landslide early warning - czech republic 2009

Cartography and Geoinformatics for Early Warning and Emergency Management: Towards Better Solutions – Prague , 19-22 January 2009Schillinger, Strauch &Gutiérrrez: Using satellite based rainfall estimates for early warning on landslides and inundations in Central America

Using satellite based rainfall estimates for early warning on landslides and inundations

in Central America

Steffen Schillinger Bundesanstalt für Geowissenschaften und Rohstoffe (BGR), Hannover, Germany,

Project on Georisks in Central America, with INETER, Managua Nicaragua Email: [email protected]

Wilfried Strauch on leave from Instituto Nicaraguense de Estudios Territoriales (INETER),Recent Address: Project on Georisks in Central America, BGR-INETERINETER, Managua, Nicaragua, Email: [email protected]

Vladimir Gutiérrez Instituto Nicaragüense de Estudios Territoriales (INETER), Managua, Nicaragua,

Recent address: Technical University of Madrid (UPM), Email: [email protected]

Hurricane Mitch Landslide at Casita volcano Inundations(Oct. 1998) (triggered by heavy rains, 2000 killed) (1700mm rain in 5 days)

Photos taken from the newspaper El Nuevo Diario, Managua, Nicaragua, November 1, 1998

Nicaragua – Lakes and Volcanoes


Landslide Hazard and Risk in Central America

LandslideHazard

Riskdeath/year/km2

Population density

From: Nadim, F., O. Kjekstad, P. Peduzzi, C. Herold, C. Jaedicke

(2006), Global landslide and avalanche, hotspots, J. Landslides,

3(2), 159–173, doi:10.1007/ s10346-006-0036-1.


From: Devoli , Morales & Høeg (2006) Historical landslides in Nicaragua—collection and analysis of data, Landslides, DOI 10.1007/s10346-006-0048-x

Trigger phenomena

Type of landslide

Occurrence over the year Damage caused

Characterization of 135 historical landslides in Nicaragua, 1800-1990

main hurricane and raining season


Strong and/or long lasting rains trigger landslides

Extreme example: Hurricane Mitch, Nicaragua, October 30, 1998

“Normal” example: Landslides due to tropical storms during rainy season

2 km

15 km

2 villages annihilated

More than 2000 people died

Honduras, Sept.2008


From: Devoli , Strauch , Chávez , Høeg (2007) A landslide database for Nicaragua: a tool for landslide-hazard management, Landslides DOI 10.1007/s10346-006-0074-8

Recent Landslides Inventory of Nicaragua

About 17,000 events

Most of these events occurred during hurricane Mitch in 1998 !


Met station -

Precipitation dataMonitoring

software

-

Verification

Field visits or reports

from local population

In some cases - real time verification possible

with seismic stations near the gullies

Mapping of impact

If precipitation > trigger level

-> Alert

Solution works but…

Problem:

In case of local rains -

data of met station are

representative only for a

small area. e.g. for one side

of a volcano. Too many

stations would be necessary

for an operative system

First Trial: Pilot project INETER-NGI, 2000-2004 Early Warning with meteorological stations, in volcanoes


PRO: -Near real time data

CON: -Station density is far too low to permit

reliable detection of high precipitation

in areas under landslide risk

There are no met radars in Nicaragua or Central America

Landslide map

Nicaraguan Meteorological Network


Solution :Hydroestimator -Precipitation estimate from GOES Met satellite

• NOAA/NESDIS calculates twice per hour precipitation estimates

• Precipitation is determined in near real time for 4x4 km pixels

• These data are available from: ftp://www.orbit.nesdis.noaa.gov/pub/smcd/emb/f_f/hydroest/grads/centralamerica

• Several authors have investigated the usefulness of the method for landslide early warning


The precipitation rates were obtained

from a fit between instantaneous radar

derived rainfall estimates and satellite

measurements of IR brightness

temperatures at cloud top.

The relationship has been computed

using 4-Km resolution pairs of GOES-8 IR

images and collocated instantaneous

radar rainfall estimates from the US

operational network of 5 and 10 cm radar

(WSR-57S, WSR-74C, WSR-88D) in the

central Great Plains and the areas

adjacent to the Gulf of Mexico.

Background of Hydroestimator:Relation between upper cloud temperature from GOES IR images and precipitation rate

The result of the comparison between the mean radar-derived estimates for each one

degree temperature intervals from 195 K to 260 K is shown in the figure.

From: Vicente, G.A. Scofield R. A. and Menzel, W.P. (1998) The Operational GOES Infrared Rainfall Estimation Technique, edition of the

Bulletin of American Meteorological Society, September 1998


“The satellite estimates showed that the heaviest rainfall occurred October 31 when outer convective bands from Mitch interacted and merged with the orographic produced convectionthat was already present in northwest Nicaragua. Accumulation of 3-day totals indicates that the heaviest rainsoccurred over Nicaragua with precipitation amounts maximum of 1400 mm (55 inches).”

From: Ferraro, R., G. A. Vicente, M. Ba, A. Gruber, R. Scofield, Q. Li and R. Weldon (1999) Satellite Techniques Yield Insight into Devastating Rainfall from Hurricane Mitch. EOS, Transaction, AGU, Vol. 80, No. 43, 10/26/1999, 512-514.

