fix three bugs: one in canopy, one in run fluxnet, one in fluxnet data (#1310)

Author: kmdeck

experiments/integrated/fluxnet/ozark_pft.jl

@@ -58,7 +58,6 @@ site_ID_val = FluxnetSimulations.replace_hyphen(site_ID)
     soil_α_NIR,
     Ω,
     χl,
-    G_Function,
     α_PAR_leaf,
     λ_γ_PAR,
     τ_PAR_leaf,

experiments/integrated/fluxnet/ozark_soilsnow.jl

@@ -55,7 +55,6 @@ site_ID_val = FluxnetSimulations.replace_hyphen(site_ID)
     soil_α_NIR,
     Ω,
     χl,
-    G_Function,
     α_PAR_leaf,
     λ_γ_PAR,
     τ_PAR_leaf,

experiments/integrated/fluxnet/run_fluxnet.jl

@@ -58,7 +58,6 @@ site_ID_val = FluxnetSimulations.replace_hyphen(site_ID)
     soil_α_NIR,
     Ω,
     χl,
-    G_Function,
     α_PAR_leaf,
     λ_γ_PAR,
     τ_PAR_leaf,

ext/fluxnet_simulations/data_processing.jl

@@ -186,8 +186,8 @@ function FluxnetSimulations.get_comparison_data(
         v = data[:, idx]
         missing_mask = var_missing.(v; val)
         not_missing_mask = .~missing_mask
-        n_missing = sum(not_missing_mask)
-        if n_missing <= length(v) # some data are present
+        n_missing = sum(missing_mask)
+        if n_missing < length(v) # some data are present
             v[missing_mask] .= sum(v[not_missing_mask]) / sum(not_missing_mask)
             return (; Symbol(climaland_shortname) => preprocess_func.(v))
         else

src/standalone/Vegetation/canopy_parameterizations.jl

@@ -59,13 +59,16 @@ end
 
 Returns the leaf angle distribution value for CLM G function as a function of the
 cosine of the solar zenith angle and the leaf orientation index.
-See section 3.1 of https://www2.cesm.ucar.edu/models/cesm2/land/CLM50_Tech_Note.pdf
+See section 3.1 of https://www2.cesm.ucar.edu/models/cesm2/land/CLM50_Tech_Note.pdf.
+
+Note that the zenith angle is defined ∈ [0,2π), so to prevent a negative value
+of G when the sun is below the horizon, we clip cosθs >= 0.
 """
 function compute_G(G::CLMGFunction, cosθs::FT) where {FT}
     χl = G.χl
     ϕ1 = 0.5 - 0.633 * χl - 0.33 * χl^2
     ϕ2 = 0.877 * (1 - 2 * ϕ1)
-    return FT(ϕ1 + ϕ2 * cosθs)
+    return FT(ϕ1 + ϕ2 * max(cosθs, 0))
 end
 
 """