Final answer:
The millibar is a unit of barometric pressure, with one millibar equaling 1×102 Pascals. It is a standard unit used in meteorology, related to other measurements such as mmHg and torr.
Step-by-step explanation:
The millibar is a unit of barometric pressure. It is especially convenient for meteorologists and in the study of atmospheric sciences. One millibar is defined as 1×102 Pascals (Pa). The average atmospheric pressure at sea level on Earth is 1.013×105 Pa, which is equivalent to 1013 millibars (mb) or 1 atmosphere (atm). The conversion of this unit to other pressure measurements is important, as pressure can also be measured in millimeters of mercury (mmHg) or torr, the latter being named after Evangelista Torricelli. One atmosphere is also equivalent to 760 mmHg or 760 torr. Barometers and manometers commonly use these units, as they are standard measurements for atmospheric pressure and are frequently utilized in weather forecasting and blood pressure measurements.