青海德令哈地区近400年来的降水量变化与太阳活动

PRECIPITATION VARIATION IN DELINGHA, QINGHAI AND SOLAR ACTIVITY OVER THE LAST 400 YEARS

使用多种数学统计方法分析了德令哈地区降水量变化与太阳活动之间的关系,发现近 400年来降水量的长期变化与太阳黑子周期长度(SCL)和太阳黑子周期上升支长度之间存在着较好的反相关关系,当SCL偏短、太阳黑子周期上升支长度偏短时,太阳活动偏强,德令哈地区降水量偏多,反之偏少。功率谱和小波分析发现降水量序列中存在着与太阳活动的多种周期相一致的周期,对降水量与太阳活动在不同时间尺度上周期变化之间的关系进行了详细分析。交叉小波分析发现太阳活动主要在百年左右尺度的周期变化上影响德令哈地区降水量的长期变化,太阳活动周期变化的信号越强,对降水量变化的影响越大。文章最后对太阳活动影响德令哈地区降水量变化的可能机制进行了探讨。

Using statistic methods, we examine the relationship between precipitation variation in Delingha, Qinghai and solar activities during the last 400 years. The precipitation of Delingha is negatively correlated to the sunspot cycle length (SCL) and the sunspot cycle rising phase length. When the SCL and the sunspot cycle rising phase length are shorter, the solar activity tends to be stronger, and there is more precipitation in Delingha. Using the power spectral analysis and the wavelet analysis, we find that the main cycles of the precipitation of Delingha are similar to the cycles of solar activity over the last 400 years. Detail analysis of the cycles was carried out to find the relationship between precipitation and solar activity at different time scales. We then make the cross-wavelet analysis and find that the solar activity can effect the long-term variation of precipitation mainly in the century-scale. When the cycle of solar activity is stronger, the affect of solar activity on the precipitation is greater. Our analysis suggests that the solar activity probably plays an important role in influencing the precipitation of Delingha over the past 400 years. The possible physical mechanism of such influence is discussed. Further studies in the future may help us better understand the mechanism that links solar activity with precipitation.