Relationship between annual variations in the rate of change of magnetic intensity and those of surface air temperature.

Abstract

Magnetic intensity and temperature data from 29 pairs of magnetic observatories and weather stations in the Northern Hemisphere were compared. Of these, 27 pairs lag correlate. The study covers mainly the period from 1935 to 1975. Annual surface air temperatures were used and both annual absolute values and rate of change values of horizontal component (H) and total intensity component (F) were plotted. Absolute values of H and F when plotted did not correlate with the temperature curves. Twenty-five curves of variations in the rate of change of H lag correlate with paired temperature curves. The 25 curves of variations in the rate of change of F based on data from the same observatories do not correlate with the temperature changes at the paired weather stations. Two curves of the variations in the rate of change of F based on data from two magnetic observatories lag correlate with the temperature records from nearby weather stations. No correlation was found between the records from 2 magnetic observatories and paired weather stations. The lag in temperature trends against magnetic variation ranges from 1 to 3 years. The correlation is inverse; that is, increase in the rate of change of magnetism is followed by decrease in temperature and vice versa. Statistically significant correlations between magnetic variations and temperature changes are reported. Neither the temperature curves nor the magnetic curves correlate with the sunspot number curve. We present two mechanisms which may be responsible for a relationship between annual variations in the rate of change of magnetic intensity and those of surface air temperature.

Search for correlation between the annual rate of change of gemagnetic horizontal intensity and surface air temperature at Alibag-Colaba, Bombay.

“…PITTOCK (1978) has critically discussed the weakness of these sun-weather relationships. Now, again, we are unable to confirm the results of WOLLIN et al (1981) in the case of Alibag-Colaba, Bombay, about a possible inverse correlation between the annual H-changes and the air temperature with a lag of 3 years in the temperature data. Our present results are statistically insignificant.…”

“…1 of WOLLIN et al (1981) pertaining to Alibag and Bombay, has revealed certain inaccuracies in the magnetic secular change data plotted for the years 1944 to 1948, as can be compared and seen with Fig. 1 of this paper.…”

“…Figure 1 gives a plot of the rate of change in the annual means of H at Alibag from 1875 to 1977, along with the annual mean surface air temperature values at Colaba, Bombay, plotted with a lag of 3 years from 1878 to 1980. The data studied by WOLLIN et al (1981) are also shown bounded by two vertical lines for the period of 1937-1967. An examination of the different peaks and valleys in the plots of the two parameters does not readily suggest any meaningful association either for the whole period of 103 years or for the period of 31 years . Nor is there any apparent association between the simulatneous data or the temperature data with a lag of 1 or 2 years.…”

“…Introduction WOLLIN et al (1981) found that the annual rate of change values of magnetic horizontal intensity and the annual mean temperature data ) from 25 out of 29 pairs of magnetic observatories and nearby weather stations in the northern hemisphere, gave a very good inverse correlation , with a lag of 1, 2 or 3 years in the temperature data. They also discussed two mechanisms for the observed relationship.…”

“…In the present investigation, we have re-examined the geomagnetic and temperature data of Alibag and Colaba , Bombay, respectively, for the same 31-year period as studied by WOLLIN et al (1981), as well as for a much longer period of 103 years of the magnetic data . The earlier Colaba magnetic data for the period 1875-1905 were first reduced to the Alibag site and then used.…”