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

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

Absorbed

solar

Dif

fus

e s

ola

r

Do

wn

we

llin

g

lon

gw

av

e

Reflected solar

Em

itte

d

lon

gw

av

e

Se

ns

ible

he

at

flu

x

La

ten

t h

ea

t fl

ux

ua 0

Momentum flux

Wind speed

Ground

heat flux

Evaporation

Melt

Sublimation

Throughfall

Infiltra-

tion Surface runoff

Evaporation

Transpiration

Precipitation

Heterotrop.

respiration

Photosynthesis

Autotrophic

respiration

Litterfall

N

uptake

Vegetation C/N

Soil

C/N N mineral-

ization

Fire

Surface energy fluxes Hydrology

Biogeochemical cycles

Aerosol

deposition

Soil (sand, clay, organic)

Sub-surface runoff

Aquifer recharge

Phenology

BVOCs

Water table

Soil

Dust

Saturated fraction

N dep

N fix

Denitrification

N leaching

CH4

Root litter

N2O SCF

Surface

water

Bedrock Unconfined aquifer

Community Land Model (CLM4.5)

Community Land Model (CLM4) subgrid tiling structure

Gridcell

Glacier Wetland Lake

Landunit

Columns

PFTs

Urban Vegetated

Soil

Type 1

Gridcell

Glacier Lake

Landunit

Column

PFT

Urban Vegetated

Soil

Community Land Model (CLM 4.5) subgrid tiling structure

Crop

PFT1 PFT2 PFT3 PFT4 …

Unirrig Irrig Unirrig Irrig

Crop1 Crop1 Crop2 Crop2 …

L

G

UT,H,M

C1I V

PFT4

V

PFT3

V

PFT1

V

PFT2

C1U

C2U C2I

Roof

Sun Wall

Shade

Wall

Pervious

Impervious

TBD

MD

HD

Glacier

Lake

River

Routing

Runoff

River discharge

Urban

Land Use

Change

Wood harvest

Disturbance

Vegetation

Dynamics

Growth

Competition Wetland

Crops

Irrigation Flooding

Landscape-scale dynamics

Long-term dynamical processes that affect

fluxes in a changing environment

(disturbance, land use, succession) L

G

UT,H,M

C1I V

PFT4

V

PFT3

V

PFT1

V

PFT2

C1U

C2U C2I Oleson et al. 2013, CLM4.5 Technical Description, 430 pages

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 CO2 + 6 H2O + light -> C6H12O6 + 6 O2

- 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 Slide 4 – Land Cover Change

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 CO2 + 6 H2O + light -> C6H12O6 + 6 O2

- 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 Slide 4 – Land Cover Change

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 CO2 + 6 H2O + light -> C6H12O6 + 6 O2

- 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

Slide 4 – Land Cover Change

Land Surface in the Climate System

1. Changes in Atmospheric CO2 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

Slide 4 – Land Cover Change

CLM allows us to do Ecosystem Modeling

in a Changing World

1. Changes in Atmospheric CO2 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

Slide 4 – Land Cover Change

CLM allows us to do Ecosystem Modeling

in a Changing World

1. Changes in Atmospheric CO2 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

Slide 4 – Land Cover Change

CLM allows us to do Ecosystem Modeling

in a Changing World

Ecosystem Modeling in (CLM4 CN)

1. Changes in Atmospheric CO2: - Historical (1850 – 2005): 285ppm – 379ppm - RCP 4.5 (2006 – 2100): 380ppm – 538ppm - RCP 8.5 (2006 – 2100): 380ppm – 936ppm

2. Airborne Nitrogen Deposition: - Historical: 19 – 65 TgN/yr - RCP 4.5: 65 – 55 TgN/yr - RCP 8.5: 65 – 85 TgN/yr

3. Land Use and Land Cover Change: - Historical: Crop +9.8 ; Tree -5.5; Grass -3.3 106 km2 - RCP 4.5: Crop -4.2 ; Tree +3.0; Grass +1.0 106 km2 - RCP 8.5: Crop +2.8 ; Tree -3.5; Grass +0.9 106 km2

Slide 4 – Land Cover Change

Ecosystem Changes In the Coupled Model

Intercomparison Project 5 – CMIP5

Slide 4 – Land Cover Change

Ecosystem Changes in CMIP5 – GPP No Land Use

Slide 4 – Land Cover Change

Ecosystem Changes in CMIP5 – Land Cover Change

Slide 4 – Land Cover Change

Ecosystem Changes in CMIP5 – Ecosys C No Land Use

Slide 4 – Land Cover Change

Ecosystem Changes in CMIP5 – Land Cover Change

Slide 4 – Land Cover Change

Ecosystem Changes in CMIP5 – RCP 4.5 GPP

Slide 4 – Land Cover Change

Ecosystem Changes in CMIP5 – RCP 8.5 GPP

Slide 4 – Land Cover Change

Ecosystem Changes in CMIP5 – RCP 4.5 Ecosys C

Slide 4 – Land Cover Change

Ecosystem Changes in CMIP5 – RCP 8.5 Ecosys C

Slide 4 – Land Cover Change

CMIP5 Land Cover Change – Total Ecosystem Carbon

Ecosys Carbon Transient LCC No LCC Net LCC Em CMIP5 FF Em

Historical -61.3 PgC +68.4 PgC 129.7 PgC 313.8 PgC

RCP 4.5 +62.8 PgC +68.6 PgC 5.8 PgC 791.5 PgC

RCP 8.5 -43.4 PgC +119.8 PgC 163.2 PgC 1925.0 PgC

Gridcell

Glacier Lake

Landunit

Urban Vegetated Crop

Unirrig Irrig Unirrig Irrig

Crop1 Crop1 Crop2 Crop2 …

L

G

UT,H,M

C1I V

PFT4

V

PFT3

V

PFT1

V

PFT2

C1U

C2U C2I

TBD

MD

HD

Land Use

Change

Planting

Leaf

emergence

Grain fill Harvest

Crop Model

Irrig /

Fertilize

CLM subgrid tiling

structure

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

Slide 4 – Land Cover Change

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 CO2

- Historical and SSP3 (high population growth) and RCP 8.5 (high CO2 and

climate change)

Slide 4 – Land Cover Change

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

Slide 4 – Land Cover Change

Global Historical Analysis (All Crop) Yield

*Constant CO2 and Climate

Slide 4 – Land Cover Change

Global Historical Analysis (By Crop) Yield

Slide 4 – Land Cover Change

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

Slide 4 – Land Cover Change

Global SSP3 RCP8.5 Analysis (All Crop) Yield

*Constant CO2 and Climate

Slide 4 – Land Cover Change

Global SSP3 RCP 8.5 Analysis (By Crop) Yield

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