• Tiada Hasil Ditemukan

Cal/Val of MODIS Fire Hot Spots Using High Resolution Imagery Cal/Val of MODIS Fire Hot Spots

N/A
N/A
Protected

Academic year: 2022

Share "Cal/Val of MODIS Fire Hot Spots Using High Resolution Imagery Cal/Val of MODIS Fire Hot Spots"

Copied!
28
0
0

Tekspenuh

(1)

Cal/Val of MODIS Fire Hot Spots Using High Resolution Imagery Cal/Val of MODIS Fire Hot Spots

Using High Resolution Imagery

S. C. Liew, K. H. Lim, C. M. Shen, A. Lim and L. K. Kwoh

CRISP, National University of Singapore email: crslsc@nus.edu.sg

S. C. Liew, K. H. Lim, C. M. Shen, A. Lim and L. K. Kwoh

CRISP, National University of Singapore email: crslsc@nus.edu.sg

SEA-GOFC Fire Workshop

22 - 25 January 2002, Phuket, Thailand

(2)

Introduction Introduction

MODIS : Key instrument on-board Terra (EOS AM-1) satellite, launched in December 18, 1999

It has 36 spectral bands, ranging from 0.4 to 14 µµµµm

Resolution from 250m (2 bands), 500m (5 bands), 1km (29 bands)

One of the unique feature is its direct broadcast capability

It transmits science data via X-band to ground

Any ground station equipped with a 3m or larger reception system may receive the direct broadcast data

It is particularly useful for regional ground station to perform near-real-time environmental monitoring

MODIS : Key instrument on-board Terra (EOS AM-1) satellite, launched in December 18, 1999

It has 36 spectral bands, ranging from 0.4 to 14 µµµµm

Resolution from 250m (2 bands), 500m (5 bands), 1km (29 bands)

One of the unique feature is its direct broadcast capability

It transmits science data via X-band to ground

Any ground station equipped with a 3m or larger reception system may receive the direct broadcast data

It is particularly useful for regional ground station to perform near-real-time environmental monitoring

(3)

Reception and Applications of MODIS Data in Forest Fire Monitoring

Reception and Applications of MODIS Data in Forest Fire Monitoring

CRISP has been preparing to receive MODIS data since it was launched in late 1999.

October 2000 : 6-m antenna installed

Processing up to level 1-B successfully implemented

On 3 March 2001, the first MODIS data was received and processed

successfully

Potential applications:

Fire detection

fire temperature and fire area retrieval burn scar mapping

aerosol retrieval

CRISP has been preparing to receive MODIS data since it was launched in late 1999.

October 2000 : 6-m antenna installed

Processing up to level 1-B successfully implemented

On 3 March 2001, the first MODIS data was received and processed

successfully

Potential applications:

Fire detection

fire temperature and fire area retrieval burn scar mapping

aerosol retrieval

(4)

Daily Fire Monitoring Operation at CRISP

Daily Fire Monitoring Operation at CRISP

Commissioned by the Ministry of Environment, Singapore

ASEAN Regional Haze Action Plan

Sets out co-operative measures amongst ASEAN member countries to address the problem of smoke haze in the region

arising from land and forest fires

Singapore takes up the responsibility of coordinating the regional land and forest fire monitoring mechanisms.

Commissioned by the Ministry of Environment, Singapore

ASEAN Regional Haze Action Plan

Sets out co-operative measures amongst ASEAN member countries to address the problem of smoke haze in the region

arising from land and forest fires

Singapore takes up the responsibility of coordinating the regional land and forest fire monitoring mechanisms.

(5)

Daily Fire Monitoring Operation at CRISP

Daily Fire Monitoring Operation at CRISP

Near real-time operation

Determination of fire locations

Determination of types of land cover burnt (eg. Plantations, peat swamp, natural forests, etc.)

Production of burn scar maps

Near real-time operation

Determination of fire locations

Determination of types of land cover burnt (eg. Plantations, peat swamp, natural forests, etc.)

Production of burn scar maps

(6)

Daily Fire Monitoring Operation Daily Fire Monitoring Operation

NOAA 14,16 AVHRR

Global Coverage at 1km resolution Derive ‘Hotspots’

SPOT 1, 2 & 4

20m ground resolution

Provide ‘zoom-in’ views of fire activities Satellite image acquisition guided by

‘Hotspots’ derived from NOAA AVHRR data

NOAA 14,16 AVHRR

Global Coverage at 1km resolution Derive ‘Hotspots’

SPOT 1, 2 & 4

20m ground resolution

Provide ‘zoom-in’ views of fire activities Satellite image acquisition guided by

‘Hotspots’ derived from NOAA AVHRR data

(7)

Hotspots derived from NOAA AVHRR Data

Hot Spots

Planning SPOT Passes Using NOAA AVHRR Hotspots

Planning SPOT Passes Using NOAA AVHRR Hotspots

(8)

NOAA14 2000 Jul 14 08:59 UTC Hot Spots

Smoke Haze

(9)

