1bar

1bar refers to a unit of pressure. It is defined as exactly 100,000 pascals. This unit is commonly used in meteorology, where it is roughly equivalent to atmospheric pressure at sea level. The term "bar" itself originates from the Greek word "baros," meaning weight.

While 1 bar is a convenient unit, it is not an SI base unit. The SI unit of pressure is the pascal (Pa), which is defined as one newton per square meter. Since 1 bar is equal to 100,000 pascals, it is often expressed in scientific contexts as 100 kPa.

In practical applications, 1 bar is a useful approximation for atmospheric pressure. Standard atmospheric pressure at sea level is defined as 101,325 pascals, making 1 bar very close. This similarity has led to its widespread adoption in fields like weather forecasting and aviation. Other related units of pressure include the millibar (mbar), where 1 bar equals 1000 mbar, and the hectobar (hbar), where 1 hbar equals 100 bar. The millibar is particularly prevalent in meteorological reports.