Is the pressure what makes Siberia so warm?

Of course...and that must be why people wearing scuba tanks are always under water. At 3000 psi those things must surely be scalding hot to the touch.

Atmospheric pressure has always been variable. That's what makes our climate variable and "shifty". It is true that there has been a "human fingerprint" found on temperature and atmospheric pressure, but it is very very small. The measurement over the last 68 years is less than 0.5% (less than 5mb) and works out to be an overall "wash". Pressure at the Poles has been measured over the last 68 years and is lower, while measurements around the Tropics are a bit higher.

Overall atmospheric pressure at the Poles changes with the ozone changes, but those changes have been found to be mostly due to NATURAL occurrences.

Bottom line :

The overall atmosphere has temperature variability and pressure variability, which has almost nothing to do with anthropogenic influences. Changes of less than 5mb (0.5%) over 6 to 7 decades is well within NATURAL VARIABILITY and the "human fingerprint" on those 0.5% (less than 5mb) changes are very difficult to identify with any scientific certainty. They assume those changes are mostly caused from anthropogenic sources. There's still no absolute certainty to the scientific method of blaming humans for the changes. The human footprint on the overall climate is miniscule.