Long-term measurements of the vertical electrical potential gradient in the atmospheric surface layers
A long series of measurements of the surface electric potential gradient have been made since 1962 in Sweden. A modifed atmospheric electrical station of the Kasemir–Dolezalek construction is used. Other electric and meteorological parameters are also measured. The effect of local air pollution appears essentially less than at other evaluated continental atmospheric electric stations. Previous studies of the diurnal variations of the electric potential gradient at Marsta show that they are well correlated with the Carnegie curve during winter and ill correlated during summer. Our long-term measurements during the years 1962—2002 show small changes in the long-term variation of the vertical electric potential gradient in winter or during the year. Other previous long-term measurements in Europe, however, show a pronounced long-term decrease in the vertical electric potential gradient. The differences in the observations can be due to changes in the surroundings of the observation sites. Even local changes in the concentration of air pollution can explain the differences. Balloon measurements of the ionospheric potential from 50 years measurements at different places over the globe also show no pronounced long-term trend.
Sven Israelsson
Department of Earth Sciences, Division of Meteorology, University of Uppsala,Villavágen 16, Uppsala, SE-75236, Sweden
国际会议
第13届国际大气电学会议(The 13th International Conference on Atmospheric Electricity)
北京
英文
2007-08-13（万方平台首次上网日期，不代表论文的发表时间）