School of Engineering and TechnologyAsian Institute of Technology, Thailand

MODELING CARBON SINKS IN DIGITAL SPACES IN NAKHON NAYOK PROVINCE, THAILAND

Examination Committee: Dr. Nitin Kumar Tripathi (Chairperson)

Dr. Roland Cochard

Dr. I. V. Murali Krishna

Dr. Taravudh Tipdecho

BY

MD. AHASANUL HOQUE

RS&GISMay 2011

Introduction

CO2 is 390 ppm (NASA, 2010).

Increasing by 1.9 ppm/yr (BBC, 2010).

Surface temperature raised by 0.74 ± 0.18 °C (IPCC, 2007)

CO2 is a prominent greenhouse gas but fundamental for photosynthesis

Statement of the Problem Kyoto protocol : reduce GHGs emission

to 5.2% below 1990 levels by 2012. => only 1 year left

About 20 countries – 80% CO2 world’s emissions.

32 countries and 10 US states - started emission trading scheme.

Countries need to know terrestrial sequestration capacity but conventional method is destructive.

Remote sensing approach - for larger area in quick turn around time and cost effective.

Objective of the Study

Developing a grid based model for CO2 absorption by different land cover classes.

MethodologyMultispectral Satellite ImagesMultispectral Satellite Images

ASTER 15mBand 321

ASTER 15mBand 321

LANDSAT 30mBand 432

LANDSAT 30mBand 432

MODIS 250m Ref. Image (124)

MODIS 250m Ref. Image (124)

DN to Reflectance ConversionDN to Reflectance Conversion

Layer StackingLayer Stacking

Subset Image by AOISubset Image by AOI

Atmospheric Correction using FLAASH Model

Atmospheric Correction using FLAASH Model

Image EnhancementContrast Stretching

-Histogram Modification

Image EnhancementContrast Stretching

-Histogram Modification

Re-projection by MRT

Re-projection by MRT

Supervised ClassificationNearest Neighborhood

Supervised ClassificationNearest Neighborhood

Accuracy AssessmentAccuracy Assessment

Ground Truth dataGround

Truth data

Land Cover ClassesLand Cover Classes

OverlayOverlay

Field Vegetation Inventory

Field Vegetation Inventory

Biomass measurement

CarbonFix Standard 3.1

Biomass measurement

CarbonFix Standard 3.1

ValidationValidation

Volume Calculation by Allometric Eqn.

Volume Calculation by Allometric Eqn.

Generate NDVI Generate NDVI

Computation of NPP using CASA

& SEABAL model

Computation of NPP using CASA

& SEABAL model

Generate NPP/ CO2 Image

Generate NPP/ CO2 Image

Masking by Land Covers

Masking by Land Covers

Above Ground Carbon stock image

by land covers

Above Ground Carbon stock image

by land covers

Output CO2

Map

Output CO2

Map

NPP = APAR . LUE = NDVI. PAR . LUE

LUE = ε0 * T1 * T2 * Λ (Field et al., 1995)

Λ = the evaporative fraction from SEBAL. (Bastiaanssen and Ali, 2001) = 0.5+ (EET/PET) (Field et al., 1995)

Where ,ε° = globally uniform maximum (2.5g/MJ) andT1 & T2 relate to plant growth regulation (acclimation) by temperature

Where,NPP=net primary productionAPAR=Absorbed Photo-synthetically Active RadiationLUE=Light Use Efficiency factorPAR= Photo-synthetically Active Radiation

T2 = 1.185*{1+exp (0.2Topt-10-Tmon)}-1 * {1+exp(-0.3Topt-10+Tmon)}-1

T1 = 0.8 + 0.02 * Topt – 0.0005 * (Topt)2

APAR/PAR~NDVI (Daughtry et al., 1992)

CASA (Carnegie-Ames-Stanford Approach) model, to calculate NPP

Mathematical Representation of Model Algorithms

NDVI = ƒ( NIR, RED)

PAR = ƒ (K↓) (W/m2) = 0.51 for Tropical countries (Christensen and Goudriaan, 1993)

 T2 = 1.185 *{1+exp (0.2 * 28 -10 – 25 )}-1 * {1+exp(-0.3* 28 -10 + 25)}-1 = 0.0016098T1 = 0.8 + (0.02*28) - 0.0005 * (28) 2 = 0.968Where PET = is potential evapotranspiration = 119.5 mm/month for Thailand (Vudhivanikh V., 1996) and 124.62 mm in December for Nakhon Nayok (Cropwat-FAO, 2006) EET = is the estimated evapotranspiration= 1.6 mm/day for Evergreen Forest in Thailand (Tanaka, N., et al, 2008) and 110.52 mm in December (RID, 2006)

