diff --git a/src/EarthSystemModels/InterfaceComputations/atmosphere_sea_ice_fluxes.jl b/src/EarthSystemModels/InterfaceComputations/atmosphere_sea_ice_fluxes.jl
index ac729923..4c51a80a 100644
--- a/src/EarthSystemModels/InterfaceComputations/atmosphere_sea_ice_fluxes.jl
+++ b/src/EarthSystemModels/InterfaceComputations/atmosphere_sea_ice_fluxes.jl
@@ -110,8 +110,7 @@ end
 
     local_interior_state = (u=uˢⁱ, v=vˢⁱ, T=Tᵒᶜ, S=Sᵒᶜ, hi=hˢⁱ, hs=hˢⁿ, hc=hc)
 
-    # Local radiative state at this cell. Returns zero-valued state when
-    # radiation is off.
+    # Local radiative state at this cell. Returns zero-valued state when radiation is off.
     radiation_state = air_sea_ice_interface_radiation_state(radiation_kernel_props,
                                                             radiation_exchanger_state,
                                                             i, j, kᴺ, grid, time)
diff --git a/src/NumericalEarth.jl b/src/NumericalEarth.jl
index e66225b1..79bf3717 100644
--- a/src/NumericalEarth.jl
+++ b/src/NumericalEarth.jl
@@ -58,6 +58,7 @@ export
     InterfaceRadiationFlux,
     LatitudeDependentAlbedo,
     TabulatedAlbedo,
+    SeaIceAlbedo,
     SimilarityTheoryFluxes,
     CoefficientBasedFluxes,
     SimilarityScales,
diff --git a/src/Radiations/Radiations.jl b/src/Radiations/Radiations.jl
index 67b4a6ba..ff1b6696 100644
--- a/src/Radiations/Radiations.jl
+++ b/src/Radiations/Radiations.jl
@@ -5,6 +5,7 @@ export PrescribedRadiation,
        InterfaceRadiationFlux,
        LatitudeDependentAlbedo,
        TabulatedAlbedo,
+       SeaIceAlbedo,
        default_stefan_boltzmann_constant
 
 # CODATA 2018 value of the Stefan–Boltzmann constant, in W m⁻² K⁻⁴.
@@ -36,6 +37,7 @@ include("interface_radiation_flux.jl")
 include("radiation_kernels.jl")
 include("latitude_dependent_albedo.jl")
 include("tabulated_albedo.jl")
+include("sea_ice_albedo.jl")
 include("prescribed_radiation.jl")
 include("prescribed_radiation_regridder.jl")
 include("interpolate_radiation_state.jl")
diff --git a/src/Radiations/sea_ice_albedo.jl b/src/Radiations/sea_ice_albedo.jl
new file mode 100644
index 00000000..ee38dc9f
--- /dev/null
+++ b/src/Radiations/sea_ice_albedo.jl
@@ -0,0 +1,133 @@
+"""
+    SeaIceAlbedo{FT, HI, HS, TS}
+
+Sea ice albedo parameterization following the CCSM3 scheme (Briegleb et al. 2004).
+
+Computes broadband albedo as a function of ice thickness, snow depth, and surface
+temperature. The scheme blends between bare ice and snow-covered albedos, with
+a temperature-dependent reduction near the melting point to implicitly represent
+melt pond formation.
+
+Algorithm:
+1. Base cold albedos: bare ice (0.53) and snow-covered (0.82)
+2. Temperature reduction within 1C of melting: Δα_ice = 0.075, Δα_snow = 0.10
+3. Thin-ice transition to ocean albedo below h_amin = 0.5 m
+4. Snow cover interpolation: full snow albedo at h_snow > h_smin = 0.02 m
+
+References:
+- Briegleb, B.P., C.M. Bitz, E.C. Hunke, W.H. Lipscomb, and M.M. Schramm (2004):
+  Scientific description of the sea ice component in CCSM3. NCAR Tech Note.
+- Briegleb, B.P. and B. Light (2007): NCAR/TN-472+STR.
