Abstract The response of the atmosphere to solar irradiance and geomagnetic activity is analyzed in experiments with the Whole Atmosphere Community Climate Model (WACCM) under idealized forcings. Four experiments are carried out combining high (H) and low (L) solar radiative forcing with high (7) and low (3) geomagnetic activity: H7 (with high radiative forcing and high geomagnetic activity), H3, (high/low), L7 (low/high), and L3 (low/low). The comparison between these experiment is used to assess the effects of solar radiative forcing and geomagnetic activity mainly on the stratosphere. A two-step Monte Carlo-based statistical test, which defines an impact score, is used to assess statistically significant impacts on regional scales, on pressure levels, for a few key model variables, like NOx, ozone, and temperature. Under low solar forcing (L7/L3), a statistically significant relationship between geomagnetic activity and NOx is found in both hemispheres and for all seasons. An equally strong relationship is lacking for ozone and temperature when analyzing these fields on isobaric levels. A statistically significant impact on stratospheric ozone is only seen in austral winter and spring. However, vertical cross sections show statistically significant impact on temperature and ozone mainly in the southern hemisphere (SH) during austral winter and the following spring. Significant and persistent signals in both SH NOx and ozone concentrations are only produced when the effect of high solar forcing is added to high geomagnetic activity (H7). In this case, statistically significant differences are also found for mesospheric temperatures, ozone and NOx. This latter result appears also under low geomagnetic activity as a result of solar forcing alone, suggesting that solar irradiance significantly affects NOx, ozone and stratospheric temperatures and, in some seasons, even tropospheric temperature. In summary, geomagnetic activity primarily affects NOx and ozone concentrations in the SH. Solar maximum conditions can reduce the amount of NOx in the stratosphere because of higher ozone production. Thus, we conclude that correlations between changes in solar irradiance and geomagnetic activity are important with respect to their effects on the atmosphere. In particular, geomagnetic activity can modulate atmospheric ozone concentrations and other associated stratospheric and tropospheric variables under conditions of high solar activity.

中文翻译：

---

WACCM 模拟中太阳辐照度和地磁活动对极地 NOx、臭氧和温度的影响

摘要 大气对太阳辐照度和地磁活动的响应在理想化强迫下的全大气群落气候模式（WACCM）实验中进行了分析。结合高 (H) 和低 (L) 太阳辐射强迫与高 (7) 和低 (3) 地磁活动进行了四个实验：H7（具有高辐射强迫和高地磁活动）、H3、（高/低） 、L7（低/高）和 L3（低/低）。这些实验之间的比较主要用于评估太阳辐射强迫和地磁活动对平流层的影响。基于蒙特卡罗的两步统计测试定义了影响分数，用于评估对区域尺度、压力水平以及一些关键模型变量（如 NOx、臭氧和温度）的统计显着影响。在低太阳强迫 (L7/L3) 下，在两个半球和所有季节都发现地磁活动与 NOx 之间存在统计学上显着的关系。在等压水平上分析这些场时，臭氧和温度缺乏同样强烈的关系。对平流层臭氧的统计显着影响仅在南方冬季和春季可见。然而，垂直横截面显示出对温度和臭氧的统计显着影响，主要是在南半球（SH）的南半球冬季和次年春季。SH NOx 和臭氧浓度的显着和持久信号仅在高太阳强迫效应与高地磁活动 (H7) 相加时才会产生。在这种情况下，还发现了中间层温度、臭氧和 NOx 的统计显着差异。后一种结果也出现在低地磁活动的情况下，因为单独的太阳强迫，这表明太阳辐照度显着影响 NOx、臭氧和平流层温度，在某些季节，甚至对流层温度。总之，地磁活动主要影响 SH 中的 NOx 和臭氧浓度。由于臭氧产量较高，太阳极大值条件可以减少平流层中的氮氧化物含量。因此，我们得出结论，太阳辐照度变化与地磁活动之间的相关性对于它们对大气的影响很重要。特别是，地磁活动可以在高太阳活动条件下调节大气臭氧浓度和其他相关的平流层和对流层变量。