Gridded Biome-BGC Simulation with Explicit

Fire-disturbance

Sinkyu Kang, John Kimball, Steve W. RunningNumerical Terradynamic Simulation Group,

School of Forestry, Univeristy of Montan

Purpose

• Demonstrate Gridded Biome-BGC run in BOREAS.

• Illustrate Biome-BGC modification for explicit fire-disturbance simulation

Process of Gridded BGC

• Batch run of Biome-BGC combined with input and output modules

• Using IDL platform

Spatial & temporal data

INI, EPC, MET file for point Biome BGC run

Batch run of point Biome BGC

Generate gridded outputs

Considering Explicit Fire-Disturbance

Raw Data Size and location

Year Month Day LON(dd) LAT(dd) Start_Date Size (ha)1959 5 24 -105.586 54.318 5/24/1960 242.911959 6 8 -104.206 53.602 6/8/1959 323.881959 5 24 -101.002 52.605 5/24/1959 216.5991959 5 21 -100.846 52.387 5/21/1959 251.0121959 5 23 -100.87 52.569 5/23/1959 291.4981959 5 22 -100.978 52.598 5/22/1959 595.1421959 7 15 -100.233 56.483 7/15/1959 663.1581960 8 24 -105.95 55.55 8/24/1960 9311.741960 7 22 -105.8 55.67 7/22/1960 728.741960 8 14 -105.77 56.52 8/14/1960 21246.961960 8 10 -105.45 55.52 8/10/1960 2429.1491960 7 26 -104.558 54.699 7/26/1960 16963.561960 8 18 -103.63 56.3 8/18/1960 404.851960 8 9 -103.57 56.35 8/9/1960 364.37

Radius (km) Rows Cols1 32 81 40 161 52 351 55 361 53 361 52 361 6 405 17 62 15 78 5 73 17 97 27 141 8 201 7 20

Before 1959: constant fire mortality

After 1959: external fire mortality from the raw data

Generate fire grid0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 1 0 0 0 0 0 0 0 0

0 0 1 1 1 0 0 0 0 0

0 0 1 1 1 0 0 0 0 0

0 0 1 1 1 0 0 0 0 0

0 0 1 1 1 0 0 0 0 0

0 0 1 1 1 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 1 0 0 0 0 0 0 0 0

0 0 1 1 1 0 0 0 0 0

0 0 1 1 1 0 0 0 0 0

0 0 1 1 1 0 0 0 0 0

0 0 1 1 1 0 0 0 0 0

0 0 1 1 1 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 1 0 0 0 0 0 0 0 0

0 0 1 1 1 0 0 0 0 0

0 0 1 1 1 0 0 0 0 0

0 0 1 1 1 0 0 0 0 0

0 0 1 1 1 0 0 0 0 0

0 0 1 1 1 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 1 0 0 0 0 0 0 0 0

0 0 1 1 1 0 0 0 0 0

0 0 1 1 1 0 0 0 0 0

0 0 1 1 1 0 0 0 0 0

0 0 1 1 1 0 0 0 0 0

0 0 1 1 1 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 1 0 0 0 0 0 0 0 0

0 0 1 1 1 0 0 0 0 0

0 0 1 1 1 0 0 0 0 0

0 0 1 1 1 0 0 0 0 0

0 0 1 1 1 0 0 0 0 0

0 0 1 1 1 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0

Year

1971 01972 01973 01974 01975 01976 01977 01978 01979 01980 11981 01982 01983 01984 01985 01986 01987 01988 01989 11990 0

cell[i,j] annual fire file

Considering Explicit Fire-Disturbance

87

83

84

85

86

Considering Explicit Fire-Disturbance

1.0 (DIM) multiplier for shortwave radiation CO2_CONTROL (keyword - do not remove) 1 (flag) 0=constant 1=vary with file 2=constant, file for Ndep286.923 (ppm) constant atmospheric CO2 concentration kco21862.txt (file) annual variable CO2 filename FIRE_CONTROL (keyword - do not remove) 1 (flag) 0=constant fire mortality 1=vary with file fire-5-14.txt (file) annual variable fire mortality (year fire_mortality) SITE (keyword) start of site physical constants block

Modifed INI & EPC files

Run Modified Biome-BGC

ECOPHYS ENF-cool (wet conifer) 1 (flag) 1 = WOODY 0 = NON-WOODY …………………………………………………….0.005 (1/yr) annual whole-plant mortality fraction 0.005 (1/yr) mean annual fire mortality fraction 0.26 (1/yr) annual carbon fraction consumed by fire 1.5 (ratio) (ALLOCATION) new fine root C : new leaf C1.1 (ratio) (ALLOCATION) new stem C : new leaf C

0

50

100

150

200

250

1900 1920 1940 1960 1980 2000

Year

ET (

mm

/y)

& N

PP

(g

C/m

2/y

)

0

2

4

6

8

10

LA

I (m

2/m

2)

ET NPP LAI

ET

(m

m/y

) &

NP

P (

gC/m

2/y)

LA

I (m

2/m

2)

