Long-term trends in geomagnetic daily variation

被引：24

作者：

Macmillan, Susan ^{[1
]}

Droujinina, Anna ^{[1
]}

机构：

[1] British Geol Survey, Edinburgh EH9 1LS, Midlothian, Scotland

来源：

EARTH PLANETS AND SPACE | 2007年 / 59卷 / 05期

关键词：

geomagnetism; daily variations;

D O I：

10.1186/BF03352699

中图分类号：

P [天文学、地球科学];

学科分类号：

07 ;

摘要：

Long-term changes in the magnetic environment of the Earth are of interest to those studying space weather and climate change, particularly in the upper atmosphere. In this paper we examine long-term changes in daily variation as derived from hourly mean values from 14 geomagnetic observatories around the world. Their time series date back to the beginning of the 20th century. We find that there are similar features in all the records, with peaks in the amplitudes of the daily variation occurring in the 1950s and 1980s, and a small upward trend of 1.3 nT/century corresponding to an increase of over 10%. The extrema coincide with those seen in solar irradiance proxy data, in particular the F10.7 flux density dataset which starts in 1947.

引用

页码：391 / 395

页数：5

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