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