What device measures humidity in the atmosphere?

A hygrometer is the device specifically designed to measure humidity in the atmosphere. It works by detecting the moisture content in the air and can use various methods to do so, including the use of a dew point, wet and dry bulb temperatures, or electrical resistance. Different types of hygrometers exist, such as psychrometers and digital hygrometers, each providing valuable information about atmospheric moisture.

In contrast, a barometer measures atmospheric pressure, which is important for weather predictions but does not directly provide information about humidity. An anemometer is used to measure wind speed, offering insights into wind conditions rather than moisture levels. A thermometer measures temperature, which can influence humidity but does not assess it directly. Thus, the hygrometer is uniquely suited for measuring humidity, making it the accurate choice.