Which temperature?

Hi There
I am keeping on tuning my huge quad octo and so far I’m pretty happy with the results.
I was wondering if someone could chime in and shed some light on how to interpreter the temperatures logs as they keep being quite erratic and I am not sure it could be a sign of a bad baro on my pixhawk.

Which temperature the logs BARO IMU1 and IMU2 refers to? I am guessing is the external temperature and displayed in Fahrenheit.

Variations, as in the log ( dropbox.com/sh/pux0flv47x21 … P1PHa?dl=0 ), are over 10 degrees during the flight, logs from other flights show sometime a pretty stable temperature, it seems to me this is totally random. Also temperatures are never even close to the real external temperatures as this should be over 30 degrees celsius in this african summer!!
Any help or link to resources is much appreciated.
Happy flights