CCSM Biogeochemistry WG Plans CCSM1-carbon (Fung, Doney, Lindsay, John) –Interactive land (CASA’) and ocean (OCMIP’) C cycles; prognostic CO 2 for atmospheric radiation –Planned submission to IPCC 4 th Assessment CCSM3-carbon: (2 versions) –Port CASA’/OCMIP’ to CCSM3 physics – (Fung, Doney, Lindsay, John, Murphy, SciDAC Collaboration) –Land: C-N coupling, disturbance (Thornton et al.) Ocn: marine ecosystem dynamics (Moore et al.) –Planned submission to IPCC 4 th Assessment CCSM3-carbon+ –Dust  marine productivity  C –Land atmosphere coupling and active chemistry

CCSM1-Carbon Inez Fung, Scott Doney, Jasmin John, Keith Lindsay Modules Spin-up Results from Control –Atm –Land –Ocean Fossil Fuel emission

Modeler’s View of the Global C Cycle Atmosphere CO 2 = 280 ppmv (560 PgC) + … Ocean Circ. + BGC Biophysics + BGC Pg C 2000 Pg C 90± 60± Turnover Time of C yr Turnover time of C 10 1 yr FF

COUPLING OF BIOGEOCHEMISTRY W BIOPHYSICS } NPP R_h L R WGPPR_a } GPP from LSM dL/dt =  _ L * NPP – L/(  _ bkgd +  _ cold-drought ) All fluxes and pools updated 20 minutes H2OH2O LAI Energy CO 2 CASA’

Physical framework -NCOM global model (CCSM- ocean 1.4, x3 grid) -equilibrium solutions (~5-10kyr) Ocean Carbon Model Intercomparison Project (OCMIP) -carbonate thermodynamics and air-sea fluxes -prognostic biotic model Enhancements -replace PO 4 restoring w/ prognostic export flux -incorporate Fe limitation and Fe cycling Iron-Carbon Biogeochemistry Model

CCSM1-Carbon Modules Spin-upSpin-up Results from Control –Atm –Land –Ocean Fossil Fuel emission

Spin-up Strategy Reminder: Carbon inventory adjusts to climate Spin-up Goal: find C distribution in eqm with the climate Challenge: fickle models and climate Three flavors of CO 2 : –Tracers CO 2 in atm = CO 2-tracer (x,y,z,t) (diagnostic of surface fluxes) 3+ inert tracers: net land+ocean; net land; net ocean –Biogeochemistry CO 2 = CO 2-tracer (x,y,sfc, t) To drive fluxes into ocean Sensed by terrestrial photosynthesis –Radiative CO 2 = CO 2-tracer (x,y,column, t)

Coupling and Spin-up Strategy ocean BGC spin-up active ocean O(10 3 )y land BGC spin-up active land/atm clim. or coupled model SSTs O(10 2 )y coupled physics land/ocn BGC adjustment C Tracer =prog C BGC =280 C Rad =280 C Tracer =prog C BGC =prog C Rad =280 C Tracer =prog C BGC =prog C Rad =prog coupled physics land/ocn/atm BGC adjustment coupled physics fully coupled carbon-climate c4.18 ~600 yr (03/25/04) start from y=50 of c ppm c yr c yr CCSM 1.4 physics (with some changes) at T31/x3

Coupled Carbon-Climate Model NCAR CCSM1 with interactive terrestrial and oceanic C cycles, Prognostic CO 2 (x,y,z,t) Control Run: ~600years –Quantify climate effects on the carbon cycle –No imposed trends (e.g. CO2 fertilization, N fertilization, land use modification...) –Determine natural variability –Background for CO2 sink detection FF Experiment – specify FF emission since 1820

CCSM1-Carbon Modules Spin-up Results from ControlResults from Control –Atm –Land –Ocean Fossil Fuel emission

Multi-Century Coupled Carbon/Climate Simulations Net CO 2 Flux (Pg C/yr) Fully prognostic land/ocn BGC and carbon/radiation Atm-Land: 70 PgC/yr  ; Atm-Ocean: 90 PgC/yr  Net Land+ocean: 0  1 PgC/yr “Stable” carbon cycle and climate over 500y Projection of climate change on natural modes Detection & attribution Surface Temp year

500+ yr of Atm CO 2 Variability Annual mean varies by ~4ppm over 500+years Surface ~1.5 ppm higher than column average Column variability ~ sfc variability Column 5y means Sfc 5y means

Land and Ocean Contributions to Globally- averaged Column CO 2 CO 2 _ land more variable (~6 ppm) than CO 2 _ ocn (~2.5 ppm) Conservation  CO 2 _ land and CO 2 _ ocn have opposite trends… Reduction of land flux  lower atm CO 2  greater oceanic outgassing But not always… Due to ocn only Due to land only

Time-evolving, 3-D Atmospheric CO 2 fields

CCSM1-Carbon Modules Spin-up Results from Control –Atm –Land –Ocean Fossil Fuel emission