+"""
+struct SeaIceAlbedo{FT, HI, HS, TS}
+    # Cold base albedos (broadband, approx 0.52 * vis + 0.48 * nir)
+    ice_albedo :: FT    # 0.52*0.73 + 0.48*0.33 = 0.538 ≈ 0.54
+    snow_albedo :: FT   # 0.52*0.96 + 0.48*0.68 = 0.825 ≈ 0.83
+    # Melt reduction
+    ice_melt_reduction :: FT    # 0.075
+    snow_melt_reduction :: FT   # 0.10
+    melting_temperature :: FT   # 0 C
+    temperature_range :: FT     # 1 C
+    # Thickness scales
+    ocean_albedo :: FT          # 0.06
+    minimum_ice_thickness :: FT # 0.5 m
+    minimum_snow_depth :: FT    # 0.02 m
+    # References to model fields
+    ice_thickness :: HI
+    snow_thickness :: HS
+    surface_temperature :: TS
+end
+
+Adapt.adapt_structure(to, α::SeaIceAlbedo) =
+    SeaIceAlbedo(α.ice_albedo,
+                      α.snow_albedo,
+                      α.ice_melt_reduction,
+                      α.snow_melt_reduction,
+                      α.melting_temperature,
+                      α.temperature_range,
+                      α.ocean_albedo,
+                      α.minimum_ice_thickness,
+                      α.minimum_snow_depth,
+                      Adapt.adapt(to, α.ice_thickness),
+                      Adapt.adapt(to, α.snow_thickness),
+                      Adapt.adapt(to, α.surface_temperature))
+
+"""
+    SeaIceAlbedo(ice_thickness, snow_thickness, surface_temperature;
+                      ice_albedo = 0.54,
+                      snow_albedo = 0.83,
+                      ice_melt_reduction = 0.075,
+                      snow_melt_reduction = 0.10,
+                      melting_temperature = 0.0,
+                      temperature_range = 1.0,
+                      ocean_albedo = 0.06,
+                      minimum_ice_thickness = 0.5,
+                      minimum_snow_depth = 0.02)
+
+Construct a CCSM3 sea ice albedo parameterization. Requires references to the sea ice
+model's ice thickness, snow thickness, and surface temperature fields.
+
+Broadband albedos are approximate averages of the visible and near-IR bands
+weighted by solar spectrum (52% visible, 48% near-IR):
+- ice_albedo ≈ 0.52 x 0.73 + 0.48 x 0.33 ≈ 0.54
+- snow_albedo ≈ 0.52 x 0.96 + 0.48 x 0.68 ≈ 0.83
+"""
+function SeaIceAlbedo(ice_thickness, snow_thickness, surface_temperature;
+                      FT = Float64,
+                      ice_albedo = 0.54,
+                      snow_albedo = 0.83,
+                      ice_melt_reduction = 0.075,
+                      snow_melt_reduction = 0.10,
+                      melting_temperature = 0.0,
+                      temperature_range = 1.0,
+                      ocean_albedo = 0.06,
+                      minimum_ice_thickness = 0.5,
+                      minimum_snow_depth = 0.02)
+
+    return SeaIceAlbedo(convert(FT, ice_albedo),
+                        convert(FT, snow_albedo),
+                        convert(FT, ice_melt_reduction),
+                        convert(FT, snow_melt_reduction),
+                        convert(FT, melting_temperature),
+                        convert(FT, temperature_range),
+                        convert(FT, ocean_albedo),
+                        convert(FT, minimum_ice_thickness),
+                        convert(FT, minimum_snow_depth),
+                        ice_thickness,
+                        snow_thickness,
+                        surface_temperature)
+end
+
+Base.summary(::SeaIceAlbedo{FT}) where FT = "SeaIceAlbedo{$FT}"
+Base.show(io::IO, α::SeaIceAlbedo{FT}) where FT =
+    print(io, "SeaIceAlbedo{$FT}(ice=", α.ice_albedo,
+              ", snow=", α.snow_albedo, ")")
+
+@inline function NumericalEarth.stateindex(α::SeaIceAlbedo, i, j, k, grid, time, loc, args...)
+    @inbounds hi = α.ice_thickness[i, j, 1]
+    @inbounds Ts = α.surface_temperature[i, j, 1]
+
+    # Snow thickness: may be nothing (no snow model)
+    hs = get_snow_thickness(α.snow_thickness, i, j, grid)
+
+    # Temperature-dependent reduction (implicit melt ponds)
+    Tm = α.melting_temperature
+    ΔT = α.temperature_range
+    fT = clamp((Ts - Tm + ΔT) / ΔT, zero(Ts), one(Ts))
+
+    αi = α.ice_albedo  - α.ice_melt_reduction  * fT
+    αs = α.snow_albedo - α.snow_melt_reduction * fT
+
+    # Thin ice → transition to ocean albedo
+    αo = α.ocean_albedo
+    fh = clamp(hi / α.minimum_ice_thickness, zero(hi), one(hi))
+    αi = αo + (αi - αo) * fh
+
+    # Snow cover blending
+    fs = clamp(hs / α.minimum_snow_depth, zero(hs), one(hs))