LUE = 3.49 for Forest & 3.45 for Open Scrubs

Study area

Geographical coordinates

14° 12' 11" North

101° 12' 53" East . Area of 2,122 km2

60%23%

17%

Agricul-tureForest

Data Used

ASTER 15mNo. of Cells: 8774320 Area : 197422.2 ha

LANDSAT 30mNo. of Cells: 2332260 Area : 209903.4 ha

MODIS 250mNo. of Cells: 32684 Area : 204275 ha

Field Data Collection

Number of Sample Points : 31

5m

5m Tree Layer

5m

5m Tree Layer

Shrubs Layer1m

1m

Shrubs Layer1m

1m HerblayerHerblayer 15m

15m

Tree Volume Measurement

Angle Measure (%)

Ground Distance

Collector’s height1.8 m

DBH Measurement

VT = (DBH/200)2 x 3.142 x Ht / 3 (FarmForest Line, 2010)Ht = [Angle(%) x Ground Distance/100] + Collector’s Height (1.8 m)

CO2 sink measurement: Field Method

CFS was created by 60 country organizations in 1999 & released at the Climate Conference in Bali in December 2007.

According to CarbonFix Standard 3.1 (CFS), 2010

Above Ground Woody Biomass= Tree Volume x Biomass expansion Factor x Wood Density x Carbon Fraction x C to CO2 factor

Above Ground non woody biomass= Fresh biomass x Dry to wet ratio x Carbon Fraction x C to CO2 factor

Normalized Difference Vegetation Index (NDVI)

Results & Discussion

ASTER 15mNo. of pixel : 8774320

LANDSAT 30mNo. of pixel : 2332260

MODIS 250mNo. of pixel : 32684

Landcover classification images

ASTER 15mAccuracy: 89.36 %

LANDSAT 30mAccuracy: 82.98 %

MODIS 250mAccuracy: 72.34 %

Model Results of NPP

ASTER 15mSinked CO2 = 6.12 ml. ton

LANDSAT 30 mSinked CO2 = 8.83 mil. ton

MODIS 250mSinked CO2 = 10.39 mil. ton

CO2 sink = 3.25 mil. ton CO2 sink = 1.85 mil.tonCO2 sink = 3.23 mil.tonLANDSAT Primary Forest

LANDSAT Sparse Forest LANDSAT Open Scrubs

CO2 sinking by landcovers

Validation of the Model Results

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 170

0.5

1

1.5

2

Forest CO2 sink from field measurement

Sample Points

sin

ked C

O2 (

ton)

1 2 3 4 5 6 7 8 9 10 11 12 13 140

0.10.20.30.40.50.60.70.8

Open. Scrubs CO2 sink from field measurement

Sample Points

sin

ked C

O2 (

ton)

