“How is entropy applicable to a non-closed system?:
There IS no non-closed system since we have only one universe. The universe is a system and it is in indeed closed...
Then quantify the enthalpy in your so-called closed system. Jeez, I hate it when people who can't even balance their own checkbooks challenge the calulus of evolution.
The earth is not a closed system.
I’d suggest a review of entropy is in order... The 2nd law of thermodynamics is completely consistent with the theory of evolution, as well as the theory of aggregation of matter into planets and stars.
Total energy in the system is decreasing, as the energy contained in accelerated mass is spent in aggregation of planets and stars, and further decreased by thermal means (friction, fission, and fusion).
That said, local entropy can reverse if the entire system is decreasing, due to the expenditure of large amounts of energy (see the aforementioned creation of stars).