+    return fs * αs + (1 - fs) * αi
+end
+
+# Helper to handle nothing snow thickness (no snow model)
+@inline get_snow_thickness(hs::Nothing, i, j, grid) = zero(grid)
+@inline get_snow_thickness(hs, i, j, grid) = @inbounds hs[i, j, 1]
diff --git a/test/test_sea_ice_albedo.jl b/test/test_sea_ice_albedo.jl
new file mode 100644
index 00000000..6c404827
--- /dev/null
+++ b/test/test_sea_ice_albedo.jl
@@ -0,0 +1,121 @@
+include("runtests_setup.jl")
+
+using NumericalEarth: stateindex
+using NumericalEarth.Radiations: SeaIceAlbedo
+
+using Oceananigans.Units: Time
+
+@testset "SeaIceAlbedo" begin
+    for arch in test_architectures
+        A = typeof(arch)
+
+        grid = RectilinearGrid(arch;
+                               size = (4, 4, 1),
+                               extent = (1, 1, 1),
+                               topology = (Periodic, Periodic, Bounded))
+
+        hi = Field{Center, Center, Nothing}(grid)
+        hs = Field{Center, Center, Nothing}(grid)
+        Ts = Field{Center, Center, Nothing}(grid)
+
+        @testset "Constructor [$A]" begin
+            α = SeaIceAlbedo(hi, hs, Ts)
+            @test α isa SeaIceAlbedo{Float64}
+            @test α.ice_albedo == 0.54
+            @test α.snow_albedo == 0.83
+            @test α.ocean_albedo == 0.06
+
+            α32 = SeaIceAlbedo(hi, hs, Ts; FT = Float32)
+            @test α32 isa SeaIceAlbedo{Float32}
+        end
+
+        @testset "Nothing snow thickness [$A]" begin
+            α = SeaIceAlbedo(hi, nothing, Ts)
+            @test α.snow_thickness === nothing
+        end
+
+        @testset "Cold thick ice, no snow [$A]" begin
+            # Thick ice, well below melting: should give cold bare-ice albedo
+            set!(hi, 2.0)  # 2 m (>> minimum_ice_thickness = 0.5)
+            set!(hs, 0.0)
+            set!(Ts, -20.0) # well below melting
+
+            α = SeaIceAlbedo(hi, hs, Ts)
+            time = Time(0.0)
+            loc = (Center, Center, Center)
+
+            @allowscalar begin
+                val = stateindex(α, 1, 1, 1, grid, time, loc)
+                # With Ts = -20, fT = clamp((-20 - 0 + 1)/1, 0, 1) = 0
+                # αi = 0.54 - 0 = 0.54, no thin-ice effect (fh=1), no snow (fs=0)
+                @test val ≈ 0.54
+            end
+        end
+
+        @testset "Cold thick ice, deep snow [$A]" begin
+            set!(hi, 2.0)
+            set!(hs, 0.1)   # >> minimum_snow_depth = 0.02
+            set!(Ts, -20.0)
+
+            α = SeaIceAlbedo(hi, hs, Ts)
+            time = Time(0.0)
+            loc = (Center, Center, Center)
+
+            @allowscalar begin
+                val = stateindex(α, 1, 1, 1, grid, time, loc)
+                # fs = clamp(0.1/0.02, 0, 1) = 1 → full snow albedo
+                @test val ≈ 0.83
+            end
+        end
+
+        @testset "Melting ice, no snow [$A]" begin
+            set!(hi, 2.0)
+            set!(hs, 0.0)
+            set!(Ts, 0.0) # at melting point
+
+            α = SeaIceAlbedo(hi, hs, Ts)
+            time = Time(0.0)
+            loc = (Center, Center, Center)
+
+            @allowscalar begin
+                val = stateindex(α, 1, 1, 1, grid, time, loc)
+                # fT = clamp((0 - 0 + 1)/1, 0, 1) = 1
+                # αi = 0.54 - 0.075 = 0.465
+                @test val ≈ 0.54 - 0.075
+            end
+        end
+
+        @testset "Thin ice transitions to ocean albedo [$A]" begin
+            set!(hi, 0.0)  # no ice
+            set!(hs, 0.0)
+            set!(Ts, -10.0)
+
+            α = SeaIceAlbedo(hi, hs, Ts)
+            time = Time(0.0)
+            loc = (Center, Center, Center)
+
+            @allowscalar begin
+                val = stateindex(α, 1, 1, 1, grid, time, loc)
+                # fh = clamp(0/0.5, 0, 1) = 0 → pure ocean albedo
+                @test val ≈ 0.06
+            end
+        end
+
+        @testset "Partial snow cover [$A]" begin
+            set!(hi, 2.0)
+            set!(hs, 0.01) # half of minimum_snow_depth
+            set!(Ts, -20.0)
+
+            α = SeaIceAlbedo(hi, hs, Ts)
+            time = Time(0.0)
+            loc = (Center, Center, Center)
+
+            @allowscalar begin
+                val = stateindex(α, 1, 1, 1, grid, time, loc)
+                # fs = clamp(0.01/0.02, 0, 1) = 0.5
+                # αi = 0.54, αs = 0.83
+                @test val ≈ 0.5 * 0.83 + 0.5 * 0.54
+            end
+        end
+    end
+end