I made a GIF image file (not Geophysics Interferometer!!!) to show a seasonal change of the long term spectrum as I posted 9386.
This GIF is made of 8 pictures which are divided from this long term spectrum.
(Data is in here; https://github.com/MiyoKouseki/kagra-gif/issues/108)

According to this GIF, seismic motion is noisy in winter season, while It is quite in summer.

I could say that we have to prepare the inertial damping on the pre-isolator stage for joinging O3 in winter season.
Or, because inertial sensors of KAGRA are too noisy to control that, we have to prepare the global seismic
damping using the GIF strainmeter which is posted here (, although only X-arm) .