Programming SPOT Satellites Programming SPOT Satellites

(10)

Standard Product

Annotated Fire Scene processed to Level 2A

(11)

Fire Report Fire Report

(12)

Modis VIS/NIR/SWIR Bands (Land/Aerosol)

Modis VIS/NIR/SWIR Bands (Land/Aerosol)

1 (Red) : 620 - 670 nm (250 m)

2 (NIR) : 841 - 876 nm (250 m)

3 (Blue) : 459 - 479 nm (500 m)

4 (Green) : 545 - 565 nm (500 m)

5 (SWIR) : 1230 - 1250 nm (500 m)

6 (SWIR) : 1628 - 1652 nm (500 m)

7 (SWIR) : 2105 - 2155 nm (500 m)

1 (Red) : 620 - 670 nm (250 m)

2 (NIR) : 841 - 876 nm (250 m)

3 (Blue) : 459 - 479 nm (500 m)

4 (Green) : 545 - 565 nm (500 m)

5 (SWIR) : 1230 - 1250 nm (500 m)

6 (SWIR) : 1628 - 1652 nm (500 m)

7 (SWIR) : 2105 - 2155 nm (500 m)

(13)

Modis MWIR/Thermal IR Bands (Surface/Cloud Temperature) Modis MWIR/Thermal IR Bands

(Surface/Cloud Temperature)

Band 20 : 3.660 - 3.840 µµµµm

Band 21 : 3.929 - 3.989 µµµµm (low gain)

Band 22 : 3.929 - 3.989 µµµµm (high gain)

Band 23 : 4.020 - 4.080 µµµµm

Band 31 : 10.780 - 11.280 µµµµm

Band 32 : 11.770 - 12.270 µµµµm

Band 20 : 3.660 - 3.840 µµµµm

Band 21 : 3.929 - 3.989 µµµµm (low gain)

Band 22 : 3.929 - 3.989 µµµµm (high gain)

Band 23 : 4.020 - 4.080 µµµµm

Band 31 : 10.780 - 11.280 µµµµm

Band 32 : 11.770 - 12.270 µµµµm

(14)

Advantages of MODIS Advantages of MODIS

High positional accuracy

High radiometric precision (12 bits encoding)

Moderate spatial resolution modes available (250 m, 500 m)

High saturation level

350 K (band 22) 500 K (band 21) 400 K (band 31)

High positional accuracy

High radiometric precision (12 bits encoding)

Moderate spatial resolution modes available (250 m, 500 m)

High saturation level

350 K (band 22) 500 K (band 21) 400 K (band 31)

(15)

MODIS Hot Spots MODIS Hot Spots

T21 > 360 K

Or (T31 > 320 K and T21 - T31 > 20 K)

Flag hot spots in sun glint areas

Exclude cloud areas

T21 > 360 K

Or (T31 > 320 K and T21 - T31 > 20 K)

Flag hot spots in sun glint areas

Exclude cloud areas

(16)

Case Study : 23 May 2001 Fire in Sarawak, Malaysia Case Study : 23 May 2001 Fire in Sarawak, Malaysia

(17)

MODIS - 23 May 2001 MODIS - 23 May 2001

(18)

SPOT Fire Locations A 2.8328N 111.9922E B 2.8344N 111.9994E C 2.8308N 111.9997E MODIS Hot Spots

2.8387N 111.9912E 2.8373N 112.0008E 2.8295N 111.9899E 2.8281N 111.9995E

MODIS Hot Spots validated with SPOT fires 2001-05-23

MODIS Hot Spots validated with SPOT fires 2001-05-23

(19)

MODIS Hot Spots validated with SPOT fires 2001-05-23

MODIS Hot Spots validated with SPOT fires 2001-05-23

SPOT Fires

D 2.5633N 111.9192E E 2.5528N 111.9158E F 2.5533N 111.9211E G 2.5550N 111.9258E H 2.5531N 111.9303E

MODIS Hot Spots

2.5642N 111.9143E 2.5628N 111.9239E 2.5563N 111.9034E 2.5549N 111.9130E 2.5535N 111.9226E 2.5521N 111.9322E 2.5508N 111.9417E 2.5456N 111.9117E 2.5443N 111.9213E

(20)

SWIR Band of SPOT4 Helps to Locate Fires Without Visible

Smoke Plumes

SWIR Band of SPOT4 Helps to Locate Fires Without Visible

Smoke Plumes

R,G,B = Bands 4,3,2 R,G,B = Bands 3,2,1

(21)

Hot Spots

Another Case: 2002 Jan 19

Fire in Riau Province, Sumatra, Indonesia Another Case: 2002 Jan 19

Fire in Riau Province, Sumatra, Indonesia

MODIS Image

(22)

SPOT - 2002 Jan 19 SPOT - 2002 Jan 19

(23)

Retrieval of Subpixel Fire Temperature and Fire Area

Retrieval of Subpixel Fire Temperature and Fire Area

Fire pixel is assumed to radiate like a blackbody with a constant emissivity.

