Miscellaneous issues - state variable saving and variable initialization

[yixinmao]

There are two remaining things for closed issue #479 :

• We are saving two flux variables (energy->LongUnderOut and energy->snow_flux) to state file for exact restart purpose - this is not ideal. Specifically:

  • energy->LongUnderOut (this is a flux variable whose old value from the last time step is used before being updated in the current time step)

  This variable is calculated in "generate_default_states()" when no initial state is specified (so when there is no initial state, LongUnderOut would be calculated first; but when there is an initial state, LongUnderOut remains zero before the first time step calculation). This variable is currently saved to state file to ensure exact restart [PR #507]. TODO: this is a temporary solution; a better way of handling this flux variable needs to be done (potential solutions: 1) modifying the calculation in vic_run so that the flux variable is always computed before used; 2) computing the flux variable from state variables before vic_run)

  • energy->snow_flux (this is a flux variable which has the same problem, and is also temporarily saved to state file [PR #507])
• Local variables used before initializing (these do not affect restart, but better to be fixed also):
  • In surface_fluxes(), the local variable ShortUnderIn is used before initialized
  • In func_surf_energy_bal(), line 662-663, variable fusion is used; but fusion is only initialized if FROZEN_SOIL=TRUE

[bartnijssen]

@yixinmao : Please assign labels and a milestone

[bartnijssen]

Closed and continued as two separate issues: #592 and #593