diff --git a/regtests/bin/matrix.base b/regtests/bin/matrix.base
index 824b358f1..4b7e1e71a 100755
--- a/regtests/bin/matrix.base
+++ b/regtests/bin/matrix.base
@@ -1957,6 +1957,7 @@
     echo "$rtst                  -w work_IC4_M7                -i input_IC4_M7      $ww3 ww3_tic1.1" >> matrix.body
     echo "$rtst                  -w work_IC4_M8                -i input_IC4_M8      $ww3 ww3_tic1.1" >> matrix.body
     echo "$rtst                  -w work_IC4_M9                -i input_IC4_M9      $ww3 ww3_tic1.1" >> matrix.body
+    echo "$rtst                  -w work_IC4_M10               -i input_IC4_M10     $ww3 ww3_tic1.1" >> matrix.body
     echo "$rtst -g 1000m         -w work_IC5_M1                -i input_IC5_M1      $ww3 ww3_tic1.1" >> matrix.body
     echo "$rtst -g 1000m         -w work_IC5_M2                -i input_IC5_M2      $ww3 ww3_tic1.1" >> matrix.body
     echo "$rtst -g 1000m         -w work_IC5_M3                -i input_IC5_M3      $ww3 ww3_tic1.1" >> matrix.body
diff --git a/regtests/ww3_tic1.1/info b/regtests/ww3_tic1.1/info
index 589317ea5..bb3c7e84a 100644
--- a/regtests/ww3_tic1.1/info
+++ b/regtests/ww3_tic1.1/info
@@ -54,6 +54,7 @@
 #            IC4METHOD = 8 - Meylan et al. (2018) ; Liu et al. (2020)       #
 #                            (NB: redundant with IC5+IC5VEMOD=3)            #
 #            IC4METHOD = 9 - RYW (2021) ; Yu et al. (2022)                  #
+#            IC4METHOD = 10 - Meylan et al. (2021)                          #
 #          IC5 = Choose from three different effective medium models        #
 #            IC5VEMOD  = 1 - Extended Fox and Squire model (EFS)            #
 #            IC5VEMOD  = 2 - Robinson and Palmer model (RP)                 #
@@ -101,6 +102,14 @@
 #               'IC1' 19680606 000000   5.35E-6                             #
 #               'IC2' 19680606 000000   16.05E-6                            #
 #                                                                           #
+#      ------------> &SIC4 IC4METHOD = 10 /                                 #
+#            ...ICECOEF1, ICECOEF5 are required:                            #
+#               T T     Ice parameter 1                                     #
+#               T T     Ice parameter 5                                     #
+#            ...                                                            #
+#               'IC1' 19680606 000000   0.2                                 #
+#               'IC5' 19680606 000000   0.459                               #
+#                                                                           #
 #  Reference (w/plots): Rogers and Orzech, NRL Memorandum Report (2013)     #
 #  available from http://www7320.nrlssc.navy.mil/pubs.php                   #
 #  (This report only covers IC1 and IC2, not IC3, which is newer)           #
diff --git a/regtests/ww3_tic1.1/input_IC4_M10/namelists_1-D.nml b/regtests/ww3_tic1.1/input_IC4_M10/namelists_1-D.nml
new file mode 100644