Annual Net Atm-Land Flux = Net Ecosystem Production = Rh (~70 PgC/y  ) – NPP (~70 PgC/y  ) 2 PgC/yr Natural NEP Variability  “noise” for detecting anthropogenic land sink

Terrestrial Carbon Inventory Live Biomass ~ 870PgC Dead Biomass ~ 1080PgC 7 PgC 8 PgC

Variability Mechanism: e.g. Wood  /  t (WOOD) =  wood NPP – WOOD/  _wood  /  t (CWD) = WOOD/  _wood – CWD/  _cwd NPP responds to instantaneous climate  _wood fixed ~ 20 yrs  _cwd ~15y * f(soilT) * g(soil_moisture) CWD integrates over decadal climate variability

CCSM1-Carbon Modules Spin-up Results from Control –Atm –Land –Ocean Fossil Fuel emission

Ocean Carbon Cycle Variability Air-sea CO 2 Flux (Pg C/yr) global interannual variability in CO 2 flux of +/-0.3 Pg Cyr -weak Equatorial Pacific variability (biases in base state) Export Flux Fung, Doney, Lindsay & John 5000 year

Long-term Ocean Drift -Most properties relatively stable over years -Drift in Antarctic Circumpolar Current and salinity vertical redistribution (w/ corresponding drift in DIC and Alkalinity concentrations) ACC Transport Fung, Doney, Lindsay & John year Global Salinity (PSS) z year

Ocean Variability Mechanisms Particle export Air-sea flux Fresh- water mol C/m^2 Fung, Doney, Lindsay & John -Maps of annual rms (y 0-200; C4.18) -Regions of high variability in North Atlantic & Pacific, tropics and Southern Ocean -Mechanisms differ across regions

CCSM1-Carbon Modules Spin-up Results from Control –Atm –Land –Ocean Fossil Fuel emissionFossil Fuel emission

CCSM1-carbon Control and Fossil Fuel Expts Control (c4.18) 400 yr1000 yr 1) Prescribed CO 2 Emissions CO 2 /Radiation Coupling 3) Prescribed CO 2 Concentrations CO 2 /Radiation Coupling 2) Prescribed CO 2 Emissions No CO 2 /Radiation Coupling Run ensembles when feasible 100 yr c4.19

Prescribed Fossil Fuel Experiment (C4.19) Land -~1/3 of fossil fuel emissions taken up by ocean -small temperature rise (+0.25 K) -land release only somewhat larger than variability in control (~6 Pg C) Net Atm. CO year Ocean ~40 Pg C uptake ~80 Pg C build-up ~8 Pg C release

CCSM Carbon-Climate GCM’s for IPCC 2007 CCSM 1.4CASA’ OCMIP’+Fe NCAR Origin (LANL) Doney, Fung, John, Lindsay CCSM 3.?CASA’ OCMIP’+Fe IBM SP’s NCAR (ORNL, NERSC) Fung, Doney, John, Lindsay, Wehner, others? CCSM 3.?CLM3-CN Ocean Eco IBM SP’sThornton, Mahowald, Lindsay, Moore, Fung, Doney

Land, Atmosphere & and Ocean Inventories Net CO 2 Flux (Pg C/yr) Approximately stable atmosphere CO 2 concentration -Substantial variability on interannual, decadal and centennial time-scales -Redistributions from land to atmosphere as large as ~10 Pg C Land Fung, Doney, Lindsay & John 5000 year Ocean

OCMIP Biotic Model + prognostic export production iron limitation and cycling Marine BGC Module

5-y running mean;  <1 PgC/y Globally Averaged Net Surface Fluxes (land +/- 70 PgC/yr; ocean +/- 90 Pg/yr) Stable !!! Over 500+ years of integration Large interannual and interdecadal variability (~1%) in land+ocean surface fluxes “Natural” flux variability ~ contemporary carbon sink

Land BGC Module } Sfc Metab Soil Metab Sfc Struc Soil Metab Coarse Wdy Debris Sfc Microb Soil Microb SlowPassive } NPPR_h Leaf Root WoodGPPR_a allocation Based on coupling of CASA BGC & Land Biogeophysics –dynamic allocation –prognostic LAI and phenolgy H2OH2OH2OH2O Energy LAI CO 2

Multi-Century Coupled Carbon/Climate Simulations Net CO 2 Flux (Pg C/yr) Fully prognostic land/ocn BGC and carbon/radiation -“Stable” carbon cycle and climate over 200y -Projection of climate change on natural modes -Detection & attribution Surface Temp Fung, Doney, Lindsay & John year

Variability Mechanisms & Modes Fresh- water Particle export Air-sea flux Fung, Doney, Lindsay & John

Carbon/Climate Control Simulation (~100y) Surface Atm. CO Net CO 2 Flux +1.0 “Stable” carbon cycle and climate over O(100y) with fully prognostic land/ocn BGC and carbon/radiation coupling 282 Surface Temp