Light shielding device and light shielding method

A light shielding method using, in order to change weather, a light shielding device having a shielding member configured to shield a spectrum of sunlight and a buoyant force imparting unit configured to impart buoyant force to the shielding member to put the shielding member into a floating state,

• the shielding member being configured by a film material,
• the floating state being a situation in which the shielding member and an object that is engaged with the shielding member are in a non-contact state with a surface of the ground,
• the buoyant force imparting unit including a plurality of buoyant members each filled with gas lighter than air,
• the plurality of buoyant members
• being provided in a distributed manner, and constituting a part or all of a main body of the light shielding device, and
• including gas adjusting unit configured to individually adjust an amount of the gas lighter than the air,
• the method comprising a step of imparting the buoyant force to the shielding member while balancing between the buoyant force of the plurality of the buoyant members provided in the distributed manner and own weight due to gravity of the main body of the light shielding device at corresponding portions by individually adjusting the amount of the gas lighter than the air filled in each buoyant member with the gas adjusting unit.