index 000000000..53fac9fd0
--- /dev/null
+++ b/regtests/ww3_tic1.1/input_IC4_M10/namelists_1-D.nml
@@ -0,0 +1,2 @@
+&SIC4 IC4METHOD = 10 /
+END OF NAMELISTS
diff --git a/regtests/ww3_tic1.1/input_IC4_M10/points.list b/regtests/ww3_tic1.1/input_IC4_M10/points.list
new file mode 100644
index 000000000..e2a0afe3d
--- /dev/null
+++ b/regtests/ww3_tic1.1/input_IC4_M10/points.list
@@ -0,0 +1,16 @@
+0.00 0. 'Point 1 '
+1.00E3 0. 'Point 2 '
+2.00E3 0. 'Point 3 '
+3.00E3 0. 'Point 4 '
+4.00E3 0. 'Point 5 '
+5.00E3 0. 'Point 6 '
+6.00E3 0. 'Point 7 '
+7.00E3 0. 'Point 8 '
+8.00E3 0. 'Point 9 '
+9.00E3 0. 'Point 10 '
+10.00E3 0. 'Point 11 '
+11.00E3 0. 'Point 12 '
+12.00E3 0. 'Point 13 '
+13.00E3 0. 'Point 14 '
+14.00E3 0. 'Point 15 '
+15.00E3 0. 'Point 16 '
diff --git a/regtests/ww3_tic1.1/input_IC4_M10/switch b/regtests/ww3_tic1.1/input_IC4_M10/switch
new file mode 100644
index 000000000..31ef85bae
--- /dev/null
+++ b/regtests/ww3_tic1.1/input_IC4_M10/switch
@@ -0,0 +1 @@
+NOGRB SHRD PR3 UQ FLX2 LN0 ST0 NL0 BT0 DB0 TR0 BS0 IC4 IS0 REF0 WNT1 WNX1 CRT1 CRX1 O0 O1 O2 O3 O4 O5 O6 O7
diff --git a/regtests/ww3_tic1.1/input_IC4_M10/ww3_grid.inp b/regtests/ww3_tic1.1/input_IC4_M10/ww3_grid.inp
new file mode 100644
index 000000000..19e03a81c
--- /dev/null
+++ b/regtests/ww3_tic1.1/input_IC4_M10/ww3_grid.inp
@@ -0,0 +1,43 @@
+$ WAVEWATCH III Grid preprocessor input file
+$ ------------------------------------------
+  '1-D parameterized ice test    '
+$
+$  1.1 0.04118 25 24 0.0
+   1.1 0.0418  31 36 5.0
+$
+   F T F F F T
+  60. 60. 60. 60.
+$
+$ IC4METHOD determines calculation
+$ IC4METHOD = 1 - Wadhams et al. (1988)
+$ IC4METHOD = 2 - Meylan et al. (2014)
+$ IC4METHOD = 3 - Kohout & Meylan (2008) in Horvat & Tziperman (2015)
+$ IC4METHOD = 4 - Kohout et al. (2014)
+$ IC4METHOD = 5 - Simple ki step function
+$ IC4METHOD = 6 - Simple ki step function via namelist
+$ IC4METHOD = 7 - Doble et al. (GRL 2015)
+$ IC4METHOD = 8 - Meylan et al. (2018) ; Liu et al. (2020)
+$ IC4METHOD = 9 - RYW (2021) ; Yu et al. (2022)
+$ IC4M8 Fit to R21A L ChfM2=0.059
+$ IC4M10 
+  &SIC4 IC4METHOD = 10 ,  IC4CN =   0.059/
+END OF NAMELISTS
+$
+  'RECT' F 'NONE'
+   156  3
+    1.0E3   1.0E3  1.
+   -1.0E3  -1.0E3  1.
+$ dlim dmin file# scale layout# format# formatdescrip filetype# filenm
+ -0.1 0.1 401  -1.0 1 1 '(....)'  'NAME' '../input_IC1/depth1d.flat'
+$
+  10  1 1 '(....)' 'PART' 'input'
+$
+$ First grid
+$
+   2  2  F
+$
+   0  0  F
+   0  0  F
+   0  0
+$
+   0. 0. 0. 0.  0
diff --git a/regtests/ww3_tic1.1/input_IC4_M10/ww3_grid.nml b/regtests/ww3_tic1.1/input_IC4_M10/ww3_grid.nml
new file mode 100644
index 000000000..e3f8dd58a
--- /dev/null
+++ b/regtests/ww3_tic1.1/input_IC4_M10/ww3_grid.nml
@@ -0,0 +1,81 @@
+! -------------------------------------------------------------------- !
+! WAVEWATCH III - ww3_grid.nml - Grid pre-processing                   !
+! -------------------------------------------------------------------- !
+
+! -------------------------------------------------------------------- !
