry in the Upper Atmosphere.

高层大气中的钙化学。

• 批准号: NE/B00015X/2
• 负责人: John Plane
• 金额: $ 4.38万
• 依托单位: University of Leeds
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2006
• 资助国家: 英国
• 起止时间: 2006 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FB00015X%2F2
• 关键词: Calcium; Chemistry; Upper; Atmosphere.

About 100 tonnes of extra-terrestrial dust enters the earth's atmosphere each day. Because of the high entry velocity (11 - 72 km/s), most of the material ablates, giving rise to layers of metal atoms between 80 and 105 km. A number of these metals (Na, Fe, K and Ca) can be observed from the ground using lidar (laser radar), providing an important tool for studying the physics and chemistry of this transition region on the edge of space. A long-running mystery is why the Ca layer is severely depleted, containing less than 1% of the expected density. The proposed project will address this question by first studying the reactions that control calcium chemistry in the upper mesosphere, and then constructing a model that includes a detailed description of the process of meteor ablation. This model will be tested against lidar measurements of Ca atoms and Ca+ ions, from two observatories at low and mid latitudes. The model and lidar data will also be used to study the chemistry of sporadic E layers, which are concentrated layers of metallic ions and electrons that have a significant effect on radio propagation. A particular goal is to predict the lifetimes of these layers.

每天大约有100吨地外尘埃进入地球大气层。由于进入速度很高（11 - 72公里/秒），大部分材料烧蚀，在80 - 105公里之间产生金属原子层。其中一些金属（Na、Fe、K和Ca）可以使用激光雷达（激光雷达）从地面观测到，为研究空间边缘过渡区的物理和化学提供了重要工具。一个长期存在的谜团是为什么钙层严重耗尽，包含不到预期密度的1%。拟议的项目将首先研究控制上层中间层钙化学的反应，然后建立一个模型，其中包括对流星消融过程的详细描述，以此解决这一问题。该模型将进行测试，对激光雷达测量的钙原子和钙离子，从两个天文台在低纬度和中纬度。该模型和激光雷达数据还将用于研究零星E层的化学性质，E层是金属离子和电子的集中层，对无线电传播有显着影响。一个特别的目标是预测这些层的寿命。

项目成果

A chemical model of meteoric ablation

流星烧蚀的化学模型

• DOI: 10.5194/acp-8-7015-2008
• 发表时间: 2008
• 期刊: Atmospheric Chemistry and Physics
• 影响因子: 6.3
• 作者: Vondrak T