big trees

new trees

large healthy vegetation

Crop residuals

0.8 0.85 0.9 0.95 1 1.05 1.10

0.5

1

1.5

2

f(x) = − 5.0738705202 x + 5.56769036363R² = 0.754202987384012

ASTER 15m vs Forest Field Measured CO2

ASTER 15m CO2

Fie

ld C

O2

0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.40

0.5

1

1.5

2

f(x) = − 2.204561213891 x + 3.093836070613R² = 0.697496375316507

LANDSAT 30m vs Forest Field Measured CO2

LANDSAT 30m CO2Fie

ld C

O2

1 1.1 1.2 1.3 1.4 1.5 1.60

0.5

1

1.5

2

f(x) = − 0.500632270471 x + 1.37102275924R² = 0.0290934148232874

MODIS 250m vs Forest Field mesured CO2

MODIS 250m CO2

Fie

ld C

O2

R² = 0.754 R² = 0.697 R² = 0.029

Validation of the Model Results

Validation of the Model Results

0.5 0.6 0.7 0.8 0.9 10

0.050.1

0.150.2

0.250.3

0.350.4

f(x) = − 0.86232188072 x + 0.90576869276R² = 0.615759641562017

ASTER 15m vs Open Scrubs Field measured CO2

ASTER 15m CO2

Fie

ld C

O2

0.5 0.6 0.7 0.8 0.9 1 1.1 1.20

0.2

0.4

0.6

0.8

f(x) = 0.965643316214 x − 0.5092912937307R² = 0.567542565043668

LANDSAT 30m vs open Scrubs field measured CO2

LANDSAT 30m CO2F

ield

CO

20.50.60.70.80.9 1 1.11.21.31.41.5

0

0.2

0.4

0.6

0.8

f(x) = 0.3085631929346 x + 0.0006183342084R² = 0.0579838674937422

MODIS 250m vs Open Scrubs field mesured CO2

MODIS 250m CO2

Fie

ld C

O2

R² = 0.615 R² = 0. 657 R² = 0.058

Normalizing LANDSAT & MODIS to ASTER

ASTER 15m LANDSAT 30m

MODIS 250m0.00

2.00

4.00

6.00

8.00

10.00

12.00

6.12

8.33

10.39

sinked CO2

Images

sin

ekd C

o2 (

million t

on)

Converting value to Same Unit area 15m x 15m multiplied

By 4 to Landsat & 277 to Modis

ASTER 15m LANDSAT 30m

MODIS 250m

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.006.12

2.08

0.04

sinked CO2

Images

sin

ked C

O2 (

million t

on)

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.80

0.10.20.30.40.50.60.70.80.9

f(x) = 0.804694551529963 x + 0.247417541477452R² = 0.739154576842278

NDVILinear (NDVI)

MODIS 250m NDVI

LA

ND

SA

T 3

0m

ND

VI

LANDSAT 30m MODIS 250m0

2

4

6

8

10

12

8.33 8.33

2.06

ScaledActual

Images

sin

ked C

O2 (

million t

on)

LANDSAT 30m & MODIS 250m Image acquisition date is same LANDSAT 30m NDVI & MODIS 250m NDVI 41 points correlation is 0.739

Therefore , assuming LANDSAT 30m result is actual CO2 sink value

Actual CO2 sink = 0.801 x MODIS 250m sink (ton)

Downscaling MODIS 250m to MODIS 30m

MODIS 30m NDVI MODIS 30m Land Cover Classes No. of pixel = 2332116Sinked CO2 =2.66 mil. ton

Downscaling MODIS 250m to MODIS 15m

No. of Cells = 9515056Sinked CO2 = 10.85 mil. ton

MODIS 15m NDVI MODIS 15m Land Cover Classes

Comparison among downscaled image and other images sink

0.00

2.00

4.00

6.00

8.00

10.00

12.00

6.12

2.08

0.04

2.66

10.85sinked ...

images

sink

ed C

O2

in m

illio

n to

n

ASTER 1

5m

LANDSAT.

..

MODIS

...

ds_M

ODI..

.

ds_M

ODI..

.0

2

4

6

8

10

12

6.12

8.33

10.39 10.62 10.85sinked ...

Images

sin

ked C

O2 in m

illion t

on

Pixel based Value of each images sink

Normalized sink value of each image

MODIS 250m to LANDSAT 30m sink

ASTER

15m

MOD

IS 1

5m

LAND

SAT

30m

MOD

IS 3

0m0

2

4

6

8

1012

6.12 6.128.33 8.33

4.732.29

scaledactual

Images

Sin

ked

Co2

( m

illio

n t

on)

ASTER 15m, LANDSAT 30m & downscaled MODIS sink comparison

LANDSAT 30m sink = 0.79 x downscaled MODIS 30m sink

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.80

0.10.20.30.40.50.60.70.80.9

f(x) = 0.862208280173626 x + 0.201038337478708R² = 0.718970962613201

NDVILinear (NDVI)

MODIS 30m NDVI

LA

ND

SA

T 3

0m

ND

VI

NDVI correlation between LANDSAT 30m and MODIS 30m

R² = 0.719

Conclusion CASA algorithms can give the precise and accurate result if SEBAL data are of

same time The finer the satellite resolution the more accurate CO2 result.

Medium resolution LANDSAT provided net CO2 sink stock estimate as 8.33 million tonnes of CO2 in Nakhon Nayok.

Scale factor 0.801 for MODIS 250m for achieving the amount of LANDSAT 30m sequestered CO2.

A general average stock can be assumed to meet Kyoto Protocol or CDM target of carbon quantities.

MODIS data can be used to find terrestrial sink accurately.

Recommendations

Proposed methodology with MODIS can be used for regional, or global scale carbon sequestration measuring and monitoring tool.

Research to measure the CO2 emission data of the study area & required afforestation for remaining CO2.

MODIS 250m CO2 Map

With deep gratitude to Govt. of Japan for supporting to study in AIT.

Thanks to all

Let us use

MODIS free data

to find more CO2 sinks & make a

healthier and

green environm

ent.