火星南极冰的升华模型具有火星南极冰的特征
Shane Byrne1, Andrew P Ingersoll
1Division of Geological and Planetary Sciences, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA.
概括
火星的大气层 火星的大气层
科学领域:
- 行星科学 行星科学
- 大气科学 大气科学
- 地质地质地质地质地质地
背景情况:
- 火星的大气主要是二氧化碳.
- 以前的研究表明,一个大型的极地二氧化碳储备控制大气组成.
- 极地水库在火星大气调节中的作用受到争议.
研究的目的:
- 挑战目前普遍认为火星上存在大型极地二氧化碳储备的理论.
- 为火星大气中的二氧化碳循环提出一个替代模型.
- 为了研究火星南极帽的组成和动态.
主要方法:
- 利用火星南极帽上圆形低谷的计算建模.
- 分析来自火星奥德赛任务的热红外数据.
- 研究二氧化碳冰和水冰层之间的相互作用.
主要成果:
- 极地二氧化碳储备可能比以前估计的要小得多.
- 大约8米厚的二氧化碳冰层正在被侵蚀.
- 地下水冰正在被二氧化碳冰的升温暴露.
- 这个过程与观察到的热红外线信号一致.
结论:
- 小的极地水库不能作为火星大气的长期缓冲.
- 观察到的特征表明二氧化碳冰蚀刻的动态过程.
- 火星大气中二氧化碳的调节机制可能不同于之前的假设.
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