+! Define the spectrum parameterization via SPECTRUM_NML namelist
+! -------------------------------------------------------------------- !
+&SPECTRUM_NML
+  SPECTRUM%XFR       =  1.1
+  SPECTRUM%FREQ1     =  0.0418
+  SPECTRUM%NK        =  31
+  SPECTRUM%NTH       =  36
+  SPECTRUM%THOFF     =  5.0
+/
+
+! -------------------------------------------------------------------- !
+! Define the run parameterization via RUN_NML namelist
+! -------------------------------------------------------------------- !
+&RUN_NML
+  RUN%FLCX         =  T
+  RUN%FLSOU        =  T
+/
+
+! -------------------------------------------------------------------- !
+! Define the timesteps parameterization via TIMESTEPS_NML namelist
+! -------------------------------------------------------------------- !
+&TIMESTEPS_NML
+  TIMESTEPS%DTMAX        =  60.
+  TIMESTEPS%DTXY         =  60.
+  TIMESTEPS%DTKTH        =  60.
+  TIMESTEPS%DTMIN        =  60.
+/
+
+! -------------------------------------------------------------------- !
+! Define the grid to preprocess via GRID_NML namelist
+! -------------------------------------------------------------------- !
+&GRID_NML
+  GRID%NAME         =  '1-D parameterized ice test'
+  GRID%NML          =  '../input_IC4_M10/namelists_1-D.nml'
+  GRID%TYPE         =  'RECT'
+  GRID%COORD        =  'CART'
+  GRID%CLOS         =  'NONE'
+  GRID%ZLIM         =  -0.1
+  GRID%DMIN         =  0.1
+/
+
+! -------------------------------------------------------------------- !
+! Define the rectilinear grid type via RECT_NML namelist
+! -------------------------------------------------------------------- !
+&RECT_NML
+  RECT%NX           =  156
+  RECT%NY           =  3
+  RECT%SX           =  1.0E3
+  RECT%SY           =  1.0E3
+  RECT%X0           =  -1.0E3
+  RECT%Y0           =  -1.0E3
+/
+
+! -------------------------------------------------------------------- !
+! Define the depth to preprocess via DEPTH_NML namelist
+! -------------------------------------------------------------------- !
+&DEPTH_NML
+  DEPTH%SF        =  -1.0
+  DEPTH%FILENAME  =  '../input_IC1/depth1d.flat'
+/
+
+! -------------------------------------------------------------------- !
+! Define the input boundary points via INBND_COUNT_NML and
+!                                      INBND_POINT_NML namelist
+! -------------------------------------------------------------------- !
+&INBND_COUNT_NML
+  INBND_COUNT%N_POINT    =  1
+/
+
+&INBND_POINT_NML
+  INBND_POINT(1)         =  2 2 F
+/
+
+! -------------------------------------------------------------------- !
+! WAVEWATCH III - end of namelist                                      !
+! -------------------------------------------------------------------- !
diff --git a/regtests/ww3_tic1.1/input_IC4_M10/ww3_ounf.inp b/regtests/ww3_tic1.1/input_IC4_M10/ww3_ounf.inp
new file mode 100644
index 000000000..4104d759e
--- /dev/null
+++ b/regtests/ww3_tic1.1/input_IC4_M10/ww3_ounf.inp
@@ -0,0 +1,20 @@
+$ WAVEWATCH III Grid output post-processing (netcdf)
+$---------------------------------------------------
+  19680606 000000 3600. 99
+N
+$  Options: DPT CUR WND DT  WLV ICE HS  L T02 T01 TM1 FP  DIR SPR DP EF 
+$           TH1M STH1M PHS PTP PLP PDIR PSP WSF TWS PNR UST CHA CGE FAW 
+$           TAW TWA WCC WCF WCH WCM SXY TWO BHD FOC TUS USS P2S WN USF 
+$           P2L ABR UBR BED FBB TBB MSS MSC DTD FCT CFX CFT CFK US1 US2
+DPT WLV HS DIR
+$
+  3 4
+  0 1 2
+  F
+  ww3.
