The Atmospheric Response to Solar Variability: Simulations with a General Circulation and Chemistry Model for the Entire Atmosphere

该项目的目标是通过使用整个大气层的大气环流和化学模型，提高我们对地球大气层对太阳从热层到地表的可变输入的反应的认识。这将有助于更好地限制观测到的气候趋势的自然和人为原因。这些模拟将涉及太阳变化对不同时间尺度的影响以及与这些时间尺度相关的大气中的耦合现象。在该项目的头两年，计划更详细地研究：1）11年太阳黑子周期的影响及其与平流层和中间层准两年和半年振荡的相互作用，2）27天太阳自转变化的影响及其与大气波的相互作用，3）降水粒子事件的影响和离子在太阳变率响应中的作用。这些问题密切相关。然而，为了了解各个过程，将在项目的第一阶段分别进行研究。模拟将使用MPI气象学的HAMMONIA大气环流和化学模型进行。HAMMONIA是全球三个全面处理整个大气（最大250公里）的动力学，辐射和化学的模型之一。因此，它是研究太阳变化影响的一个非常合适的工具，预计太阳变化在平流层顶（50公里）以上最强，而在平流层顶，悬而未决的问题特别涉及大气层中向上和向下的耦合过程。

The goal of this project is to improve our knowledge on the response of the Earth¿s atmosphere to the variable input of the sun from the thermosphere to the surface by using a general circulation and chemistry model for the entire atmosphere. This will help to better constrain natural and anthropogenic causes of the observed climate trends. The simulations will concern the influence of solar variability on different timescales and the coupling phenomena in the atmosphere related to these timescales. Within the first two years of this project it is planned to study in more detail 1) the influence of the 11-year sun spot cycle and its interactions with the quasi-biennial and semi-annual oscillations in the stratosphere and mesosphere, 2) the influence of the 27-day solar rotational variation and its interactions with atmospheric waves, and 3) the influence of precipitating particle events and the role of ions in the response to solar variability. These issues are strongly linked. However, to understand the individual processes, they will be studied separately in the first phase of the project. Simulations will be performed with the HAMMONIA general circulation and chemistry model of the MPI for Meteorology. HAMMONIA is one of three models worldwide that treat dynamics, radiation and chemistry comprehensively for the entire atmosphere (up to 250 km). Therefore, it is a well suited tool for studying effects of solar variability which are expected to be strongest above the stratopause (50 km) and where the open questions concern in particular up- and downward coupling processes in the atmosphere.