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Monthly variations of lightning activity over typical land and oceanic regions of India were examined using satellite data (OTD) for a 5-year period (1995)(1996)(1997)(1998)(1999). It is noted that the nature of variation between surface air maximum temperature (T max ), thunderstorm days (Th n ), and lightning flash count over ER and WR showed remarkable correspondence and sensitivity with each other on monthly time scale. As we move out of winter season and enter the monsoon season, via pre-monsoon season, the WR undergoes cooling relative to the ER in the range 0.1-1.2 • C. As a result, WR experiences reduction of thunder days and lowering in flash count. This decrease in T max , Th n , and flash count over WR may also be associated with relatively small values of T θw and CAPE in comparison with similar values over ER during the monsoon season. Our observation of associated reduction in Th n and lightning count per 1 • C cooling in surface air maximum temperature suggests reduction of ∼ 3.5 thunderstorms per station and 73 flashes. Comparison of lightning flashes between pairs of coastal, oceanic, arid-zone, hilly, and island stations reveals distinct relationship between climate regime and intensity of lightning activity. We may conclude the results of this study by saying that the overhead lightning activity is a clear reflection of the status of the underlying ground-earth properties. A close and continuous monitoring of lightning activity may be considered as a need of present day scientific studies.

A study of the impact of a total solar eclipse (TSE) on surface atmospheric electricity was made using observations of surface electrical potential gradient, conductivity, and boundary layer parameters recorded during the TSE of February 16, 1980, and on a control day at Raichur. The study showed that with the progressing of the eclipse, as a consequence of inhibited convection, the responses of turbulent mixing in the boundary layer near the ground exhibited diminution and subsequent restoration, respectively. During the next 45 min after the totality, when the surface layer remained stably stratified, the diminution in the potential gradient and the increase in the conductivity was maximum; this was about 60% and 200%, respectively, of their corresponding control day values. This result is in very good agreement with most earlier studies of solar eclipses. The study of the impact of the TSE during 3–4 hours of posteclipse showed significant cooling (∼3°C) of the entire surface air layer and a considerable drop in wind speed over the stretch (1130 km×120 km) of the totality‐occupied land region. This significant and systematic phenomenon was responsible for setting up a land‐sea breezelike circulation, that is, subsidence/downward air motion over the totality‐occupied land region and upward over the noneclipsed land across the totality stretch. This resulted in a considerable aerosol‐induced reduction in conductivity and about 5 to 8 times increase in potential gradient during the 3–4 hours of posteclipse. This response of the atmospheric electricity parameters was unlike that observed on the normal days.

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