Different GMST values when only the start year is different in the F1850C5 experiment.

[sysong]

Hello,

I integrated the F1850C5 component set 12 times with only different in the start year. (only 1 month for JAN)
However, each experiment shows different GMST values as follows:

start year GMST
0001-01 12.0679
0002-01 12.1367
0003-01 12.1363
0004-01 12.1363
0005-01 12.1363
...
0010-01 12.1774
0011-01 12.1774
0012-01 12.14041

-> How can we interpret these results?
Does the initial files for each experiment have different values with very small perturbations?

Thank you for helping!