Dai

ly f

ire

mor

talit

y

Constant fire mortality > 1959 < Explicit fire occurrence

Internal fire-disturbance External fire-disturbance

Modification of Biome-BGC

Biome-BGC v.411 47 source files 8 header files 2 library files

In this study, even this small change demanded

modification of 7 source files modification of 4 header files addition of a new subroutine source file

Application to the Boreal Forest Biome

Grid size (simulation unit): 66 columns and 60 rows (ca. 660300km2)

Each simulation uses identical land cover and soil property over the entire grid identical spatial meteorological variable (1994~1996)

Every simulation differs in land cover types (DBF, Grass, DC, WC) constant or varying ambient CO2 and internal or external fire-

disturbance Nine climate change scenario (control, 2oC, 20%

precipitation)

Total 108 cases of gridded Biome-BGC runs

Experimental Design

660km

300km

Land Cover

Topography

N

N

Climate (3-yr mean)

Tmax Tmin

Precipitation Radiation

Sample Result 1 – Land cover

DBF(412, 87.5 g/m2)

Grass(347, 48.6 g/m2)

WC(140, 8.7 g/m2)

DC(279, 26.2 g/m2)

Sample Result 2 – CO2

Difference (23, 2.8 g/m2)

Const. CO2 – Increasing CO2

WC, Const. CO2(140, 8.7 g/m2)

WC, Increasing CO2(163, 11.1 g/m2)

Sample Result 3 - FireDifference (-1.4, 3.7 g/m2)

External fire – Increasing CO2

WC, External fire(161, 11.8 g/m2)

WC, Increasing CO2(163, 11.1 g/m2)

130

150

170

Constant Increasing Fire

NPP (

gC

/m2)

Sample Result 4 – Climate Change

PRCP*TEMP: PRCP(-1,0,+1), TEMP(-1,0,+1), EX: +1-1 (1.2*prcp & -2 of Temp.)

00

+10 -10

+1+1 +1-1 -1+1 -1-1

DBF, Const. CO2

Climate Scenario

0.8P

1.2P(+2T)

1.2P

0.8P(-2T)

0.8P(+2T)

1.2P(-2T)

300 350 400 450 500

C

1.2P

0.8P

1.2P(+2T)

1.2P(- 2T)

0.8P(+2T)

0.8P(- 2T)

NPP (gC/m2)

Future consideration

Model InitializationSpin-up run: – initialize soil and vegetation variable at balanced

equilibrium condition– time consuming process as number of gridcells increase

Extrapolation from satellite measurement: – satellite-driven LAI initialize vegetation carbon variables

using allometry rules (Landsat & MODIS in watershed and regional scale)

Replace model phenology with RS phenology (ex. MODIS)

MOD17: daily PSN (MOD17A2)

BGC: daily PSN with spin-up simulation

MOD15-BGC: daily PSN using input LAI from MOD15

0

2

4

6

0 60 120 180 240 300 360

MOD17

BGC

MOD15- BGCP

SN

(gC

m-2 d

-1)

yearday

Grass

Reinitialize usingsatellite-driven LAI + allometry from spin-up simulation

0

1

2

3

4

5

6

7

8

0 60 120 180 240 300 360

Yearday

LA

I (m

2/m

2)

MODIS

BGC

COOP. Weather Station, Alabama

0

2

4

6

8

0 60 120 180 240 300 360

yearday

Pro

jecte

d L

AI

(m2/m

2)

Ulsan Daekwalryung

Warm (13.3 oC)

Cool (6.2 oC)

90

100

110

120

130

140

90 100 110 120 130 140

Predicted (Model- S, yearday)

Ob

serv

ed

(yeard

ay)

MAE = 1.7Bias = 1.7

90

100

110

120

130

140

90 100 110 120 130 140

Predicted (Model- 8, yearday)

Ob

serv

ed

(yeard

ay)

MAE = 4.9Bias = -4.9

90

100

110

120

130

140

1995 1996 1997 1998 1999 2000 2001 2002year

yeard

ay

Model-SModel-8

KBmean

TSTTsum )1(

1

)()2(j

otavgsum CTTT

)()3( 30TfTST

Meteorological Data

Soil Data

1.Respiration 2.Temperature 3.Water content 4.SOM

Field LAI

DEM

Spatially-explicit estimations

RS

NDVI

Field sampling & measurement

LAI-NDVI model

Meteorological Models 1.Air temperature 2.Precipitation 3.Solar radiation 4.Vapor pressure deficit

Soil respiration

model

Soil moisture

model

Soil temperature

model

Model Overview

0

1

2

3

4

5

6

0 61 122 183 244 305 366

LA

I

Leaf emergency (Je) (Ta-5oC) > 88oC

End of litterfall (Jb) (Ta-10oC) < -150oC

Maximum LAI (Jm)(Aug. 15 in this study)

LAI model

max1))(exp(

1))(exp(LAI

JJ

JJLAI

m

e

LAI-NDVI model

LAI model

NDVI (Landsat TM,

August, 1991)

Mean 0.55

STDEV 0.13

(solid dots are locations where LAI was measured.)

LAI-NDVI model

Landsat TM image in Aug. 1991

LAI measured in Aug. 1998 and 1999 using LI-COR 2000

120 (0~3.8 m2 m-2) 125 130

135 140 145

LAI-NDVI Model : Leaf Emergence and Expand