与此同时，我们还统计了1957与1958年高纬度区31个地磁台在平静时每天的平均日变化。

We have also calculated the mean daily variation of K index of 31 stations of high latitude during the relative magnetic quiet period of year 1957 and 1958.

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虽然日期的变化最大的雪水，一年到现在的平均融雪到来之前两周半比1961年10月30日，当峰融雪首次测量。

While the date of maximum snowmelt varies from year to year, peak snowmelt now arrives an average of two-and-a-half weeks earlier than it did in 1961, when peak snowmelt was first measured.

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平均雾日较多的宜君、石泉和西安有较明显的年变化，大致有6年和8年的准周期。

The mean foggy days of Yijun, Shiquan and xi 'an exist obvious interannual change, about quasi-period of 6, 8 years.

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