Multiple empirical studies analyzing cloud ceilings, low-level cloud bases, and boundary layer heights across diverse geographic regions confirm that there are observable seasonal differences in the average cloud floor.
The claim asserts that there is a seasonal difference in the average cloud floor. Paper 0, Paper 5, and Paper 8 all directly examine seasonal variations or trends in cloud ceiling heights, low-level cloud base heights (CBH), or planetary boundary layer heights across different regions (California, Poland, and India, respectively), consistently demonstrating empirical differences across seasons. Therefore, the claim is supported by the retrieved literature.