Assume only two temperature fields

Fire pixel is assumed to radiate like a blackbody with a constant emissivity.

Assume only two temperature fields

Fire Temperature Tf Fractional area = f

Background Temperature Tb

Fractional area = 1-f

(24)

Apparent Temperature of a Fire Pixel Apparent Temperature of a Fire Pixel

Fire Area (Fraction of pixel) = f

Fire Temperature = Tf Background Temperature = Tb

Radiance, L K f

c T

f

c T

f b

= − +

exp( 2 / ) 1 exp( 2 / )

1

λ λ 1

Apparent Temperature

( )

T c

= K L +

2 1

λ ln( / 1)

(25)

Two-Bands Algorithm Two-Bands Algorithm

T1 = apparent temperature detected in band-1

T2 = apparent temperature detected in band-2

Given T1 and T2 of a hot-spot pixel, invert the temperature equations to obtain the fractional fire area f and subpixel fire temperature Tf. (Two unknowns, two equations).

Analytic Solution is not possible.

Use numerical method of solution: Newton- Raphson

T1 = apparent temperature detected in band-1

T2 = apparent temperature detected in band-2

Given T1 and T2 of a hot-spot pixel, invert the temperature equations to obtain the fractional fire area f and subpixel fire temperature Tf. (Two unknowns, two equations).

Analytic Solution is not possible.

Use numerical method of solution: Newton- Raphson

(26)

Determination of background temperature Tb Determination of background temperature Tb

Background temperature is taken to be the mean of a Region Of Interest(ROI) that was visually selected from the image.

The ROI was taken from non-burning areas near the hotspot region.

Background temperature is taken to be the mean of a Region Of Interest(ROI) that was visually selected from the image.

The ROI was taken from non-burning areas near the hotspot region.

(27)

868.25 848.83 942.88 780.11 819.12 814.24 876.91 864.37 897.58 868.25 793.49 810.95 807.62 805.52 785.04 814.24 856.32

Tf

0.0041 308.41

338.86 123.960

-16.548

0.0034 307.91

336.82 123.966

-16.551

0.0026 307.80

346.66 123.843

-16.510

0.0037 307.74

329.66 123.822

-16.508

0.0058 309.01

333.70 126.330

-16.554

0.0093 310.11

333.19 126.336

-16.544

0.0093 310.37

339.77 126.807

-15.954

0.0052 308.96

338.45 126.812

-15.963

0.0115 310.88

341.94 125.847

-14.787

0.0111 310.70

338.86 125.854

-14.788

0.0070 309.36

331.03 126.052

-14.598

0.0131 310.80

332.85 126.023

-14.595

0.0065 309.24

332.50 126.059

-14.600

0.0102 310.27

332.28 126.030

-14.596

0.0061 308.95

330.16 127.035

-14.658

0.0119 310.64

333.19 127.042

-14.651

0.0037 311.04

351.73 114.565

-2.577

f T2

T1 longitude

latitude

(28)

Conclusions Conclusions

MODIS hot spots can be validated using SPOT images.

Most fires detected by SPOT are also detected by MODIS.

Some fires in SPOT are not detected by

MODIS - small fires? Hot spots criteria too stringent? Need Adaptive thresholds.

Some hot spots in MODIS are not detected in SPOT - No visible smoke plumes, but may be detected if SWIR band of SPOT 4 is used.

Retrieval of subpixel fire temperature and area has been attempted, seems promising.

MODIS hot spots can be validated using SPOT images.

Most fires detected by SPOT are also detected by MODIS.

Some fires in SPOT are not detected by

MODIS - small fires? Hot spots criteria too stringent? Need Adaptive thresholds.

Some hot spots in MODIS are not detected in SPOT - No visible smoke plumes, but may be detected if SWIR band of SPOT 4 is used.

Retrieval of subpixel fire temperature and area has been attempted, seems promising.

Rujukan

DOKUMEN BERKAITAN

If semi transverse ventilated model has a same outlet size as longitudinal ventilated model, the average temperature of the cable tunnel may be further reducing as it may exhaust

Figure 9 represents the correlation between temperature distribution and current distribution at the top of transformer tank with the presence of HST C using mineral oil

Whoever commits mischief by fire or any explosive substance, intending to cause, or knowing it to be likely that he will thereby cause, the destruction of any.. building which

Performance of the prototypes in terms of fire resistant/fire rating and sound absorption capability have been evaluated by experiment and estimation using standard

Figure 3.6: Spots with moderate fold change in control gels of Musca domestica 3 rd instar larvae thiol proteome... Figure 3.7: Spots with moderate fold change in treated gels

(1) To compare the results of fire damage analysis using NOAA AVHRR cumulative hot spots images and SPOT quicklook burn scar maps.. (2) To study the affected vegetation types

In addition, the finding from this study is the key problem towards the segmentation approaches to segment the iris pigment spots, in which no available method

The slab type specimens were used for evaluating fire resistance using ASTM E119, Standard Test Methods for Fire Tests of Building Construction and Materials, and the cube