regional trends in land use/land cover change emissions of...
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Regionaltrendsinlanduse/landcoverchangeemissionsofCO2 inAsia
N.S.F.USAEast‐AsiaPacificSummerInstitute(EAPSI)
JapanSocietyofthePromotionofScience(JSPS)
Leonardo Calle, Benjamin Poulter,Prabir Patra
RECCAP/IPCC:Budget equations
The net land‐to‐atmosphere C flux (Fc) for carbon budget :
FC = FNPP + FRH + FLUC + FFire + Friver + FFF C flux changes in the biospheric (NPP‐net primary production, RH‐heterotrophicrespiration) , land‐use change (LUC), fire emissions, riverine export, fossil fuel (FF)
The South Asian Carbon Budget: Patra et al. 2013
Toatmosph
ere
To land
1PgC = 1015g 1TgC = 1012g
Synthesis of regional land fluxes from TDIs and DGVMs
Figure 6.15, IPCC‐AR5‐WG1, analysis by P. Patra
Top‐down(Inversion) fluxes include all CO2component
Bottom‐up (DGVMs ‐ dynamic global vegetation models) do not include LUC
H20 CO2
H20 CO2
Nutrients H20
Plant & Soil – Biophysics, Biogeochemistry ( carbon, water, and nutrient budgets )
Leaf‐levelphotosynthesis(Farquhar1980)Temp.feedbacks(todo:H2O)N‐limitations(rubisco)Canopylightmodeleddifferently
Leaf‐levelenergybudgetLatent&sensibleheatflux
DGVMs:LeaftoGlobe
TheAnthropocene
LandUseChangeandLM
Stockeretal.2014
Geographic areas for this study
Defined by the Asia Pacific Network (APN) for Global Change Research
(Project id:ARCP2013‐01CMY‐Patra/Canadell).
East Asia
South Asia
Southeast Asia
Carbon Emissions from Land Use and Land Cover Change (LULCC)
1980−1989 1990−1999 2000−2009
0.0
0.2
0.4
0.6
Land
Use
Flu
xP
gCy
r1
ModelsJULESLPJLPJGLPXVISIT
Southeast Asia
CarbonFlux: DGVMvariability
Calle et al., ERL, submited
Carbon in total biomass (above + below‐ground)
Estimated by the DGVMsThe Forest Resource Assessment report (FRA2010), Tier 1 methods
Carbon in aboveground biomass
Estimated by the DGVMs ; Baccini et al (2012) biomass datasetThe Forest Resource Assessment report (FRA2010), Tier 1 methods
Calle et al., ERL, submited
Carbon Emissions from Land Use and Land Cover Change (LULCC)
Calle et al., ERL, submitedIPCC
AR5
CO2Flux
Someone on Day 1mentioned Myanmar is 3rd on the list of forest loss (FRA2015)
JAMSTEC: BenchmarkDGVMC‐fluxes1. C‐fluxesfrom8‐DGVMs(TRENDY) asboundaryconditionsin
theCCSR/NIES/FRCGCatmosphericcirculationmodel(ACTM)2. Compareto:
• Up‐lookingTCCONobservationsofX‐CO2•Down‐lookingGOSAT(IBUKI)SatelliteobservationsofX‐CO2
3. EvaluatedSeasonalAmplitudeandInter‐hemisphericfluxrate4. EvaluateconfidenceindetectingLand‐UseChangesignalfrom
models
Conclusions
• Land‐use and land cover change (LULCC) now modelled by theDGVMs
• We estimated the LULCC emissions from 3 populous Asia regions
• LULCC in Southeast Asia is among the highest in the world (20%)
• This reduces the gap in our understanding of the regional carbonbudget, reported in IPCC AR5
• We are now trying to find ways to evaluate the DGVM fluxes for LULCC, separately from NEE
Thank you
DGVMCarbonFluxesCarbon fluxes due to LUC are calculated as the difference between a simulation with and without LUC
o This method of calculation helps isolate carbon fluxes from LUC, while accounting for effects due to a changing climate and increases in CO2
Legacy fluxes are delayed carbon fluxes that occur after LUCo These include carbon fluxes from soil respiration and decomposition of
downed wood, for example, after deforestation and before the forest regrows to previous levels
o Legacy fluxes are implicitly included in the DGVM LUC flux estimates, but currently, none of the DGVMs quantify the magnitude of legacy versus immediate fluxes
Biomass Turnovero Carbon in Soil and Litter decomposes to CO2 at daily or annual rates which
vary with temperature and soil‐moistureo A few models include coupled Carbon‐Nitrogen cycles that modify the
decomposition rates
DGVMCarbonFluxesfromLULCCDeforestation
o Generally, the majority of the carbon in vegetation (wood, leaves, roots) gets converted to CO2 in one year, but a fraction goes to Litter pool for delayed decomposition
Wood Harvesto 40% of harvested woody carbon (incld. all of leaves and roots) goes to
Litter for decompositiono 60% of woody carbon is split into ‘product pools’, decomposing at annual
rates of 1, 10, and 100 yrs• Product pools reflect wood products of fuel wood, paper products,
wood for furniture or homes (i.e., short‐term and long‐term storage)
Crop and Pasture (Managed Lands)o Many models treat crop and pasture as annual grasslands, with annual
harvest of the vegetation.o Only a few models simulate fertilization and irrigation, fewer models
include crop plant functional types
Howdoplantsrespondtochange?Rate of C
arbo
n Assim
ilatio
nDisturbance : Competition : Climate
Lambers etal.2008.PlantPhys.Ecology.
CarbonFlux: LandUseChangeAll RegionsEast AsiaSouth AsiaSoutheast Asia 44% of Global Emissions
0
10
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50
1901 1911 1921 1931 1941 1951 1961 1971 1981 1991 2001 2011
LU
LCC
flux
: Reg
iona
l / G
loba
l (%
)
Calle et al., ERL, submited