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Mathematical Models of Dynamics and Control of Environmental Changes: Scaling from Genomes to Ecosystems Shanghai, China. April 26 - May 1, 2009. Integrated Assessment Modeling of Biogeochemical Cycles, Climate Change and Impacts. Atul Jain Department of Atmospheric Sciences
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Mathematical Models of Dynamics and Control of Environmental Changes: Scaling from Genomes to Ecosystems Shanghai, China. April 26 - May 1, 2009 Integrated Assessment Modeling of Biogeochemical Cycles, Climate Change and Impacts Atul Jain Department of Atmospheric Sciences University of Illinois, Urbana, IL 61801 Email: jain1@uiuc.edu
Development of Climate Models Over the Last Three Decades Nitrogen Cycle Human Dimension
Future Projections Based on ISAM • Major Uncertainties • Carbon Cycle (Resulting CO2 Concentration) and • Climate Sensitivity (ºC for 2CO2) IPCC (2001)
Global Ocean and Atmosphere Model (0-d, 1-d, 2-d, 3-d….) Longwave Radiation Atmospheric CO2 Shortwave Radiation Temperature Respiration Boundary Layer Conductance Sensible Heat Photosynthesis Transpi-ration Stomatal Conductance Cloud Formation Instability Biomass Shoot Growth Atmospheric Moisture Evapo-ration Root Water Uptake Albedo Root Growth Precipitation Soil Moisture Streamflow River CO2 Soil Carbon
Scaling Issues Data Limitations Synergistic Effects Computational Resources Process Level Understand at the Global Scale Process Level Understand at the Local Scale
Integrated Science Assessment Modeling (ISAM) EMISSIONS Socio-economic + energy analyses and modeling CONCENTRATIONS Carbon Cycle & Chemical transport models RADIATIVE FORCING Radiative transfer models CLIMATE CHANGE A-O-CIRCULATION A-O Models IMPACTS
Soil1500 Plant500 ? ? ? Climate Change ? Nitrogen Phosphorus The Global Carbon Cycle - 1990sUnits: Pg C and Pg C y-1 Atmosphere730 3.2 Fossil fuels 63 4130 6.3 60 Fossil emission 1.7 90 92 Land Use Ocean 38,000 IPCC (2001)
Interactions of Human Related Disturbances with Terrestrial Ecosystems CO2 Climate Terrestrial Ecosystems Nitrogen Deposition Land use change Biomass Burning Biogenic Emission
DJF JJA Terrestrial Ecosystems and Chemistry Isoprene Emissions (Year 2000) (mg C/m2/month) Summer DJF DJF JJA DJF JJA Tao & Jain (JGR, 2005)
CO2 Emissions from Open Fire Open Fire Area BurnedYear 2000 (million km2) Open Fire CO2 EmissionsYear 2000 (gC/m2/yr) Jain et al. (JGR, 2006)
Sequestering Carbon in Terrestrial Ecosystems:No Tillage (NT) Agriculture Practices Small changes can lead to large benefit +63 GtC/y -60 GtC/y • Multiple benefits • Reduced erosion • Improved soil fertility • Increased water retention • Conserved energy • Saved labor cost • Increased crop yield • Increased carbon storage Respiration
Modeled Soil Carbon Sequestration Potential (Conventional Tillage to No Tillage) Averaged Over the Period 1981-2000(MgC/ha/yr) Jain et al. (GRL, 2005)
Percent (%) Change in Soil Carbon Sequestration due to Changes in Climate & CO2 Positive (negative) values indicate an increase (decrease) in soil C sequestration potential due to changes in climate, land use and CO2. Jain et al. (GRL, 2005)
1765 Pre-industrial(1765) Current (2000) 2000 Direct Implications of Human Activities Ramankutty et al. Galloway et al. (2004) Land Cover and land Use Changes for Cropland Nitrogen Deposition as a result of Fossil Fuel Burning and Fertilizer applications
Research Questions? • What are the relative contributions of • Land use • Natural ecosystem dynamics • fire • Climate variability • N deposition • Hydrology on carbon and Nitrogen dynamics and atmospheric chemistry? • What are their synergistic effects? • What are their potential future trends?
