Abstract
Fogs are thought to play an important role in deposition of acidic constituents in the atmosphere and also to be closely related to the decline of forests. We applied the polymeric water absorbent of a commercial diaper to the measurement of the deposition flux of fog water, for the first time. The absorbent was molded into a disk of 13 mm in diameter and 1mm in thickness, and characteristics of the disk, such as water vapor absorptivity and water retention ability, were studied in detail. Then we exposed the disk to the artificial fog in a cloud experiment facility, a large-scale vertical shaft (a long vertical passage or space in a mine) of Kamaishi Mine in Iwate Prefecture, in which a steady fog suitable for methodological studies on fogs was formed. The disks were hung on branches of a model pine tree, and the flux was determined from the increase in weight, the surface area of the disk and the exposure time to the fog. It was found through the present new method that the deposition flux was almost independent of wind directions, being 46 ∼ 65 g/m2/h. These values fell in the range of past data for tree leaves reported in literature.
