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3.2.9. SUEWS_Snow.txt

SUEWS_Snow.txt specifies the characteristics for snow surfaces when SnowUse=1 in RunControl.nml. If the snow part of the model is not run, fill this table with ‘-999’ except for the first (Code) column and set SnowUse=0 in RunControl.nml. For a detailed description of the variables, see Järvi et al. (2014) [Järvi et al., 2014].

No.	Column Name	Use	Description
1.0	Code	L	Code linking to a corresponding look-up table.
2.0	RadMeltFactor	MU	Hourly radiation melt factor of snow [mm W-1 h-1]
3.0	TempMeltFactor	MU	Hourly temperature melt factor of snow [mm K-1 h-1]
4.0	AlbedoMin	MU	Effective surface albedo (middle of the day value) for wintertime (not including snow).
5.0	AlbedoMax	MU	Effective surface albedo (middle of the day value) for summertime.
6.0	Emissivity	MU	Effective surface emissivity.
7.0	tau_a	MD	Time constant for snow albedo aging in cold snow [-]
8.0	tau_f	MD	Time constant for snow albedo aging in melting snow [-]
9.0	PrecipLimAlb	MD	Limit for hourly precipitation when the ground is fully covered with snow [mm]
10.0	SnowDensMin	MD	Fresh snow density [kg m-3]
11.0	SnowDensMax	MD	Maximum snow density [kg m-3]
12.0	tau_r	MD	Time constant for snow density ageing [-]
13.0	CRWMin	MD	Minimum water holding capacity of snow [mm]
14.0	CRWMax	MD	Maximum water holding capacity of snow [mm]
15.0	PrecipLimSnow	MD	Temperature limit when precipitation falls as snow [°C]
16.0	OHMCode_SummerWet	L	Code for OHM coefficients to use for this surface during wet conditions in summer, linking to SUEWS_OHMCoefficients.txt.
17.0	OHMCode_SummerDry	L	Code for OHM coefficients to use for this surface during dry conditions in summer, linking to SUEWS_OHMCoefficients.txt.
18.0	OHMCode_WinterWet	L	Code for OHM coefficients to use for this surface during wet conditions in winter, linking to SUEWS_OHMCoefficients.txt.
19.0	OHMCode_WinterDry	L	Code for OHM coefficients to use for this surface during dry conditions in winter, linking to SUEWS_OHMCoefficients.txt.
20.0	OHMThresh_SW	MD	Temperature threshold determining whether summer/winter OHM coefficients are applied [°C]
21.0	OHMThresh_WD	MD	Soil moisture threshold determining whether wet/dry OHM coefficients are applied [-]
22.0	ESTMCode	L	Code for ESTM coefficients linking to SUEWS_ESTMCoefficients.txt
23.0	AnOHM_Cp	MU	Volumetric heat capacity for this surface to use in AnOHM [J m-3]
24.0	AnOHM_Kk	MU	Thermal conductivity for this surface to use in AnOHM [W m K-1]
25.0	AnOHM_Ch	MU	Bulk transfer coefficient for this surface to use in AnOHM [-]

An example SUEWS_Snow.txt can be found below:

1     	 2             	 3              	 4         	 5         	 6          	 7     	 8     	 9            	 10          	 11          	 12    	 13     	 14     	 15            	 16                	 17                	 18                	 19                	 20           	 21           	 22       	 23       	 24       	 25
Code  	 RadMeltFactor 	 TempMeltFactor 	 AlbedoMin 	 AlbedoMax 	 Emissivity 	 tau_a 	 tau_f 	 PrecipLimAlb 	 SnowDensMin 	 SnowDensMax 	 tau_r 	 CRWMin 	 CRWMax 	 PrecipLimSnow 	 OHMCode_SummerWet 	 OHMCode_SummerDry 	 OHMCode_WinterWet 	 OHMCode_WinterDry 	 OHMThresh_SW 	 OHMThresh_WD 	 ESTMCode 	 AnOHM_Cp 	 AnOHM_Kk 	 AnOHM_Ch
99999 	 -999          	 -999           	 -999      	 -999      	 -999       	 -999  	 -999  	 -999         	 -999        	 -999        	 -999  	 -999   	 -999   	 -999          	 61                	 61                	 61                	 61                	 10           	 0.9          	 99999    	 100000   	 1.2      	 4        	 !
1     	 0.0016        	 0.12           	 0.18      	 0.85      	 0.99       	 0.018 	 0.11  	 2            	 100         	 400         	 0.043 	 0.05   	 0.2    	 2.2           	 61                	 61                	 61                	 61                	 10           	 0.9          	 61       	 100000   	 1.2      	 4        	 ! 	 Helsinki   (HCW   added   0.99   for      emissivity) 	 Jarvi   et   al.   (2014)
550   	 0.001         	 0.14           	 0.18      	 0.8       	 0.99       	 0.01  	 0.1   	 2            	 100         	 450         	 0.02  	 0.03   	 0.1    	 2.2           	 61                	 61                	 61                	 61                	 10           	 0.9          	 61       	 100000   	 1.2      	 4        	 ! 	 Swindon  	 Ward   et      al.    (2013)
660   	 0.001         	 0.14           	 0.18      	 0.8       	 0.99       	 0.01  	 0.1   	 2            	 100         	 450         	 0.02  	 0.03   	 0.1    	 2.2           	 61                	 61                	 61                	 61                	 10           	 0.9          	 61       	 100000   	 1.2      	 4        	 ! 	 London
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