Minimilämpömittari

Minimilämpömittari, also known as a minimum thermometer, is an instrument used to record the lowest temperature reached over a specified period. It is commonly employed in meteorology to track overnight low temperatures. The design of a minimilämpömittari typically involves a mercury or alcohol-filled glass tube with a constriction in the bore. As the temperature drops, the liquid contracts and is pulled back into the bulb. The constriction prevents the liquid from retracting further into the bulb as the temperature rises, leaving an indicator at the lowest point reached. This indicator can be a small dumbbell-shaped bead within the liquid column or a separate marker. To reset the minimilämpömittari, the instrument is usually tilted or shaken to push the indicator back down to the level of the liquid. These thermometers are often housed in a Stevenson screen to protect them from direct sunlight and precipitation, ensuring accurate readings of ambient air temperature. They are essential for understanding diurnal temperature variations and are a standard component of weather stations.