+  4
+  1 999 1 999 3 2
+$
+$ -------------------------------------------------------------------- $
+$ End of input file                                                    $
+$ -------------------------------------------------------------------- $
diff --git a/regtests/ww3_tic1.1/input_IC4_M10/ww3_ounf.nml b/regtests/ww3_tic1.1/input_IC4_M10/ww3_ounf.nml
new file mode 100644
index 000000000..46aa758fa
--- /dev/null
+++ b/regtests/ww3_tic1.1/input_IC4_M10/ww3_ounf.nml
@@ -0,0 +1,29 @@
+! -------------------------------------------------------------------- !
+! WAVEWATCH III ww3_ounf.nml - Grid output post-processing             !
+! -------------------------------------------------------------------- !
+
+! -------------------------------------------------------------------- !
+! Define the output fields to postprocess via FIELD_NML namelist
+! -------------------------------------------------------------------- !
+&FIELD_NML
+  FIELD%TIMESTART        =  '19680606 000000'
+  FIELD%TIMESTRIDE       =  '3600.'
+  FIELD%TIMECOUNT        =  '99'
+  FIELD%TIMESPLIT        =  4
+  FIELD%LIST             =  'DPT WLV HS DIR'
+  FIELD%PARTITION        =  '0 1 2'
+  FIELD%SAMEFILE         =  F
+  FIELD%TYPE             =  4
+/
+
+! -------------------------------------------------------------------- !
+! Define the content of the output file via FILE_NML namelist
+! -------------------------------------------------------------------- !
+&FILE_NML
+  FILE%IXN           = 999
+  FILE%IYN           = 999
+/
+
+! -------------------------------------------------------------------- !
+! WAVEWATCH III - end of namelist                                      !
+! -------------------------------------------------------------------- !
diff --git a/regtests/ww3_tic1.1/input_IC4_M10/ww3_outf.inp b/regtests/ww3_tic1.1/input_IC4_M10/ww3_outf.inp
new file mode 100644
index 000000000..2b4c6bca8
--- /dev/null
+++ b/regtests/ww3_tic1.1/input_IC4_M10/ww3_outf.inp
@@ -0,0 +1,13 @@
+$ WAVEWATCH III Grid output post-processing
+$ -----------------------------------------
+  19680606 000000 3600. 99
+N
+$  Options: DPT CUR WND DT  WLV ICE HS  L T02 T01 TM1 FP  DIR SPR DP EF 
+$           TH1M STH1M PHS PTP PLP PDIR PSP WSF TWS PNR UST CHA CGE FAW 
+$           TAW TWA WCC WCF WCH WCM SXY TWO BHD FOC TUS USS P2S WN USF 
+$           P2L ABR UBR BED FBB TBB MSS MSC DTD FCT CFX CFT CFK US1 US2
+DPT WLV HS DIR
+$
+  3 0
+$
+ 1 999 1 999 1 1
diff --git a/regtests/ww3_tic1.1/input_IC4_M10/ww3_outp_spec.inp b/regtests/ww3_tic1.1/input_IC4_M10/ww3_outp_spec.inp
new file mode 100644
index 000000000..b500e0ca4
--- /dev/null
+++ b/regtests/ww3_tic1.1/input_IC4_M10/ww3_outp_spec.inp
@@ -0,0 +1,19 @@
+$ WAVEWATCH III Point output post-processing
+$ ------------------------------------------
+  19680606 120000   3600. 1
+$
+   1
+   2
+   3
+   4
+   5
+   6
+   7
+   8
+   9
+  10
+  11
+  -1
+$
+   1
+   2  -1.  0.  33  F
diff --git a/regtests/ww3_tic1.1/input_IC4_M10/ww3_outp_tab50.inp b/regtests/ww3_tic1.1/input_IC4_M10/ww3_outp_tab50.inp
new file mode 100644
index 000000000..826bd422d
--- /dev/null
+++ b/regtests/ww3_tic1.1/input_IC4_M10/ww3_outp_tab50.inp
@@ -0,0 +1,19 @@
+$ WAVEWATCH III Point output post-processing
+$ ------------------------------------------
+  19680606 000000  600. 9999
+$
+   1
+   2
+   3
+   4
+   5
+   6
+   7
+   8
+   9
+  10
+  11
+  -1
+$
