A covering for promoting local rainfall, wherein the covering is for covering a field that can get thermal energy, a space for accommodating air can be formed between the covering and the field, because the air covered by the covering receives the thermal energy and a skin of the covering prevents the air covered by the covering from mixing and convecting with the air outside the covering, a transmission of the thermal energy to the outside of the covering is reduced, making a temperature of air on the inside to be higher than a temperature of air on the outside so as to generate buoyancy, the buoyancy generated by an air temperature difference is utilized to lift up a liftable portion of the skin within an edge part of the covering to form the space for accommodating air and accumulating the thermal energy in the air in the space, hot air covered by the covering can be released to increase local atmospheric instability and stimulate an occurrence of the local rainfall, the covering at least comprises the skin and an anti-buoyancy apparatus, wherein:
- the skin is at least comprised of a broad thin object capable of substantially preventing the air covered by the covering from mixing and convecting with the air outside the covering and has a strength sufficient to bear an estimated stress caused by a buoyancy of the hot air covered by the covering, the skin covers the field that can get the thermal energy, wherein during a period of time from which air storage starts to the space being filled up with air, an edge part of the skin is substantially maintained at an original height at or close to a surface of the field, meanwhile, a portion of the skin within the edge part can be lifted up away from the surface of the field so that the space for accommodating air can be formed between the skin and the surface of the field, a gap between the edge part of the skin and the surface of the field is utilized as an air inlet for the outside air to enter the space;
- the anti-buoyancy apparatus comprises a plurality of anchor members and a plurality of anti-buoyancy pulling members, the anti-buoyancy pulling members are distributed in a scattered arrangement below the liftable portion of the skin within the edge part, the anchor members are fixed to or placed on the field in a scattered manner, an upper end of each of the anti-buoyancy pulling members is connected to a respective portion of the skin and a lower end thereof is connected to the respective anchor member, each of the anti-buoyancy pulling members is for transmitting tensile force between the respective portion of the skin and the respective anchoring member, wherein tensile strength of the anti-buoyancy pulling members can bear the estimated stress caused by the buoyancy of the hot air covered by the covering, the anchoring members are objects that can be connected for being exerted an upper force and are fixed to or placed on a ground or aboveground objects that have sufficient fixing force or gravity for withstanding the buoyancy of the hot air covered by the covering;
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- the covering is adapted to utilize a relatively protruding ground or a relatively protruding existing plant or structure, on the ground within the covered field to lift up a portion of the skin higher than a required height, thereby forming a protruded part of an initiating bulge, so that the air covered by the covering receiving the thermal energy and the skin of the covering reducing the transmission of the thermal energy from the inside to the outside of the covering allow the air temperature difference between two sides of the skin to increase and generate the buoyancy on the protruded part that is greater than gravity of the protruded part and lifts up the protruded part of the skin and sucks the outside air into the space below the covering, the covered air continues receiving the thermal energy thereby the protruded part continues to be lifted up higher and a range of the protruded part becomes wider, meanwhile, the outside air continues to be sucked into the space below the covering, until all of the liftable portion of the skin is lifted up to the heights pre-established and pulled by the plurality of anti-buoyancy pulling members, thereby the space between the covering and the field is completely filled with initial heated air, and then the covered air further receives the thermal energy to further increase a temperature of the covered air, meanwhile water contained in the field below the covering also receives the thermal energy and evaporates into vapor with latent heat and accumulates in the covered air, after a period of reception of the thermal energy, the covered air eventually becomes hot air that is hot and humid, and then by loosening or untying off at least one of the anti-buoyancy pulling members so as to release out the covered air into a lower atmosphere at a proper time, a temperature and humidity of the lower atmosphere is increased, thus a local atmosphere instability is increased and the local rainfall is promoted.