Because warm air can hold more moisture than cool air, the relative humidity will be constant only if the amount of water vapor in the atmosphere increases as the temperature rises.

因为温暖的空气比冷空气能容纳更多的湿气，所以只有当大气中的水蒸气量随着温度的升高而增加时，相对湿度才会保持不变。

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Water vapor in the lower atmosphere can vary in amount from a mere trace in arid regions to about 4% by volume in moist areas.

大气低层的水汽量在干燥地区（量）甚微，而在潮湿地区按体积占4%左右。

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Absolute humidity is a measurement of the total amount of water vapor in the air at a given temperature.

绝对湿度是指在给定温度的情况下，空气中所含的水蒸气重量的绝对值。

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The gas is then fed into a stack of solid oxide fuel cells, where a chemical reaction between hydrogen and oxygen occurs, producing electricity, water vapor and a tiny amount of carbon dioxide.

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Absolute humidity, on the other hand, refers to the actual amount of water vapor in the air regardless of saturation.

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So Feldstein invented a system that pressurizes a small amount of water and pushes it through tiny nozzles, atomizing it into vapor.

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