抄録
The spiral troughs on Mars' polar ice caps are considered as cyclic steps formed on ice due to katabatic wind. Katabatic wind is a type of density current which flows downward pulled by gravity because of the denser air cooled by the ice floor. Due to the spatial non-uniformity of solidification of water vapor included in the air onto the ice floor, and sublimation of ice into the air, the boundary waves are formed on the ice floor. We performed laboratory experiments simulating the condition that katabatic wind blows on ice. Boundary waves were formed on the ice in the case that there was a large difference in temperature between the room air and the bottom of the ice.
