Note

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4.2.9. 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) [Leena2014].

No.	Column Name	Use	Description
1	Code	L	Code linking to a corresponding look-up table.
2	RadMeltFactor	MU	Hourly radiation melt factor of snow [mm W-1 h-1]
3	TempMeltFactor	MU	Hourly temperature melt factor of snow [mm K-1 h-1]
4	AlbedoMin	MU	Effective surface albedo (middle of the day value) for wintertime (not including snow).
5	AlbedoMax	MU	Effective surface albedo (middle of the day value) for summertime.
6	Emissivity	MU	Effective surface emissivity.
7	tau_a	MD	Time constant for snow albedo aging in cold snow [-]
8	tau_f	MD	Time constant for snow albedo aging in melting snow [-]
9	PrecipLimAlb	MD	Limit for hourly precipitation when the ground is fully covered with snow [mm]
10	SnowDensMin	MD	Fresh snow density [kg m-3]
11	SnowDensMax	MD	Maximum snow density [kg m-3]
12	tau_r	MD	Time constant for snow density ageing [-]
13	CRWMin	MD	Minimum water holding capacity of snow [mm]
14	CRWMax	MD	Maximum water holding capacity of snow [mm]
15	PrecipLimSnow	MD	Temperature limit when precipitation falls as snow [°C]
16	OHMCode_SummerWet	L	Code for OHM coefficients to use for this surface during wet conditions in summer, linking to SUEWS_OHMCoefficients.txt.
17	OHMCode_SummerDry	L	Code for OHM coefficients to use for this surface during dry conditions in summer, linking to SUEWS_OHMCoefficients.txt.
18	OHMCode_WinterWet	L	Code for OHM coefficients to use for this surface during wet conditions in winter, linking to SUEWS_OHMCoefficients.txt.
19	OHMCode_WinterDry	L	Code for OHM coefficients to use for this surface during dry conditions in winter, linking to SUEWS_OHMCoefficients.txt.
20	OHMThresh_SW	MD	Temperature threshold determining whether summer/winter OHM coefficients are applied [°C]
21	OHMThresh_WD	MD	Soil moisture threshold determining whether wet/dry OHM coefficients are applied [-]
22	ESTMCode	L	Code for ESTM coefficients linking to SUEWS_ESTMCoefficients.txt
23	AnOHM_Cp	MU	Volumetric heat capacity for this surface to use in AnOHM [J m-3]
24	AnOHM_Kk	MU	Thermal conductivity for this surface to use in AnOHM [W m K-1]
25	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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