“Estimating the probability of fire in Amazonia”

Manoel Cardoso, Carlos Nobre, Gilvan Sampaio

University of New Hampshire

Institute for the Study of Earth, Oceans and Space

Centro de Previsão de Tempo e Estudos Climáticos INPE-CPTEC

Brazil

Source: Carvalho et al. 2001

Amazonia is changing

Future/past fires = ?

Processes related to fires (spatial and temporal scales)

Presence of fuel, flammability and ignition sources

in a simple view

Estimates of fires ? fire activity, area burned, biomass affected, …

Probability of fire (chance of fires to occur)

start by

N = Regions that are under conditions Cnf = Regions under conditions C, and that had fires

C

C

C Nnf

Pf

Estimating probability of fire (Pf)

Presence of fuel

Flammability

Ignition sources

Regions under conditions C

One way to estimate Pf:

Datasets used to estimate Pf

→ Factors identified in previous studies

Presence of fuel

Flammability

Ignition sources

Forest cover

Precipitation

Distance from roads

Data on fires AVHRR Fire pixels / Brazil 2000-02

INPE/CPTEC 0.01º, ~dy

Data on fuel MODIS forest cover / 2001

NASA 0.25º, ~yr

Data on flammabilityObserved precipitation / Jan-Apr

INPE/CPTEC 0.25º, dy

Data on flammabilityObserved precipitation / May-Sep

INPE/CPTEC 0.25º, dy

Data on flammabilityObserved precipitation / Oct-Dec

INPE/CPTEC 0.25º, dy

Data on ignition sources Distance from main roads

IBGE0.05º, ~5yr

Probability of fire, distance from roads and precipitation North Amazon / Jan-Apr

0

0.1

0.2

0.3

0.4

0.5

0.6

0 0.25 0.5 0.75 1 1.25 1.5 1.75 2 2.25 2.5 2.75 3

Dist. from roads (km)

Pro

b.

0-100100-200200-300300-400400-500500-600600-700700-800800-900900-1000

Results for North Amazon

Probability of fire, distance from roads and precipitation South Amazon / May-Sep

0

0.1

0.2

0.3

0.4

0.5

0.6

0 0.25 0.5 0.75 1 1.25 1.5 1.75 2 2.25 2.5 2.75 3

Dist. from roads (km)

Pro

b.

0-100100-200200-300300-400400-500500-600600-700700-800800-900900-1000

Results for South Amazon

Probability of fire, distance from roads and precipitation Northeast Amazon / Oct-Dec

0

0.1

0.2

0.3

0.4

0.5

0.6

0 0.25 0.5 0.75 1 1.25 1.5 1.75 2 2.25 2.5 2.75 3

Dist. from roads (km)

Pro

b.

0-100100-200200-300300-400400-500500-600600-700700-800800-900900-1000

Results for Northeast Amazon

General conclusions

Framework to produce interesting fire estimates: In units of probability/chance of fires to occur

Results are suitable for warning systems: operating at 0.25o and fire-season time scale

Results can be combined with fire behaviour data and be used to estimate fire consequences

Vegetation models Emissions models

In all regions, the probability of fire decreased with the distance from main roads and the amount of rainfall

The probability/chance of fire to occur was quantifyed based on distance from main roads, and rainfall during the dry season for three different regions in Amazonia