Canton du Valais, Service des forêts et du paysage (SFP), section des dangers naturels

Kanton Graubünden, Amt für Wald Graubünden, Naturgefahren

Regione Valle d‘Aosta, Dipartimento Difesa del Suolo e Risorse Idriche

Regione Piemonte, Direzione Opere pubbliche, Difesa del Suolo, Economia Montana e Foreste

Regione Lombardia, Agenzia Regionale per la Protezione dell‘Ambiente

Arpa Lombardia, Direzione Generale Protezione Civile, Prevenzione e Polizia Locale

Arpa Piemonte, Agenzia Regionale per la Protezione Ambientale

SLF, WSL-Institut für Schnee- und Lawinenforschung SLF

http://www.progettostrada.net/

AINEVA, Associazione Interregionale Neve e Valanghe

How snow cover properties influence avalanche dynamics

Walter Steinkogler1,2

Jochen Veitinger1,3, Betty Sovilla1, Michael Lehning1,2 1WSL-Institut für Schnee- und Lawinenforschung SLF

2CRYOS, Faculté de L’environnement naturel, architectural et construit , EPFL, Lausanne

3Geographisches Institut, Universität Zürich

Content

The MOTIVATION

The MODELS (Alpine3D/SNOWPACK/RAMMS)

The RESULTS for winter 2012/13 in VDLS

The POSSIBLE APPLICATIONS

The (far) FUTURE

Motivation – practical view

Roads Ski slopes Railway

Avalanches directly affect safety of many mountain communities

Motivation – scientific view

Snow cover properties influence…

... the development of flow regimes and granulation

Key parameters: temperature, density, moisture content, granular size

Key parameters: erosion depth density

… the mass balance by defining the potential of entrainment of additional mass

Motivation – scientific view

Alpine3D / SNOWPACK RAMMS

- „Rapid mass movements“ - 3D avalanche dynamics model

Used for hazard mapping in Switzerland

Recent large improvements in modelling of snow distribution in alpine terrain

Missing link: Influence of snow properties on flow dynamics

- spatially distributed (surface), three- dimensional (atmospheric) model

Motivation

What can be used by practitioners directly and indirectly?!

Research Practitioneer

!!! Your input is needed Discussion/workshop !!!

Differences in mobility

Example 1 Example 2

- 2 avalanches from VDLS dataset

- Similar initial conditions (release area) but very different ‚mobility‘

Differences in mobility

Deposition structures:

Example 1: fan-shaped deposition, uniform granule distribution

Example 2: Flow-fingers, strong levee formation and big granules

Temperature granulation mobility

- 2 avalanches from VDLS dataset

- Similar initial conditions (release area) but very different ‚mobility‘

Example 1 Example 2

Alpine3D

Alpine3D spatially distributed (surface), 3D (atmospheric) model

Input: multiple automatic weather stations

Modeling: supplementary data spatial distribution of snow and its properties

Grid: with 25 m cell resolution

Alpine3D - HS

Practitioneer: Is the absolute snow height important in my area or avalanche path (roughness, release area size, …)??

Alpine3D –dHS24

2012 12 04 2012 12 18 2013 01 11 2013 02 02

Practitioneer: Is the 24 hour new snow height important in my area (small vs. extreme avalanches) ??

Alpine3D – TS40

Practitioneer: Is the snow temperature important in my avalanche path (cold/warm avalanches, cold in release and warm in the runout, …)??

Alpine3D – TS40

2013 01 30 2013 01 31 2013 02 01 2013 02 02

Alpine3D/SNOWPACK

A

D

C

Snow cover model SNOWPACK allows full snow pack information at every grid cell

Temperature profile at selected points along avalanche path

B

T(de) T(de) T(de) T(de)

#816 -8.0°C / 17.6°F

(2 m) -6.6°C / 20.1°F

(1.5 m) -3.3°C / 26.1°F

(1 m) -3.1°C / 26.4°F

(1.5 m)

#917 -5.5°C / 22.1°F

(2m) -4.9°C / 23.2°F

(1m) -1.1°C / 30.2°F

(1.5 m) -0.8°C / 30.6°F

(1.3 m)

A

D

C

B

2013 02 02

2012 12 04

Alpine3D – TS40 & Radar

Snow temperature modeled with Alpine3D

Avalanche front velocity measured with Radar

For example picture see Sovilla-Intro.pdf

For example picture see Sovilla-Intro.pdf

Applications: RAMMS

- Including temperature effects in RAMMS

Alpine3D

RAMMS

RAMMS

- Allows coupling to snow cover models (Alpin3D)

- Especially important for non-extreme avalanches

(Vera et. al., Thermal temperature in avalanche flow; ISSW 2012)

SNOWPACK

The (far) future

Alpine3D

RAMMS

Further developing and combining of avalanche & snow cover models - Especially for non-extreme avalanches - From ‚quasi-real time‘ to forecasting - Forecasting for larger and data sparse regions - Regional hazard mapping

Research Practitioneer

What does the practitioneer need???

Appendix

APPENDIX

Alpine3D / SNOWPACK

- Wet snow avalanche activity?

- Accurate enough for (rough) stratigraphy? Yes for dynamics, but also for LWD?

Full SNOWPACK output at every grid cell.

VDS 1 FMCW B FMCW A FMCW C

VDS 1

FMCW C

FMCW B

FMCW A

Alpine3D/SNOWPACK

VDS 1

FMCW C

FMCW B

Snow cover model SNOWPACK allows full snow pack information at every grid cell

Temperature profile at selected points along avalanche path

FMCW A

T(de) T(de) T(de) T(de)

#816 -8.0°C / 17.6°F

(2 m) -6.6°C / 20.1°F

(1.5 m) -3.3°C / 26.1°F

(1 m) -3.1°C / 26.4°F

(1.5 m)

#917 -5.5°C / 22.1°F

(2m) -4.9°C / 23.2°F

(1m) -1.1°C / 30.2°F

(1.5 m) -0.8°C / 30.6°F

(1.3 m)

VDS 1

FMCW B

FMCW A

FMCW C