Natural Hazards

Review of Natural Hazard

The following is a list of natural events and relative existing models, procedures, or works. Please feed the list with other phenomena and resources.

Rockfall

Rockcone implement a quick and low-cost determination of areas endangered by rockfalls following an heuristic approach: a block tarting from a source will travel down the slope and stop at the intersection point of the topography with a so called energy line drawn from the source point and making an angle φ with horizontal.

Sass3d is 3D rock fall model accounting for flying routine (air trajectory), rebound routine (energy loss) & rolling routine (equivalent sliding approach).

Avalanche

missing, existing slope instability zonation applications (Raghavan et al. 2004)

Debris Flow

• r.dfw

Is an empirical model to estimate areas involved by the diffusion of the debris. It uses a Monte Carlo approach based on wolkers. The outputs are raster estimates of velocity, sedimentation height, and number of random walk. The Perla velocity model is applied.

Flood

• r.sim.water - Overland flow hydrologic simulation using path sampling method (SIMWE).
• HydroFOSS - a GIS embedded approach for Free & Open Source Hydrological modeling.
• r.topkapi - ?
• r.water.fea - Finite element analysis program for hydrologic simulations (GRASS 4 only, document)
• r.hydro.CASC2D (in GIPE)
• r.inund.fluv - allows to obtain a fluvial potentially inundation map given a high-resolution DTM of the area surrounding the river and a water surface profile calculated through an 1-D hydrodynamic model.
• r.damflood - Estimate the area potentially inundated in case of dam break using the Shallow Water Equation (swe.h ANSI C library)
• r.traveltime - computes the travel time of surface runoff to an outlet

Landslide

• missing flow models
• exists slope instability zonation (Avalanche risk management using GRASS GIS. Marco Ciolli and Paolo Zatelli, 2002, Geomatic Workbooks)

Erosion

• Erosion/deposition modeling in complex terrain using GIS, Tutorial, Helena Mitasova.

Tsunami

This script implements the metodology described in MAPPE DI INONDAZIONE DOVUTE A TSUNAMI MEDIANTE IL GIS GRASS: APPLICAZIONE ALL'ISOLA DI ST. LUCIA, CARAIBI, Cannata M, B. Federici, M. Molinari, 2006, PDF.

This work shows the application and the validation of a procedure in GRASS to realize tsunami inundation maps based on the morphological characteristics, the vegetation and the settlements of the analyzed coast. Such a procedure, already illustrated in the VII GRASS Italian Users Meeting, and then improved, allow the estimation of the maximum vertical height of the tsunami waves hitting the coast (run-up) and the subsequent diffusion over the inland areas, as a function of the morphology, the vegetation, and the urbanization of the coastal area. The model, already successfully applied for the ligurian coast, has to be tested in different areas in order to validate a global applicability. For this reason the selected case study was the Caribbean island of St. Lucia. Based on elevation data, land-use, coast-line, observations, and studies, the methodology was applied and the inundation maps for three different event was estimated. The results were compared historical data and other estimates, verifying the general validity of the method.

Wildfire

• The wildfire spread simulation in GRASS is done using three modules:
• r.ros (for wildfire spread simulation) - Generates three, or four raster map layers showing 1) the base (perpendicular) rate of spread (ROS), 2) the maximum (forward) ROS, 3) the direction of the maximum ROS, and optionally 4) the maximum potential spotting distance. See also How to create parameters to run r.ros.
• r.spread - Simulates elliptically anisotropic spread on a graphics window and generates a raster map of the cumulative time of spread, given raster maps containing the rates of spread (ROS), the ROS directions and the spread origins. It optionally produces raster maps to contain backlink UTM coordinates for tracing spread paths.
• r.spreadpath - Recursively traces the least cost path backwards to cells from which the cumulative cost was determined.

Earthquakes

• Recent Earthquakes: [<- Link is broken] map of earthquakes that have occurred in the last 7 days. A new image is generated every three hours by a GRASS batch job running on a headless server which fetches data from the USGS and creates a logarithmic bubble plot. The scripts that run this can be found in the "promo" tutorials section of the GRASS SVN code repository. Some additional real-time maps centered on New Zealand can be found there too.

References

• Cannata M., Marzocchi R., and Molinari M.E. Modeling of landslide–generated tsunami with grass. Transaction in GIS 16(2) , page 191–214, 2012
• Cannata M. and Marzocchi R. Two dimensional dam break flooding simulation - a gis embedded approach. Natural Hazards 61(3) , pages 1143–1159, 2012
• Di Leo M., Manfreda S., Fiorentino M., An automated procedure for the detection of flood prone areas: r.hazard.flood, Geomatics Workbooks n.10, 2011. (PDF)
• Manfreda S., Di Leo M., Sole A., Detection of Flood Prone Areas using Digital Elevation Models, Journal of Hydrologic Engineering, (10.1061/(ASCE)HE.1943-5584.0000367), 2011.
• Marzocchi R., Federici B., Cannata M., Cosso T., and Syriou A. The contribution of gis in flood mapping. two approaches using open source grass gis software. Applied geomatics , 2014
• K. Suprit, Aravind Kalla and V. Vijith. A GRASS-GIS-Based Methodology for Flash Flood Risk Assessment in Goa, 2010. (PDF)