SnowMelt: Snow Melt Calculator

In EcoHydRology: A Community Modeling Foundation for Eco-Hydrology

Description

Calculates snow pack accumulation and melt

Usage

SnowMelt(Date, precip_mm, Tmax_C, Tmin_C, lat_deg, slope = 0,
 aspect = 0, tempHt = 1, windHt = 2, groundAlbedo = 0.25,
 SurfEmissiv = 0.95, windSp = 2, forest = 0, startingSnowDepth_m = 0,
 startingSnowDensity_kg_m3=450)

Arguments

Date	Vector of dates (class Date or character) in this format: Y-m-d
precip_mm	Precipitation in mm
Tmax_C	Daily maximum temperature (degrees C)
Tmin_C	Daily minimum temperature (degrees C)
lat_deg	Degrees latitude
slope	Overall slope of area of interest
aspect	Aspect of the area of interest
tempHt	height of temperature measurements (m)
windHt	height of wind measurements (m)
groundAlbedo	Ground Albedo, 0-1 (-)
SurfEmissiv	Surface Emissivity, 0-1 (-)
windSp	Wind speed - either a vector of measured values or a single value of average wind speed for the site (m/s)
forest	Forest cover (shade) - use this only when determining snowmelt under a canopy, 0-1 (-)
startingSnowDepth_m	The depth of the snow pack initially (m)
startingSnowDensity_kg_m3	The density of snow on the ground on the first day (kg/m3)

Value

This will return a 10 column data frame with nrow = length of input weather data. Column names are : Date, MaxT_C, MinT_C, Precip_mm, Rain_mm, SnowfallWatEq_mm, SnowMelt_mm, NewSnow_m, SnowDepth_m, SnowWaterEq_mm

Warning

This function cannot handle NA values in input, and can only be run for continuous daily data. For data-sets missing values, run discontinuous segments separately.

Author(s)

Josephine Archibald, M. Todd Walter

References

Walter, M.T. , E.S. Brooks, D.K. McCool, L.G. King, M. Molnau, J. Boll. 2005. Process-based snowmelt modeling: Does it require more input data than temperature-index modeling? Journal of Hydrology 300(1-4): 65-75

Examples

##  
data(OwascoInlet)
sm <- SnowMelt(Date=OwascoInlet$date, precip_mm=OwascoInlet$P_mm,
 Tmax_C=OwascoInlet$Tmax_C, Tmin_C=OwascoInlet$Tmin_C, lat_deg=42)
summary(sm)

Example output

Loading required package: operators

Attaching package: 'operators'

The following objects are masked from 'package:base':

    options, strrep

Loading required package: topmodel
Loading required package: DEoptim
Loading required package: parallel

DEoptim package
Differential Evolution algorithm in R
Authors: D. Ardia, K. Mullen, B. Peterson and J. Ulrich

Loading required package: XML
Warning message:
In Solar(lat = lat, Jday = JDay[1], Tx = Tmax_C[1], Tn = Tmin_C[1],  :
  In Solar(): Input latitude units are not specified and assumed to be radians
      Date                MaxT_C            MinT_C          Precip_mm      
 Min.   :2009-04-22   Min.   :-12.220   Min.   :-26.110   Min.   :  0.000  
 1st Qu.:2009-11-29   1st Qu.:  8.193   1st Qu.: -1.670   1st Qu.:  0.000  
 Median :2010-07-09   Median : 18.330   Median :  6.670   Median :  0.000  
 Mean   :2010-07-17   Mean   : 15.977   Mean   :  5.059   Mean   :  3.121  
 3rd Qu.:2011-03-16   3rd Qu.: 25.000   3rd Qu.: 12.220   3rd Qu.:  2.540  
 Max.   :2011-10-26   Max.   : 36.670   Max.   : 23.330   Max.   :112.522  
    Rain_mm        SnowfallWatEq_mm   SnowMelt_mm        NewSnow_m       
 Min.   :  0.000   Min.   : 0.0000   Min.   : 0.0000   Min.   :0.000000  
 1st Qu.:  0.000   1st Qu.: 0.0000   1st Qu.: 0.0000   1st Qu.:0.000000  
 Median :  0.000   Median : 0.0000   Median : 0.0000   Median :0.000000  
 Mean   :  2.969   Mean   : 0.1525   Mean   : 0.1525   Mean   :0.001898  
 3rd Qu.:  2.095   3rd Qu.: 0.0000   3rd Qu.: 0.0000   3rd Qu.:0.000000  
 Max.   :112.522   Max.   :15.2400   Max.   :40.2857   Max.   :0.152327  
  SnowDepth_m     SnowWaterEq_mm  
 Min.   :0.0000   Min.   : 0.000  
 1st Qu.:0.0000   1st Qu.: 0.000  
 Median :0.0000   Median : 0.000  
 Mean   :0.0124   Mean   : 2.702  
 3rd Qu.:0.0000   3rd Qu.: 0.000  
 Max.   :0.2585   Max.   :57.201  

EcoHydRology documentation built on May 2, 2019, 8:28 a.m.