From 59201853581e81cd0293b9330583c5939e26a006 Mon Sep 17 00:00:00 2001
From: Anna Jaruga <ajaruga@caltech.edu>
Date: Tue, 5 Sep 2023 22:23:44 -0700
Subject: [PATCH 1/2] Change supersaturation definition

---
 src/relations.jl  | 18 +++++++++---------
 test/relations.jl | 14 ++++++++++++++
 2 files changed, 23 insertions(+), 9 deletions(-)

diff --git a/src/relations.jl b/src/relations.jl
index 7d4c214c..486e8451 100644
--- a/src/relations.jl
+++ b/src/relations.jl
@@ -1154,34 +1154,34 @@ end
  - `Liquid()`, `Ice()` - liquid or ice phase to dispatch over.
  - `ts` thermodynamic state
 
-Returns supersaturation (qv/qv_sat -1) over water or ice.
+Returns supersaturation (pv/pv_sat -1) over water or ice.
 """
 function supersaturation(
     param_set::APS,
     q::PhasePartition{FT},
     ρ::FT,
     T::FT,
-    ::Liquid,
+    phase::Phase,
 ) where {FT <: Real}
 
-    q_sat::FT = q_vap_saturation_generic(param_set, T, ρ, Liquid())
-    q_vap::FT = vapor_specific_humidity(q)
+    p_v_sat::FT = saturation_vapor_pressure(param_set, T, phase)
+    p_v::FT = vapor_specific_humidity(q) * (ρ * TP.R_v(param_set) * T)
 
-    return q_vap / q_sat - FT(1)
+    return p_v / p_v_sat - FT(1)
 end
 function supersaturation(
     param_set::APS,
     q::PhasePartition{FT},
     ρ::FT,
     T::FT,
-    ::Ice,
+    p_v_sat::FT,
 ) where {FT <: Real}
 
-    q_sat::FT = q_vap_saturation_generic(param_set, T, ρ, Ice())
-    q_vap::FT = vapor_specific_humidity(q)
+    p_v::FT = vapor_specific_humidity(q) * (ρ * TP.R_v(param_set) * T)
 
-    return q_vap / q_sat - FT(1)
+    return p_v / p_v_sat - FT(1)
 end
+
 supersaturation(param_set::APS, ts::ThermodynamicState, phase::Phase) =
     supersaturation(
         param_set,
diff --git a/test/relations.jl b/test/relations.jl
index fe615244..6115e45a 100644
--- a/test/relations.jl
+++ b/test/relations.jl
@@ -278,6 +278,13 @@ end
         _T_triple,
         Liquid(),
     ) ≈ 0.998 * q_tot / ρ_v_triple / ρ - 1
+    @test supersaturation(
+        param_set,
+        PhasePartition(q_tot, 1e-3 * q_tot, 1e-3 * q_tot),
+        ρ,
+        _T_triple,
+        saturation_vapor_pressure(param_set, _T_triple, Liquid()),
+    ) ≈ 0.998 * q_tot / ρ_v_triple / ρ - 1
 
     @test supersaturation(
         param_set,
@@ -286,6 +293,13 @@ end
         _T_triple,
         Ice(),
     ) ≈ 0.998 * q_tot / ρ_v_triple / ρ - 1
+    @test supersaturation(
+        param_set,
+        PhasePartition(q_tot, 1e-3 * q_tot, 1e-3 * q_tot),
+        ρ,
+        _T_triple,
+        saturation_vapor_pressure(param_set, _T_triple, Ice()),
+    ) ≈ 0.998 * q_tot / ρ_v_triple / ρ - 1
 
     # energy functions and inverse (temperature)
     T = FT(300)

From e3477bebc86134c3109aac003aa1f4e559fe0f0c Mon Sep 17 00:00:00 2001
From: Charles Kawczynski <kawczynski.charles@gmail.com>
Date: Wed, 6 Sep 2023 14:43:05 -0700
Subject: [PATCH 2/2] chain calls

---
 src/relations.jl | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/src/relations.jl b/src/relations.jl
index 486e8451..7a1855ad 100644
--- a/src/relations.jl
+++ b/src/relations.jl
@@ -1164,10 +1164,9 @@ function supersaturation(
     phase::Phase,
 ) where {FT <: Real}
 
-    p_v_sat::FT = saturation_vapor_pressure(param_set, T, phase)
-    p_v::FT = vapor_specific_humidity(q) * (ρ * TP.R_v(param_set) * T)
+    p_v_sat = saturation_vapor_pressure(param_set, T, phase)
 
-    return p_v / p_v_sat - FT(1)
+    return supersaturation(param_set, q, ρ, T, p_v_sat)
 end
 function supersaturation(
     param_set::APS,