Land Modeling II - Biogeochemistry: Ecosystem Modeling and Land Use Dr. Peter Lawrence

Transcription

1 Land Modeling II - Biogeochemistry: Ecosystem Modeling and Land Use Dr. Peter Lawrence Project Scientist Terrestrial Science Section Climate and Global Dynamics Division (With thanks to TSS and IAM groups for their many contributions) Slide 1 - Title

2 Understanding the Land Surface in the Climate System: Investigations with an Earth System Model (NCAR CESM) The land is a critical interface through which: 1. Climate and climate change impacts humans and ecosystems and 2. Humans and ecosystems can force global environmental and climate change

3 Emitted longwave Diffuse solar Downwelling longwave Latent heat flux Sensible heat flux Community Land Model (CLM4.5) Surface energy fluxes Hydrology Biogeochemical cycles Precipitation Momentum flux Wind speed 0 u a Transpiration Evaporation Fire Photosynthesis BVOCs Autotrophic respiration Reflected solar Absorbed solar Aerosol deposition SCF Ground heat flux Soil (sand, clay, organic) Bedrock Surface water Dust Sublimation Melt Soil Aquifer recharge Water table Unconfined aquifer Throughfall Evaporation Infiltration Saturated fraction Surface runoff Sub-surface runoff Phenology Soil C/N Vegetation C/N Litterfall N mineralization Heterotrop. respiration Root litter N dep N fix N 2 O Denitrification N leaching N uptake CH 4

4 Community Land Model (CLM4) subgrid tiling structure Gridcell Landunit Glacier Wetland Vegetated Lake Columns Soil Type 1 Urban PFTs

5 Landunit Vegetated Community Land Model (CLM 4.5) subgrid tiling structure Gridcell Lake TBD MD Urban HD Glacier Crop G L UT,H,M C1I C2I V PFT1 V PFT2 C1U C2U V PFT3 V PFT4 Column Soil Roof Sun Wall Shade Wall Pervious Impervious Unirrig Irrig Unirrig Irrig PFT PFT1 PFT2 PFT3 PFT4 Crop1 Crop1 Crop2 Crop2

6 Glacier Lake Wetland Flooding River Routing Runoff Competition Crops Irrigation Vegetation Dynamics Disturbance Urban River discharge Wood harvest Land Use Change Growth G L UT,H,M C1I C2I V PFT1 V PFT2 C1U C2U V PFT3 V PFT4 Landscape-scale dynamics Long-term dynamical processes that affect fluxes in a changing environment (disturbance, land use, succession) Oleson et al. 2013, CLM4.5 Technical Description, 430 pages

7 Land Surface in the Climate System 1. Surface Energy Fluxes: - Solar Energy Fluxes (Albedo Vegetation, Snow, Soils) - Long Wave Energy Fluxes (Surface Temp & Emissivity) - Latent Heat Fluxes (Transpiration, Evaporation) - Sensible Heat Fluxes (Surface Temp & Roughness) 2. Surface Hydrology: - Rain and Snow (Vegetation, Snow Pack, Runoff) - Transpiration, Evaporation, Snow melt, Sublimation - Soil Hydrology 10 Soil Layers in CLM (Richards Eqns) - Deep Aquifer recharge and drainage (Top Model) 3. Biogeochemistry (Carbon and Nitrogen Cycles): - Plant Photosynthesis and Respiration 6 CO H 2 O + light -> C 6 H 12 O O 2 - Carbohydrates are allocated to Leaves, Roots, Wood - Leaves, roots and wood become litter, debris, soil C - Organic decomposition and fire remove carbon Slide 4 - Land Nitrogen Cover Change is cycled impacting growth and decay

8 Land Surface in the Climate System 1. Surface Energy Fluxes: - Solar Energy Fluxes (Albedo Vegetation, Snow, Soils) - Long Wave Energy Fluxes (Surface Temp & Emissivity) - Latent Heat Fluxes (Transpiration, Evaporation) - Sensible Heat Fluxes (Surface Temp & Roughness) 2. Surface Hydrology: - Rain and Snow (Vegetation, Snow Pack, Runoff) - Transpiration, Evaporation, Snow melt, Sublimation - Soil Hydrology 10 Soil Layers in CLM (Richards Eqns) - Deep Aquifer recharge and drainage (Top Model) 3. Biogeochemistry (Carbon and Nitrogen Cycles): - Plant Photosynthesis and Respiration 6 CO H 2 O + light -> C 6 H 12 O O 2 - Carbohydrates are allocated to Leaves, Roots, Wood - Leaves, roots and wood become litter, debris, soil C - Organic decomposition and fire remove carbon Slide 4 - Land Nitrogen Cover Change is cycled impacting growth and decay

9 Land Surface in the Climate System 1. Surface Energy Fluxes: - Solar Energy Fluxes (Albedo Vegetation, Snow, Soils) - Long Wave Energy Fluxes (Surface Temp & Emissivity) - Latent Heat Fluxes (Transpiration, Evaporation) - Sensible Heat Fluxes (Surface Temp & Roughness) 2. Surface Hydrology: - Rain and Snow (Vegetation, Snow Pack, Runoff) - Transpiration, Evaporation, Snow melt, Sublimation - Soil Hydrology 10 Soil Layers in CLM (Richards Eqns) - Deep Aquifer recharge and drainage (Top Model) 3. Biogeochemistry (Carbon and Nitrogen Cycles): - Plant Photosynthesis and Respiration 6 CO H 2 O + light -> C 6 H 12 O O 2 - Carbohydrates are allocated to Leaves, Roots, Wood - Leaves, roots and wood become litter, debris, soil C - Organic decomposition and fire remove carbon - Nitrogen is cycled impacting growth and decay

