太阳旋转对火星和地球热层的影响
Jeffrey M Forbes1, Sean Bruinsma, Frank G Lemoine
1Department of Aerospace Engineering Sciences, University of Colorado, Boulder, CO 80309, USA. forbes@colorado.edu
Science (New York, N.Y.)
|June 3, 2006
概括
地球 地球 地球 地球 地球 地球
科学领域:
- 行星科学 行星科学
- 大气物理学 大气物理学
- 太阳与地球的关系
背景情况:
- 热层是一个重要的大气层,受到太阳活动的影响.
- 了解热层对太阳流量变化的反应是大气建模的关键.
- 以前的研究表明,行星的太阳反应不同.
研究的目的:
- 为了比较地球和火星对太阳流变化的热层温度反应.
- 为验证和改进比较热层模拟提供观测数据.
- 调查太阳旋转驱动的流量变化在行星大气热平衡中的作用.
主要方法:
- 当代测量地球和火星上的热层反应.
- 使用10.7厘米的无线电流量作为极端紫外线 (EUV) 流量的代理.
- 分析温度变化,以应对典型的20个单位的太阳流量变化.
主要成果:
- 地球的热层显示,每20个单位的太阳流量变化,温度增加42.0±8.0K.
- 火星的热层表现出较小的反应,温度增加了19.2 ± 3.6 K.
- 金星数据表明3.6 ± 0.6 K的反应甚至更小.
结论:
- 地球的热层对太阳流变化的反应是火星的两倍.
- 这些发现为比较行星热层模型提供了关键的观测约束.
- 结果可能有助于解决行星热平衡的不确定性,特别是关于二氧化碳冷却.
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