Abstract
The results of 17 northern California soundings of humidity up to 25–30 km, generally a month apart, utilizing a highly sophisticated alpha-radiation hygrometer and associated balloon sounding equipment are described. The stratosphere was never found to be near saturation as has been suggested by some investigators, nor was it as dry and completely devoid of variability as is indicated by the most accepted circulation theory. A very dry layer was found above the tropopause, followed by a slight increase in humidity up to an average altitude of about 25 km. Above this level a general decrease in water vapor with altitude was deduced. Variability in this region of the lower stratosphere approached a factor of 10. Spasmodic transfer of water vapor upward through the tropopause is suggested and speculation related thereto provided.