+   2
+   2  50
diff --git a/regtests/ww3_tic1.1/input_IC4_M10/ww3_outp_tab51.inp b/regtests/ww3_tic1.1/input_IC4_M10/ww3_outp_tab51.inp
new file mode 100644
index 000000000..e54faed46
--- /dev/null
+++ b/regtests/ww3_tic1.1/input_IC4_M10/ww3_outp_tab51.inp
@@ -0,0 +1,10 @@
+$ WAVEWATCH III Point output post-processing
+$ ------------------------------------------
+  19680606 000000    900. 49
+$
+$  1
+  11
+  -1
+$
+   2
+   2  51
diff --git a/regtests/ww3_tic1.1/input_IC4_M10/ww3_prep_icecon.inp b/regtests/ww3_tic1.1/input_IC4_M10/ww3_prep_icecon.inp
new file mode 100644
index 000000000..26a94221f
--- /dev/null
+++ b/regtests/ww3_tic1.1/input_IC4_M10/ww3_prep_icecon.inp
@@ -0,0 +1,38 @@
+$ -------------------------------------------------------------------- $
+$ WAVEWATCH III Field preprocessor input file                          $
+$ -------------------------------------------------------------------- $
+$ Mayor types of field and time flag
+$   Field types  :  IC1, IC2, IC3, IC4, IC5 => Ice parameters (5)
+$                   MDN   => Mud densities
+$                   MTH   => Mud thicknesses
+$                   MVS   => Mud viscosities 
+$                   ICE   => Ice concentrations.
+$                   LEV   => Water levels.
+$                   WND   => Winds.
+$                   WNS   => Winds (including air-sea temp. dif.)
+$                   CUR   => Currents.
+$   Format types :  AI    Transfer field 'as is'.
+$                   LL    Field defined on longitude-latitude grid.
+$                   F1    Arbitrary grid, longitude and latitude of
+$                         each grid point given in separate file.
+$                   F2    Like F1, composite of 2 fields.
+$   Time flag    : If true, time is included in file.
+$   Header flag  : If true, write header on "*.ww3" data file
+$
+   'ICE' 'AI' T T
+$
+$ Additional time input ---------------------------------------------- $
+$ If time flag is .FALSE., give time of field in yyyymmdd hhmmss format.
+$
+$ 19680606 000000 
+$
+$ Define data files -------------------------------------------------- $
+$ The first input line identifies the file format with FROM, IDLA and
+$ IDFM, the second (third) lines give the file unit number and name.
+$
+   'NAME' 1 2 '(I10,1x,I10)' '(1000(F6.2))' 
+  2345 '../input_IC2_nondisp/icecon.156x3.txt'
+$
+$ -------------------------------------------------------------------- $
+$ End of input file                                                    $
+$ -------------------------------------------------------------------- $
diff --git a/regtests/ww3_tic1.1/input_IC4_M10/ww3_shel.inp b/regtests/ww3_tic1.1/input_IC4_M10/ww3_shel.inp
new file mode 100644
index 000000000..2be39573e
--- /dev/null
+++ b/regtests/ww3_tic1.1/input_IC4_M10/ww3_shel.inp
@@ -0,0 +1,69 @@
+$ WAVEWATCH III shell input file
+$ ------------------------------
+   T T     Ice parameter 1
+   F F     Ice parameter 2
+   F F     Ice parameter 3
+   F F     Ice parameter 4
+   T T     Ice parameter 5
+   F F     Mud parameter 1
+   F F     Mud parameter 2
+   F F     Mud parameter 3
+   F F     Water levels
+   F F     Currents
+   F F     Winds
+   T F     Ice concentrations
+   F F     Atmospheric momentum
+   F F     Air density
+   F       Assimilation data : Mean parameters
+   F       Assimilation data : 1-D spectra
+   F       Assimilation data : 2-D spectra.
