Convert one bar to atmospheres

Explanation

To convert one bar to atmospheres all we need is to know the conversion factor and we are done. Luckily, we can compute that factor using the units' definitions below.

We find that one bar is approximately equal to 0.9869 atmospheres.

Formula

1 bar ≈ 0.9869 atm

barsbar

dimension	pressure
symbol	bar

The bar (bar) is a metric unit of pressure not part of the SI.

The unit is most prominently used in meteorology to express atmospheric air pressure with values generally in millibars.

One bar is roughly equal to the average atmospheric pressure at sea level on Earth.

Definition of the bar

One bar is equal to 100000 pascals.

The International System of Units 8^th edition p. 127

Equivalences

One bar is equivalent to:

Some Facts

The atmospheric pressure at the surface of Venus is 92 bars, at this pressure the boiling point of water is more than 300 °C (or 572 ° F). Teatime must be quite peculiar on Venus.

atmospheresatm

dimension	pressure
symbol	atm

The standard atmosphere (atm) is a unit of pressure.

It is approximately equal to the atmospheric pressure on Earth at sea level.

Definition of the atmosphere

One standard atmosphere is equal to 101325 Pa.

10^th CGPM (1954) p. 80

History

The standard atmosphere is used during the 9^th CGPM in the definition of the international temperature scale with the value of 1013250 dynes per square centimetre. That definition is reiterated during the 10^th CGPM with the mention "for all use" and the equivalence of 101325 newtons per square meter is added (and as you all know, 1 pascal is equivalent to 1 newton per square meter).

Equivalences

One standard atmosphere is equivalent to:

Some Facts

For every 10 meters you go down under water, the pressure increases by one atm.
Venus's surface atmospheric pressure is more than 90 atm.
The atmospheric pressure at the top of Mount Everest is approximately 0.33 atm.

millibar	mbar	0.001
centibar	cbar	0.01
decibar	dbar	0.1
bar	bar	1
decabar	dabar	10
hectobar	hbar	100
kilobar	kbar	1000
megabar	Mbar	1 000 000