Bar (unit) mb (rather than the proper mbar) to denote the millibar. Between 1793 and 1795, the word bar was used for a unit of weight in an early version of the metric system. Atmospheric air pressure is often given in millibars, where standard atmospheric pressure at sea level is defined as 1013.25 mbar, 101.325 kPa, 1.01325 bar, which is about . Despite the millibar not being an SI unit, meteorologists and weather reporters worldwide have long measured air pressure in millibars as the values are convenient. After the advent of SI units, some meteorologists began using hectopascals (symbol hPa) which are
ALCO PA display in the museum. Unit DH-17 (former D&H #17) was painted in the classic Southern Pacific Daylight colors, but as of February 2010 had been painted over in primer. Algoma Central 78 is the former Denver and Rio Grande PB-1 6002. It was converted to a steam generator car in October 1965. It gained Blomberg B trucks in 1980. It was sold to Ansco in late 1987 for service on the Ski Train. It was sold again in 2007 to the Algoma Central. ALCO PA ALCO PA refers to a family of A1A-A1A diesel locomotives built to haul passenger trains