+$
+   19680606 000000
+   19680606 120000
+$
+   1
+$
+   19680606 000000    900  19680606 120000
+N
+$ Options: DPT CUR WND DT  WLV ICE HS  L T02 T01 TM1 FP  DIR SPR DP EF 
+$          TH1M STH1M PHS PTP PLP PDIR PSP WSF TWS PNR UST CHA CGE FAW 
+$          TAW TWA WCC WCF WCH WCM SXY TWO BHD FOC TUS USS P2S WN USF 
+$          P2L ABR UBR BED FBB TBB MSS MSC DTD FCT CFX CFT CFK US1 US2
+DPT HS ICE DIR EF
+   19680606 000000    900  19680606 120000
+      0.00    0.  'Point   1 '
+      1.00E3  0.  'Point   2 '
+      2.00E3  0.  'Point   3 '
+      3.00E3  0.  'Point   4 '
+      4.00E3  0.  'Point   5 '
+      5.00E3  0.  'Point   6 '
+      6.00E3  0.  'Point   7 '
+      7.00E3  0.  'Point   8 '
+      8.00E3  0.  'Point   9 '
+      9.00E3  0.  'Point  10 '
+     10.00E3  0.  'Point  11 '
+     11.00E3  0.  'Point  12 '
+     12.00E3  0.  'Point  13 '
+     13.00E3  0.  'Point  14 '
+     14.00E3  0.  'Point  15 '
+     15.00E3  0.  'Point  16 '
+      0.    0.  'STOPSTRING'
+   19680606 000000      0  19680606 120000
+   19680606 000000      0  19680606 120000
+   19680606 000000      0  19680606 120000
+   19680606 000000      0  19680606 120000
+$
+$ Testing of output through parameter list (C/TPAR) ------------------ $
+$    Time for output and field flags as in above output type 1.
+$
+$  19680606 014500
+$    T T T T T  T T T T T  T T T T T  T
+$
+$ Homogeneous field data --------------------------------------------- $
+$ constant case:
+$ Meylan et al. (2014) pg 5050 : a=2.12e-3 and b=4.59e-2
+   'IC1' 19680606 000000   0.2
+   'IC5' 19680606 000000   4.59E-2
+  'STP'
+$
+$ -------------------------------------------------------------------- $
diff --git a/regtests/ww3_tic1.1/input_IC4_M10/ww3_strt.inp b/regtests/ww3_tic1.1/input_IC4_M10/ww3_strt.inp
new file mode 100644
index 000000000..49747e41a
--- /dev/null
+++ b/regtests/ww3_tic1.1/input_IC4_M10/ww3_strt.inp
@@ -0,0 +1,17 @@
+$ WAVEWATCH III Initial conditions input file
+$ -------------------------------------------
+  2
+$  0.1  0.0001 225. 12   0.    -5.E3  0.  5.E3  1.0
+$  0.1  0.0001 315. 12   0.    -5.E3  0.  5.E3  1.0
+$  0.1  0.0001 240.  2   0.    -5.E3  0.  5.E3  1.0
+$  fp   sip    thm  ncos xm     six   ym  siy  hmax
+$   0.1  0.0001 270. 12   0.    -5.E3  0.  5.E3  1.0
+$  0.1  0.0001 270.  2   0.    -5.E3  0.  5.E3  1.0
+$  0.1  0.0001 300.  2   0.    -5.E3  0.  5.E3  1.0
+$  0.1  0.0001 135. 12  50.E3  -5.E3  0.  5.E3  1.0
+$  0.1  0.0001  45. 12  50.E3  -5.E3  0.  5.E3  1.0
+$  0.1  0.0001 120.  2  50.E3  -5.E3  0.  5.E3  1.0
+$  0.1  0.0001  60.  2  50.E3  -5.E3  0.  5.E3  1.0
+$
+$  alpha  fp  thm   gamma  sigA sigB  xm  six   ym siy 
+   0.0081 0.1 270.0 1.0    0.07 0.09  0.  -5.E3 0. 5.E3