Bar is a unit of which quantity?

Bjerknes is credited with developing the foundation for dynamic meteorology, which uses mathematical equations to describe and predict weather patterns. He proposed a "physical weather prediction" approach based on mathematical formulas and enough information about the atmosphere. He was ahead of his time.

Dog Lady, the gauge that has the word pressure on it.

1 bar = 1000 hectopascals

Once again, have to go with the picture