Index: /issm/trunk-jpl/src/m/classes/SMBgemb.m
===================================================================
--- /issm/trunk-jpl/src/m/classes/SMBgemb.m	(revision 27235)
+++ /issm/trunk-jpl/src/m/classes/SMBgemb.m	(revision 27236)
@@ -72,4 +72,8 @@
 		% 1: default value of 1, in areas with grain radius below teThresh
 		% 2: default value of 1, in areas with grain radius below teThresh and areas of dry snow (not bare ice or wet) at the surface
+
+		tcIdx   = NaN; %method for calculating thermal conductivity (default is 1)
+		% 1: after Sturm et al, 1997
+		% 2: after Calonne et al., 2011
 
 		swIdx  = NaN; %apply all SW to top grid cell (0) or allow SW to penetrate surface (1) (default 0, if swIdx=1 and aIdx=2, function of effective radius (Brun et al., 1992) or else dependent on snow density (taken from Bassford, 2002))
@@ -203,4 +207,8 @@
 				'2: default value of 1, in areas with grain radius below teThresh and areas of dry snow (not bare ice or wet) at the surface'});
 
+			fielddisplay(self,'tcIdx',{'method for calculating thermal conductivity (default is 1)',...
+				'1: after Sturm et al, 1997',...
+				'2: after Calonne et al., 2011'});
+
 			%snow properties init
 			fielddisplay(self,'Dzini','Initial cell depth when restart [m]');
@@ -343,4 +351,5 @@
 			self.aIdx = 1;
 			self.eIdx = 1;
+			self.tcIdx = 1;
 			self.swIdx = 0;
 			self.denIdx = 2;
@@ -426,4 +435,5 @@
 			md = checkfield(md,'fieldname','smb.aIdx','NaN',1,'Inf',1,'values',[0,1,2,3,4]);
 			md = checkfield(md,'fieldname','smb.eIdx','NaN',1,'Inf',1,'values',[0,1,2]);
+			md = checkfield(md,'fieldname','smb.tcIdx','NaN',1,'Inf',1,'values',[1,2]);
 			md = checkfield(md,'fieldname','smb.swIdx','NaN',1,'Inf',1,'values',[0,1]);
 			md = checkfield(md,'fieldname','smb.denIdx','NaN',1,'Inf',1,'values',[1,2,3,4,5,6,7]);
@@ -509,4 +519,5 @@
 			WriteData(fid,prefix,'object',self,'class','smb','fieldname','aIdx','format','Integer');
 			WriteData(fid,prefix,'object',self,'class','smb','fieldname','eIdx','format','Integer');
+			WriteData(fid,prefix,'object',self,'class','smb','fieldname','tcIdx','format','Integer');
 			WriteData(fid,prefix,'object',self,'class','smb','fieldname','swIdx','format','Integer');
 			WriteData(fid,prefix,'object',self,'class','smb','fieldname','denIdx','format','Integer');
Index: /issm/trunk-jpl/src/m/classes/SMBgemb.py
===================================================================
--- /issm/trunk-jpl/src/m/classes/SMBgemb.py	(revision 27235)
+++ /issm/trunk-jpl/src/m/classes/SMBgemb.py	(revision 27236)
@@ -79,4 +79,8 @@
         # 1: default value of 1, in areas with grain radius below teThresh
         # 2: default value of 1, in areas with grain radius below teThresh and areas of dry snow (not bare ice or wet) at the surface
+
+        self.tcIdx                   = np.nan    #method for calculating thermal conductivity (default is 1)
+        # 1: after Sturm et al, 1997
+        # 2: after Calonne et al., 2011 
 
         self.swIdx                  = np.nan    # apply all SW to top grid cell (0) or allow SW to penetrate surface (1) (default 0, if swIdx=1 and aIdx=2, function of effective radius (Brun et al., 1992) or else dependent on snow density (taken from Bassford, 2002)) 
@@ -207,4 +211,7 @@
             '1: default value of 1, in areas with grain radius below teThresh',
             '2: default value of 1, in areas with grain radius below teThresh and areas of dry snow (not bare ice or wet) at the surface']))
+        s += '{}\n'.format(fielddisplay(self, 'tcIdx', ['method for calculating thermal conductivity (default is 1)',
+            '1: after Sturm et al, 1997',
+            '2: after Calonne et al., 2011']))
 
         # Snow properties init
@@ -330,4 +337,5 @@
         self.aIdx = 1
         self.eIdx = 1
+        self.tcIdx = 1
         self.swIdx = 0 
         self.denIdx = 2
@@ -417,4 +425,5 @@
         md = checkfield(md, 'fieldname', 'smb.aIdx', 'NaN', 1, 'Inf', 1, 'values', [0, 1, 2, 3, 4])
         md = checkfield(md, 'fieldname', 'smb.eIdx', 'NaN', 1, 'Inf', 1, 'values', [0, 1, 2])
+        md = checkfield(md, 'fieldname', 'smb.tcIdx', 'NaN', 1, 'Inf', 1, 'values', [1, 2])
         md = checkfield(md, 'fieldname', 'smb.swIdx', 'NaN', 1, 'Inf', 1, 'values', [0, 1])
         md = checkfield(md, 'fieldname', 'smb.denIdx', 'NaN', 1, 'Inf', 1, 'values', [1, 2, 3, 4, 5, 6, 7])
@@ -496,4 +505,5 @@
         WriteData(fid, prefix, 'object', self, 'class', 'smb', 'fieldname', 'aIdx', 'format', 'Integer')
         WriteData(fid, prefix, 'object', self, 'class', 'smb', 'fieldname', 'eIdx', 'format', 'Integer')
+        WriteData(fid, prefix, 'object', self, 'class', 'smb', 'fieldname', 'tcIdx', 'format', 'Integer')
         WriteData(fid, prefix, 'object', self, 'class', 'smb', 'fieldname', 'swIdx', 'format', 'Integer')
         WriteData(fid, prefix, 'object', self, 'class', 'smb', 'fieldname', 'denIdx', 'format', 'Integer')