An apparatus for modification of the atmospheric humidity profile via creating updrafts of moistened air is provided. The apparatus is based on a capacitor of a Van der Graaf generator which, with the aid of air ionizers comprising a source of alpha particles, produces a unipolar atmospheric electric current of a magnitude sufficient to achieve selective moisture transport. Operating such an apparatus augments or creates a moisture updraft, which may lead to the formation of new clouds and/or an increase in supersaturation in existing clouds, thus enhancing the development of precipitation and/or facilitating the inflow of the evaporated moisture from a water reservoir inland.