Effect of solar flares on lower tropospheric temperature and pressure

The effect of solar flares on lower tropospheric (i.e. ground surface, 850, 700 and 500 mbar levels) temperature and pressure (i.e. dynamic height of constant pressure surface) has been studied. The data of 81 flares for the period 1957-59 at a few selected stations in India have been analyzed. The analysis shows that the effect of solar flare occurs within a 24-hr period, while the influence starts receding after 48 hr. The change in the magnitude of the solar flare influence is observed to decrease with decrease of altitude. The effect on pressure is more pronounced compared to that on temperature. (author)