10 CLM allows us to do Ecosystem Modeling in a Changing World 1. Changes in Atmospheric CO 2 Impacts: - Photosynthesis rates through carbon availability - Transpiration rates through water use efficiency - Vegetation and air temperature - Rain, snow and evaporative demand through climate change with impacts on soil moisture 2. Changes in Aerosols and Nitrogen Impacts: - Direct and diffuse shortwave radiation - Nitrogen available for photosynthesis - Nitrogen available for allocating carbohydrate to plant tissues with feedbacks from canopy growth 3. Land Use and Land Cover Change Impacts: - Deforestation and Wood Harvesting - Agricultural expansion - Urbanization

11 CLM allows us to do Ecosystem Modeling in a Changing World 1. Changes in Atmospheric CO 2 Impacts: - Photosynthesis rates through carbon availability - Transpiration rates through water use efficiency - Vegetation and air temperature - Rain, snow and evaporative demand through climate change with impacts on soil moisture 2. Changes in Aerosols and Nitrogen Impacts: - Direct and diffuse shortwave radiation - Nitrogen available for photosynthesis - Nitrogen available for allocating carbohydrate to plant tissues with feedbacks from canopy growth 3. Land Use and Land Cover Change Impacts: - Deforestation and Wood Harvesting - Agricultural expansion - Urbanization

12 CLM allows us to do Ecosystem Modeling in a Changing World 1. Changes in Atmospheric CO 2 Impacts: - Photosynthesis rates through carbon availability - Transpiration rates through water use efficiency - Vegetation and air temperature - Rain, snow and evaporative demand through climate change with impacts on soil moisture 2. Changes in Aerosols and Nitrogen Impacts: - Direct and diffuse shortwave radiation - Nitrogen available for photosynthesis - Nitrogen available for allocating carbohydrate to plant tissues with feedbacks from canopy growth 3. Land Use and Land Cover Change Impacts: - Deforestation and Wood Harvesting - Agricultural expansion - Urbanization

13 Ecosystem Modeling in (CLM4 CN)

14 Ecosystem Changes In the Coupled Model Intercomparison Project 5 CMIP5 1. Changes in Atmospheric CO 2 : - Historical ( ): 285ppm 379ppm - RCP 4.5 ( ): 380ppm 538ppm - RCP 8.5 ( ): 380ppm 936ppm 2. Airborne Nitrogen Deposition: - Historical: TgN/yr - RCP 4.5: TgN/yr - RCP 8.5: TgN/yr 3. Land Use and Land Cover Change: - Historical: Crop +9.8 ; Tree -5.5; Grass km 2 - RCP 4.5: Crop -4.2 ; Tree +3.0; Grass km 2 - RCP 8.5: Crop +2.8 ; Tree -3.5; Grass km 2

15 Ecosystem Changes in CMIP5 GPP No Land Use

16 Ecosystem Changes in CMIP5 Land Cover Change

17 Ecosystem Changes in CMIP5 Ecosys C No Land Use

18 Ecosystem Changes in CMIP5 Land Cover Change

19 Ecosystem Changes in CMIP5 RCP 4.5 GPP

20 Ecosystem Changes in CMIP5 RCP 8.5 GPP

21 Ecosystem Changes in CMIP5 RCP 4.5 Ecosys C

22 Ecosystem Changes in CMIP5 RCP 8.5 Ecosys C

23 CMIP5 Land Cover Change Total Ecosystem Carbon Ecosys Carbon Transient LCC No LCC Net LCC Em CMIP5 FF Em Historical PgC PgC PgC PgC RCP PgC PgC 5.8 PgC PgC RCP PgC PgC PgC PgC

24 Landunit Vegetated Gridcell Lake TBD MD Urban HD CLM subgrid tiling structure Glacier Crop G L UT,H,M C1I C2I V PFT1 V PFT2 C1U C2U V PFT3 V PFT4 Crop Model Land Use Change Planting Leaf emergence Unirrig Irrig Unirrig Irrig Irrig / Fertilize Harvest Grain fill Crop1 Crop1 Crop2 Crop2

25 Interactive Crops in the CLM 4.5+ Following AgroIBIS (Kucharik & Brye, 2003) with new Tropical Crops (Badger & Dirmeyer 2014) Temperate corn, tropical corn, cotton, rice, sugarcane, temperate soybean, tropical soybean, spring wheat Phenology by GDD accumulators Planting, leaf emergence, grain fill, maturity, harvest C allocation + N limitation Leaf area, height, crop yield

26 Idealized CLM Crop Simulations CLM Crop Allows us to investigate: - Changes in Yield, Fertilizer and Irrigation for a Historical or for a Future crop distribution and climate time period - Break down contributions to changes by: - Cropping Area - Geographic Crop Distribution - Crop Composition - Fertilizer Application - Irrigation - Climate - Atmospheric CO 2 - Historical and SSP3 (high population growth) and RCP 8.5 (high CO 2 and climate change)

27 Global Historical Analysis (All Crops) Area, Yields, N Fert

28 Global Historical Analysis (All Crop) Yield *Constant CO 2 and Climate

29 Global Historical Analysis (By Crop) Yield

30 Global SSP3 RCP 8.5 Analysis (All Crops) Area, Yield, N

31 Global SSP3 RCP8.5 Analysis (All Crop) Yield *Constant CO 2 and Climate

32 Global SSP3 RCP 8.5 Analysis (By Crop) Yield

33 Understanding the Land Surface in the Climate System: Investigations with an Earth System Model (NCAR CESM) The land is a critical interface through which: 1. Climate and climate change, impacts humans and ecosystems and 2. Humans and ecosystems can force global environmental and climate change