Hierarchy of ISAM Terrestrial Model Jain et al. (1997) Jain and Yang (2005)
Global Terrestrial C-N ISAM Yang et al. (2009)
Tropical Evergreen Tropical Deciduous Temperate Evergreen Temperate Deciduous Boreal Forest Savanna Grassland Shrubland Tundra Desert Polar Desert Cropland Pasture Global Terrestrial C-N ISAM 1-D → 2-D | 0.5o → 0.1o Biome Types • 13 Biome types • 0.5 x 0.5 degree resolution • Carbon cycle • Nitrogen cycle • Feedbacks: Climate-C-N-LUC… Jain and Yang (2005,GBC)
Model Calibration • Long-term Inter-site Decomposition Experiment (LIDET) and other site-specific data • Leaf, wood and root litter decomposition data • C:N • Lignin:N • Climate Yang et al. (2008)
N amount required for predicted C storage amount Why Model Terrestrial Nitrogen Cycle? Models predict the carbon uptake under rising carbon dioxide and changing climate Study suggests that the available N amount is insufficient to sustain the estimated carbon uptake. Hungate et al.2003 Science
Terrestrial Biosphere Responses to CO2 Increase & Climate Change Carbon and Nitrogen Interaction Climate, Carbon and Nitrogen Interaction
ISAM Simulations • ISAM run to equilibrium with [CO2] ~ 280 ppm and climate for early 1900s • Five scenarios examined with and without N dynamics (1765-2000): • Increasing CO2 (~370 ppm by 2000) • Climate variability (Temp. and Precip.) • Increasing CO2 + Climate variability • Changes in N deposition • Changes in land cover and land use
ISAM Simulations • Without N dynamics (Case C): • N availability held constant at preindustrial levels • With N dynamics (Case NC): • N allowed to vary according to fully dynamic N cycle Model accounts for the effect of available mineral N on NPP and soil decompositions • Two time periods: 1900-2000, 1990’s
Response to Increasing CO2 • Terrestrial ecosystems are a net sink in both cases • Inclusion of N dynamics reduces CO2 fertilization effect • Without new N inputs mineral N available for plants declines
(gC/m2/yr) N dynamics – N unchanged: CO2 effect on C flux (1990s)
Impact of Climate on Terrestrial Carbon Storage • Biosphere is a source under climate with increasing temperatures • Less of a source with N dynamics • Increased mineral N
(gC/m2/yr) N dynamics – N unchanged: Climate effect on C flux (1990s)
Response to Increasing CO2 & Climate Change • CO2 effect reduces net C storage • Climate introduces interannual variability and reduces net C release • Combined effect does not show any impact on C storage CO2 Climate CO2 + Climate 1990s
Carbon Carbon-Climate Carbon-Climate Interaction Land CO2 Storage
Carbon Carbon-Nitrogen Carbon-Nitrogen Interaction Land CO2 Storage
Carbon Carbon-Nitrogen Climate Carbon-Nitrogen Carbon-Nitrogen-Climate Interaction Land CO2 Storage
Carbon Carbon-Nitrogen Climate Carbon-Climate Carbon-Nitrogen Carbon-Nitrogen-Climate Interaction Land CO2 Storage
N dynamics – N unchanged: Climate & CO2 effect on C flux (1990s) (gC/m2/yr) CO2 Climate CO2 & Climate
N dynamics – N unchanged: N Deposition and LUC effect on C flux (1990s) (gC/m2/yr) (gC/m2/yr) Land cove changes for cropland leads to additional terrestrial carbon source N deposition leads to additional terrestrial carbon sink
Nitrogen Deposition - Fossil Fuel Burning & N Fertilizer 1900 2000 Galloway et al. (2004)
N Deposition Effect on C Storage (1990s) N deposition leads to additional terrestrial carbon sink
Combined effect leads to a negligible impact on net terrestrial carbon uptake Terrestrial Response to Changes in CO2, Climate, LUC, N Deposition
Conclusions - C-N Modeling • On a global scale combined effect results in a negligible impact on net terrestrial carbon flux. • Carbon-only models will overestimate CO2 fertilization sink in subtropics and climate induced source in high latitude regions.
Conclusions • Earth System approach is needed to improve the understanding the climatic impact of non-CO2 greenhouse gases • Interaction of various component of the Earth system affect the ability to address issues related to climate protection
Estimation of Carbon Emissions from Land-Use Changes and Net Carbon Storage/Release AcrossMonsoon Asian Region C sources or release (+) and sinks or storage (-)
Changes in Land Use • Changes in area • Croplands (clearing and abandonment) • Pastures • Wood harvest & recovery (primary and secondary forest) • Changes in carbon stocks • Fire • Management practices (e.g., no tillage, biofuels)
Estimated CO2 emissions due to Land Use Changes for the 1990s FAO Satellite gCm-2yr-1
Land Use Changes - Croplands (2000) Houghton (2008) HYDE Ramankutty