SNOWPACK 3.7.0
Metamorphism.cc File Reference

This module contains the snow metamorphism routines of the SLF one-dimensional snowpack model
It represents a truly international research effort: Dr. Bob "Borolo" Brown of montana state university (USA) provided a lot of the motivation and low temperature gradient micro-structure physics; Dr. Michael provided project leadership, a sense of the practical and more importantly, the link to the avalanche warning group, i.e. he told everybody what to do; Dr. Pramod Sataywali (SASE, INDIA) came up with the high temperature gradient micro-structure routines; Dr. Perry Bartelt wrote the code and integrated it into a very sensible continuum mechanics model that works pretty well. More...

#include <cstddef>
#include <snowpack/snowpackCore/Metamorphism.h>
#include <snowpack/Constants.h>
#include <snowpack/Utils.h>
#include <snowpack/snowpackCore/Snowpack.h>

Functions

Thresholds for wind slab formation
static std::string get_model (const SnowpackConfig &cfg)
 
static double get_sn_dt (const SnowpackConfig &cfg)
 
static double get_nsgs (const SnowpackConfig &cfg)
 

Detailed Description

This module contains the snow metamorphism routines of the SLF one-dimensional snowpack model
It represents a truly international research effort: Dr. Bob "Borolo" Brown of montana state university (USA) provided a lot of the motivation and low temperature gradient micro-structure physics; Dr. Michael provided project leadership, a sense of the practical and more importantly, the link to the avalanche warning group, i.e. he told everybody what to do; Dr. Pramod Sataywali (SASE, INDIA) came up with the high temperature gradient micro-structure routines; Dr. Perry Bartelt wrote the code and integrated it into a very sensible continuum mechanics model that works pretty well.

Definition of some of the essential variables:

PRIMARY micro-structure parameters computed by the Metamorphism routine:

  • rb : bond radius in [mm]
  • rg : grain radius in [mm]
  • dd : snow dendricity (=0 old snow; =1 new snow)
  • sp : snow sphericity (=0 faceted; =1 rounded)
  • mk : microstructure marker:
    • 0 dendritic snow or neither faceted nor rounded
    • 1 reached a sp of 0
    • 2 reached a sp of 1
    • 3 Surface Hoar SH
    • 4 Graupel PPgp
    • 5 Not implemented yet --> thin crusts
    • 6 Technical Snow
    • 7 Glacier ice
    • 8 Ice layer IFil
    • 9 Pure water on top of snowpack, soil, or road
    • mk < 10, mk=mk+10 : first complete wetting
    • mk < 20, mk=mk+10 : first melt-freeze cycle completed
    • mk / 100 >= 1 : tagged snow layer
    • mk / 1000 >= 9 : marked reference level to reference height of wind and meteo values, as well as measured snow height

SECONDARY micro-structure parameters computed by Metamorphism routine:

  • N3 : coordination number (1)

SECONDARY micro-structure parameters computed by routines found in Laws_sn.c:

  • keff : effective conductivity (W m-1 K-1)
  • E : modulus of elasticity (Pa)
  • eta : viscosity (Pa s)

These are the variables needed to compute these values of the ElementData class within the snowStation class:

  • theta[ICE] : volumetric ice content (1)
  • theta[WATER] : volumetric water (1)
  • Te : temperature (K)
  • dTdZ : temperature gradient (K m-1)
  • dPdZ : vapor pressure gradient (bar m-1)
  • Rho : bulk density (kg m-3)
  • S : overburden stress (Pa)

The french metamorphism routines were written in November 1995 by Perry Bartelt and Martin Schneebeli. They were first used in the 2d snowpack code haefeli.

Function Documentation

◆ get_model()

static std::string get_model ( const SnowpackConfig &  cfg)
static

◆ get_nsgs()

static double get_nsgs ( const SnowpackConfig &  cfg)
static

◆ get_sn_dt()

static double get_sn_dt ( const SnowpackConfig &  cfg)
static