Application of Hydroestimator to Hurricane Mitch data

Location of Casita Volcano

– Disaster on October 30, 1998

2000+ killed

Comparison with precipitation recorded by INETER met stations:

Chinandega 1,613 mmLeón 1 ,113mmMasatepe 663mm Managua 545mmRivas 495mm


Global rainfall intensity-duration curve for triggering landslides

From: Hong Y., Adler R.E., Huffmann G.J. (2007). Satellite Remote Sensing, for Global Landslide

Monitoring, Eos, Vol. 88, No. 37, 11 September 2007


Application : Generation of interactive precipitation maps (author: St. Schillinger)

Nesessary software: ArcGIS 9.3 y VS2008, ArcSDE, Arc server

Functions:

•Download hourly precipitation data from NESDIS/NOAA (in GrADS format); •Archive original data•Convert data to ESRI raster format; •Archive data in a raster catalogue of an ArcSDE geodatabase; •Calculate sums of 3, 6, 24 hours, 2, 3, 7 days •Archive results in standardized GeoTiff, PNG formats; •Get the online data from INETER´s Met Network•Create an interactive map for ArcGis Server with the precipitation rastersincluding met station data

•Publish interactive map with ArcGis Server

Development of applications for the use of Hydroestimator


Client Application – Selection of the rain accumulation period

www.georiesgos-ca.info


Client Application– Access to the data base of INETER´s met stations



Client Application–automatic classification of precipitation



Client Application– Obtain precipitation estimate for a certain site



Application: Early warning for landslide sites (author: W.Strauch)

Nesessary software: GrADS and other free software components

Functions:

•Download hourly precipitation data from NESDIS/NOAA (in GrADS format); •Archive original data•Determine precipitations for a list of landslide sites

for testing: (1) sites of known landslides in Nicaragua(2) sites of the Central American Volcanoes

•If accumulated precipitation surpasses a trigger level –-> generate an email message

•Send the email to a list of recipients•Generate precipitation maps in GIF format (local, national, regional)•Generate GIF animation of precipitation in the last 24 hours•Transfer GIF maps and animation to Web server for publication

Development of applications for the use of Hydroestimator


Regional GIF animation using

original NESDIS files

Local map with numeric precipitation values

Precipitation map for Nicaragua


Monitored landslide sites in Nicaragua

Example of alert message:

Alerta para Coordenadas: -87.0064 12.7017 Sitio: Mocorón, Municipio : Chinandega2008/09/29 04:00 Precipitación de 38.4 mm en 1 hora(s) sobrepasa el umbral de 10.5 mmAumenta la posibilidad de deslizamientos en la zona!

Example of output list of early warning application:

Long_W Lat_N Ubicación Municipio0 mm at -86.3092 11.9923 Carretera,_entrada_a_El_Crucero EL_CRUCERO0 mm at -86.3111 11.9634 Carretera_El_Crucero-San_Rafael EL_CRUCERO0 mm at -86.4757 11.9439 Comunidad_Las_Cañas VILLA_EL_CARMEN2 mm at -86.3514 12.2366 Peninsula_de_Chiltepe MATEARE2 mm at -86.3316 12.2492 Peninsula_de_Chiltepe_MATEARE0 mm at -86.9148 12.6795 El_Higueral CHINANDEGA9 mm at -86.9148 12.6795 San_Lucas CHINANDEGA38.4 mm at -87.0064 12.7017 Mocorón CHINANDEGA 7 mm at -87.0064 12.7017 Las_Rojas CHINANDEGA6 mm at -87.0064 12.7017 Las_Banderas CHINANDEGA5 mm at -87.0064 12.7017 La_Laguna CHINANDEGA0 mm at -87.0064 12.7017 San_Rafael CHINANDEGA

...

...


Central American active volcanoes monitored

At the moment the list contains one site per volcano. In future it will be extended to contain the different gullies of each volcano where landslides (lahars) are frequent.


Application of method during Hurricane Felix, September 2007

The hurricane was monitored with the

system while crossing Nicaragua. It was

observed that the precipitations in the

mountainous areas did not surpass the

levels to trigger landslides. Thus, it was

not necessary to declare high alert levels.


Application for Assessment of Flash flood in Matagalpa, October 17, 2007


Flash flood in the city of Matagalpa

17 october, 2007, 18:00 local time

7 killed

Inundation map

Sequence of precipitation images showing

the strong rain which caused the flooding


Results:

1. Satellite based precipitation monitoring for Central America in place;

2. Webmapping service for precipitation maps in place;

3. Experimental early warning system for selected sites in place;

4. Asessment of landslide and inundation occurrence carried out for some events.

Future plans:

1. Compilation of lists of landslide sites for each Central American country

and integration in the early warning procedure;

2. Investigation of landslide occurrence and corresponding precipitations;

3. Determination of local rainfall intensity-duration curves for triggering landslides

for different site classes (geology) in Central America;

4. Information and training to emergency commissions and local authorities

about the use of warning messages;

5. Development of early warning system on inundations.

Results and future plans


Thank You !

This work is developed in the frame of the projects “Mitigation of Georisks in Central America” with funding from the governments of Germany and Central American countries and “Early Warning of Landslides in Nicaragua “with funding from the Norwegian government. The specific tasks for this paper were carried out in cooperation beween BGR (Hannover,Germany) , INETER (Managua, Nicaragua), with support from NGI(Oslo, Norway).



landslide early warning - czech republic 2009

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