A model which translates snow depth observations to snow water equivalents

The HS2SWE model is based on similar principles as the delta.snow model. It is described in the following publication: Magnusson, J., B. Cluzet., L. Quéno, R. Mott, M. Oberrauch, G. Mazzotti, C. Marty, T. Jonas; 2025; Evaluating methods to estimate the water equivalent of new snow from daily snow depth recordings; Cold Regions Science and Technology, 233; 10.1016/j.coldregions.2025.104435.

Usage

hs2swe(
  data,
  RhoNew = 113.7,
  RhoMax = 571.6,
  SnoTemp = -0,
  Visc = 60510000,
  DQMultInc = 0.1,
  DQMultMax = 5,
  HsAcc = 2,
  c1 = 2.8e-06,
  c2 = 0.042,
  c3 = 0.046,
  c4 = 0.081,
  c5 = 0.018,
  g = 9.81,
  dt = 86400
)

Arguments

data

A data.frame with at least two columns named date and hs. They should contain date and corresponding daily observations of snow depth \(hs \ge 0\) measured at one site. The unit must be meters (m). No gaps or NA are allowed. Dates must be either of class `character`, `Date` or `POSIXct` and given in the format YYYY-MM-DD.

RhoNew

The density of new snow in kg/m³. Default is 113.7 kg/m³.

RhoMax

The maximum density of snow in kg/m³. Default is 571.6 kg/m³.

SnoTemp

The temperature of the snow in °C. Default is -0.000 °C.

Visc

The viscosity of the snow in kg/m²/s. Default is 6.051e7 kg/m²/s.

DQMultInc

The increment of the densification rate. Default is 0.1.

DQMultMax

The maximum densification rate. Default is 5.

HsAcc

The threshold for new snow fall in cm. Default is 2 cm.

c1

The first coefficient for the densification rate. Default is 2.8e-6.

c2

The second coefficient for the densification rate. Default is 0.042.

c3

The third coefficient for the densification rate. Default is 0.046.

c4

The fourth coefficient for the densification rate. Default is 0.081.

c5

The fifth coefficient for the densification rate. Default is 0.018.

g

The gravitational acceleration in m/s². Default is 9.81 m/s².

dt

The time step in seconds. Default is 86400 seconds (1 day).

Value

A numeric vector of simulated SWE in mm.

Details

The model is also available as matlab function, python package or as R function that accepts a slightly different input from https://github.com/oshd-slf/HS2SWE

Examples

data(hsdata, package = "nixmass")

swe_deltasnow <- swe.delta.snow(hsdata)
swe_hs2swe <- hs2swe(hsdata)
plot(seq_along(hsdata$date), swe_deltasnow, type = "l", ylab = "SWE (mm) / hs (cm)", xlab = "day")
lines(seq_along(hsdata$date), swe_hs2swe, type = "l", col = "red")
lines(seq_along(hsdata$date), hsdata$hs * 100, type = "l", lty = 2, col = "grey30")
legend("topleft", legend = c("deltaSNOW", "HS2SWE", "HS"),
 col = c("black", "red", "grey30"), lty = c(1, 1, 2))