canopy.c-all_sided-proj_LAI

CPTBTPTP-bit commented 5 years ago

Hello:

What is written in the comment is to multiply ALL_SIDED , but it is actually multiplied by PROJ_LAI.  canopy.c

   /* Leaf conductance to sensible heat, per unit all-sided LAI */
gl_sh = gl_bl;                                                                                                              

/* Canopy conductance to evaporated water vapor */
gc_e_wv = gl_e_wv * proj_lai;                                                                                               

/* Canopy conductane to sensible heat */
gc_sh = gl_sh * proj_lai;

Thanks

bpbond commented 5 years ago

It does look like this comment is wrong, but @thorntonpe (the original author 20 years ago...) doesn't make many mistakes, so pinging him to check if we're missing something.

CPTBTPTP-bit commented 5 years ago

Thank you very much for your reply!

thorntonpe commented 5 years ago

@WYPZL @bpbond Thanks for your question - it has provided an opportunity for me to revisit both the BGC4.2 code, and my thesis! The comment about all-sided LAI in canopy_et.c is erroneous - it should say projected LAI. The code itself is correct. This comment is a remnant of some of the original Biome-BGC code, developed with conifers as the primary plant type of interest, at a time when physiological ecologists working with conifers tended to use all-sided LAI for calculations. There is still a conversion between projected and all-sided LAI carried in the code (radtrans.c), but I think the epv->all_lai variable may not be used for anything other than diagnostic output.

CPTBTPTP-bit commented 5 years ago

@thorntonpe Thank you for your reply! Your answer solved my doubts.

bpbond / Biome-BGC

canopy.c-all_sided-proj_LAI #3