Long-term changes in atmospheric electrical parameters observed at Nagycenk (Hungary) and the UK observatories at Eskdalemuir and Kew

Abstract

Abstract. The Nagycenk Geophysical Observatory in Hungary (47 • 38 N, 16 • 43 E) has made continuous measurements of the vertical atmospheric electric Potential Gradient (PG) since 1962. Global signals have previously been identified in the Nagycenk PG data. A long-term decrease has been discovered in the PG measured at the Eskdalemuir Observatory, Scotland (55 • 19 N, 3 • 12 W), suggesting that this represents a global change in the atmospheric electricity related to a decline in cosmic rays. A 40% decline in PG is shown here to have occurred at Nagycenk between 1962 and 2001, also consistent with changes in the air-Earth current measured at Kew (51 • 28 N, 0 • 19 W), London, 1966London, -1978 Comparison of the long-term PG measurements at both Eskdalemuir and Nagycenk gives further evidence to support the hypothesis of a global atmospheric electrical decline from the early twentieth century to the present time, as it is shown that local effects at Nagycenk are unlikely to have dominated the changes there.

The Global Atmospheric Electrical Circuit and Climate

“…A similar behaviour has been found in data from the UK and Hungary (Märcz and Harrison, 2003), and in data from the Bavarian Alps (Harrison, 2004b). Since these studies consider the shape of the Carnegie curve, rather than the absolute magnitude, these observations could suggest that either the DC global circuit is at its strongest during the winter, or short-term changes are particularly small, or a combination of the two factors.…”

The Global Circuit Intensity: Its Measurement and Variation over the Last 50 Years

“…From a few years after the end of nuclear testing until the most recent measurements in 2004, Vi values have remained essentially constant within ±10% of the mean. This finding contradicts reports that over the last 39 years the global circuit intensity has decreased by 44% (Marcz and Harrison 2003).…”

“…The Hungarian data show a 44% decrease in electric field in 39 years, that is, 113% per century. These data were obtained near a group of growing trees close to the measuring site (Marcz and Harrison 2003). The reported values, starting at 66 V nr 1 in 1962 and ending at 37 V nr 1 in 2001 are 1/2 to 1/3 of the typical fair-weather electric field intensity of about 130 V nr 1 (Chalmers 1967, p. 202;Israel 1973, p. 338).…”

“…Recent reports based on ground-level electric field data in England (Harrison 2002) and Hungary (Marcz and Harrison 2003) conclude that the global circuit intensity has decreased by about half or more during the twentieth century. This conclusion is questionable since these measurements would have been influenced by the large air pollution decreases in England during this period (Williams 2003).…”

Hungarian national report on IAGA 2007–2010

“…Earlier investigations have shown different time variations in the atmospheric electric potential gradient (PG). Based on data observed at Nagycenk and at two stations in the UK (Eskdalemuir, Lerwick) a long-term decrease has been revealed in the PG (Märcz and Harrison 2003). Previously, Nagycenk PG data have been investigated (Märcz 1997) with the aim at detection of responses in the surface PG to extraterrestrial changes.…”