Discrepancy between sp parameter in surface analysis ans lnsp parameter in model level analysis

In my analysis files, I’ve noticed that the sp surface pressure parameter values do not match those obtained from the lnsp (natural logarithm of surface pressure) in model level data.

Is this expected or am I missing something? Based on the wording of the documentation, both parameters refer to the same physical quantity.

Here is the description for sp and lnsp.