WILDFIRE RISK

MANAGEMENT ON LARGE

MEDITERRANEAN

LANDSCAPES

IV International Congress on Risks “Risks and Education”

University of Coimbra (Portugal), 23 to 26 of May, 2017.

Fermín J. Alcasena Urdíroz Universitat de Lleida

Alan A. Ager US Forest Service

John D. Bailey Oregon State University

Cristina Vega García Universitat de Lleida

Putting the Mediterranean fires into context

• Annually 48.6 thousand fires burn 447.8 thousand ha on

southern EU countries.

• Few large fires account for most of the burned area.

• Large fires overwhelm suppression capabilities, spread for

long distances and concentrate on simultaneity episodes.

• Climate change and rural exodus will likely enhance the

mega fire escalade.

• Increasing WUI areas represent a civil protection issue.

• Current total fire suppression policy, accidental

ignition prevention programs and scattered fuel

treatment projects alone are insufficient to mitigate

risk on fire-prone Mediterranean landscapes.

Introduction

We purpose a cohesive strategy for southern EU

• We adapted the US Cohesive Strategy to a large

Mediterranean landscape, and generated a set of municipality

level spatial priority maps for wildfire risk management.

Objectives

Fire

resilient

landscapes

Cultural

fire regime

restoration

Efficient and

effective fire

suppression

Fire adapted

human

communities

Fuel

treatments

on strategic

locations

Community

protection plans

on high

exposure WUI

Ignition

monitoring

and fire use

regulation

Focus

suppression on

high impact low

hazard events

Strategies

Goals

General frameworkMaterial and methods

Wildfire season

fire spread and

behavior

modeling

Residential

houses on WUI

areas

Historic ignition

locations

Wildfire hazard

Fire transmission

Wildfire exposure

Lightning

ignitions

PLANNING AREAS

Anthropic

ignitions

Fuel treatments

Anthropic ignition

prevention

Lightning fire

monitoring

Fire suppression

opportunities

Community

action plans

Risk causative factors Mitigation strategies

PRIORITY MAPS

Wildfire risk causative factors

Hazard: potential for loss given a fire event, related to fire intensity.

Exposure: juxtaposition of assets with fire behavior (wildfire

likelihood and intensity).

Transmission: potential to affect distant assets from ignited fires in a

given location.

Material and methods

high hazard

high

hazard

low

exposure

low transmission

high

transmission

high exposure

low

hazard

A case study on a large Mediterranean landscape

• We generated wildfire risk management maps for

Catalonia (32 thousand km2, north-eastern Spain).

• Annually some 580 fires burn ~ 11.3 thousand ha

• Using FConst MTT fire modeling program we replicated

10,000 wildfire seasons at 150 m resolution considering

extreme fire weather conditions to assess wildfire hazard,

exposure and transmission to human communities.

• Historic ignitions (1983 to 2014) were used to identify

anthropic and lightning fire source prevalence areas.

• Municipality boundaries where used as Planning Areas.

• Priorities were classified into High (H), Moderate (M),

low (L) and very low (VL).

Material and methods

Fire modeling on large heterogeneous landscapes

Material and methods

(A)

(A) (C)(B) (D) (E)

(C)(B)

(D)

(E)

Different fuel moisture conditions

Complex wind speed and wind direction scenarios

Ara

gó

n

Results for the risk causative factorsResults

Wildfire hazard

Wildfire exposure

Burned area fire

transmission

Transmission

rate to houses

Lightning

ignitions

Anthropic

ignitions

Fire modelingHistorical data

(1) Fuel treatment prioritizationResults

Transmission vs. hazard on high

priority municipalities.

Preferences for fuel treatment programs locate on large fire source

municipality hazardous fuels. Protected area land designations

might locally represent a limiting factor for fuel treatments.

Avg.co

nd

itio

na

lfl

am

ele

ng

th(m

)Fire transmission (ha yr-1)

(2.1) Anthropic ignition prevention prioritizationResults

Anthropic ignitions vs. transmission

on high priority municipalities.

Preferences for accidental fire ignition prevention programs locate on

high transmission to houses and high anthropic ignition density

municipalities.

Tra

ns.

toh

ou

ses

(str

uct

ure

sy

r-1)

Anthropic ignitions (ignitions yr-1 × 103 ha)

(2.2) Lightning fire monitoring prioritizationResults

Lightning ignitions vs. transmission

on high priority municipalities.

Preferences for natural fire reintroduction locate on remote

municipalities with high lightning ignition densities and low

transmission (or fire scape risk) to residential houses.

Lightning ignitions (ignitions yr-1 × 103 ha)T

ran

s.to

ho

use

s(s

tru

ctu

res

yr-1

)

(3) Fire suppression opportunitiesResults

Hazard vs. transmission rate on high

priority municipalities.

Opportunities for a safe and efficient fire suppression locate on low

hazard and high transmission rate municipalities, where fire

containment can substantially reduce the number of burned houses.

Avg. conditional flame length (m)T

ran

s.ra

tes

(str

uct

ure

sh

a-1)

(4) Community action prioritizationResults

Houses on WUI vs. exposure on high

priority municipalities.

Priority areas for community action programs locate on municipalities

with several houses on the WUI and a high wildfire exposure.

Homeowners involvement on HIZ fuel maintenance is indispensable.

Exp

osu

re(a

nn

ual

HIB

P)

Residential houses (nº structures)

Concluding remarks

• In this study we present a wildfire risk management Cohesive

Strategy to minimize negative impacts from uncharacteristic

fires on the Mediterranean landscapes.

• More specifically, a set of maps was generated to prioritize

fuel treatment projects, implement ignition prevention

programs, assist lightning fire monitoring, identify

suppression opportunities and support community action.

• We used modeling quantitative outcomes for the key wildfire

risk causative factors to provide spatial priorities at

municipality level (n= 948) on a very large landscape (> 32

thousand km2).

Discussion and conclusions

Management implications

• Results revealed very heterogeneous spatial priorities across

the study area, and locally highlighted most appropriate

management strategies.

• Prioritizing management actions is necessary under

budgetary restrictions to efficiently allocate economic

resources.

• This study should be considered as a preliminary step to

downscaling efforts (e.g., landscape fuel treatment

optimization) on high priority Planning Areas.

• This methodological framework could be easily extended to

other Mediterranean fire-prone areas.

Discussion and conclusions

Many thanks for your attention!

ferminalcasena@eagrof.udl.cat