making the case for coupled chemistry, climate, biogeochemistry simulations e.a. (beth) holland...
TRANSCRIPT
Making the case for coupled chemistry,
climate, biogeochemistry simulations
E.A. (Beth) HollandChemistry-Climate Workshop
Santa Fe, NM, Feb. 10-12
Thank you!
Roadmap• Carbon cycle
• Carbon/Nitrogen Cycle
• CN Chemistry
• CN Chemistry Climate
• CN Chemistry Climate Biogeochemistry
Summary for Policymakers, IPCC 2001
Table 3.1: Global CO2 budgets (in Pg C/yr) based on intra-decadal trends in atmospheric
CO2 and O2. IPCC 2001, Prentice et al, Chapter 3
1980s 1990s
Atmospheric increase
3.3 ± 0.1 3.2 ± 0.1
Emissions (fossil fuel, cement)
5.4 ± 0.3 6.3 ± 0.4
Ocean-atmosphere flux
-1.9 ± 0.6 -1.7 ± 0.5
Land atmosphere flux*
-0.2±0.7 -1.4±0.7
Land use change 1.7 (0.6 to 2.5) NA
Residual terrestrial sink -1.9 (-3.8 to 0.3)
NAPositive values are fluxes to the atmosphere; negative values represent uptake from the atmosphere. The fossil fuel emissions term for the 1980s (Marland et al., 2000) has been slightly revised downward since the SAR. Error bars denote uncertainty (± 1s), not interannual variability, which is substantially greater.
Atmosphere photosynthesis & respiration
plants etc.
soil (microbes, roots)
Biosphere(C, H2O, N…)O2CO2
O2
O2
CO2
CO2
Pedosphere
H2O
NOy
NOx
Norg
NO3-
N2
NH4+
Norg
NO, N2O
NO2
Coupling C and N
Vegetation Type
Fractionwood
C:Nmicrobes
C:Nleaves
C:N wood
Tropical rainforest
0.5 14 50 150
TemperateEvergreen forest
0.5 14 70 300
Shrubland 0.5 14 60 180Grassland 0 10 55 0
What are the implications of N depositionfor the global carbon cycle?
Table 6. Comparison of Terrestrial Net CO2 Flux Estimated by InverseDeconvolution and Our Perturbation Estimate of Terrestrial Net CO2 Flux from NDeposition
90°S–16°S Equatorial 16°N–90°N
Global
Keeling et al. [1989] a -0.1 +0.3 -0.6 -0.5
Tans et al. [1994] a -0.1 +0.5 -2.3 -1.9
Ciais et al. [1995] b -0.2 +0.8 -2.2 -1.5
With SaturationThis work
IMAGES c -0.04 -0.11 -0.38 -0.53
ECHAM c -0.05 -0.16 -0.41 -0.62
GCTM c -0.06 -0.13 -0.37 -0.56
GRANTOUR c -0.04 -0.11 -0.36 -0.51
MOGUNTIA c -0.05 -0.16 -0.40 -0.61
MOGUNTIA NHx + NOyd -0.10 -0.26 -0.73 -1.09
Without SaturationThis work
IMAGES c -0.04 -0.12 -0.57 -0.73
ECHAM c -0.05 -0.19 -0.73 -0.97
GCTM c -0.07 -0.15 -0.73 -0.95
GRANTOUR c -0.04 -0.12 -0.50 -0.66
MOGUNTIA c -0.06 -0.20 -0.64 -0.90
MOGUNTIA NHx + NOy
d-0.11 -0.29 -1.02 -1.42
Values are in units of Gt C yr-1.aBased on CO2 concentrations.
bBased on 13CO2 + CO2.cIncludes NOy deposition from fossil fuel combustion and 50% of nonfossil fuel NOy.dIncludes NOy deposition from fossil fuel combustion and 50% of nonfossil fuelNOy plus 50% of NHx deposition.
Wet deposition of NH4
+Wet deposition of
NO3-
Dry deposition of particulate NH4+
Dry deposition of HNO3 (g)
Dry deposition of particulate NO3
-
Holland, Braswell, Sulzman, Lamarque submitted
All units kg N ha-1 y-1
How does N retention vary with N deposition?
Holland, Braswell and Bossdorf
How does N deposition impact C storage across a range of vegetation types?
Do these simulations provide any evidence of N saturation characterized by a non-linear
increase in outputs relative to inputs?
Holland, Braswell and Bossdorf, in prep.
N lossesConiferous Forests current N deposition 4.71
10X 29.78Deciduous Forests Current N deposition 5.21
10X 32.14Mixed Forests Current N deposition 4.80
10X 30.82Shrublands Current N deposition 1.50 10X 10.75Savannas Current N deposition 8.78 10X 55.94Grasslands Current N deposition 5.77 10X 39.14
NO!
N losses=gaseous losses (NO + NH3 +N2O+ nitrate leaching, kg N ha-1 y-1
Figure 4: The correlation between NOy deposition and surface ozone concentrations predicted by IMAGES, a 3-D chemical transport model. The correlation occurs because both depend on the same sets of chemical reactions, precursors. (from Holland et al 1997, JGR Atmospheres 102:15,849-15,866).
What’s missing?
Vegetation Dynamics
0
0.3
-10 25 60Temperature (C)
g C
O2g
-1s
-1 Root
HeterotrophicRespiration
Ecosystem Carbon Balance
Growth Respiration
g C
O2g
-1s
-1
0 1 2
Foliage Nitrogen (%)
0 15 30
Temperature (C)
g C
O2g
-1s
-1
0 500 1000
Ambient CO2 (ppm)
Photosynthesis
0 -1 -2
Foliage Water Potential (MPa)
g C
O2g
-1s
-1
0 1500 3000
Vapor Pressure Deficit (Pa)
46
20
0 500 1000
PPFD (molm-2s-1)
46
20
46
20
Sapwood
0
0.01
-10 25 60Temperature (C)
g C
O2g
-1s
-1Foliage
0
0.5
-10 25 60Temperature (C)
g C
O2g
-1s
-1
0 15 30Temperature
(C)
Re
lativ
e R
ate
1
8
Soil Water (% saturation)
Re
lativ
e R
ate
0 1000
1
AutotrophicRespiration
Litterfall
NutrientUptake
Community Land ModelDynamic Vegetation
Bonan 2002
Vegetation Dynamics
Species compositionEcosystem structureNutrient availability
Minutes-To-Hours
Days-To-Weeks
Years-To-Centuries
HeatMoistureMomentum
ClimateTemperature, Precipitation,Radiation, Humidity, Wind
ChemistryCO2, CH4, N2O
Ozone, Aerosols
CO2, CH4
N2O, Dust,Volatile organic compounds
Physiology Phenology Ecosystems
Ecosystems
• Carbon uptake• Carbon loss• Nutrient uptake• Allocation
• Bud break• Leaf drop
• Litterfall• Decomposition• Mineralization• Soil chemistry
Watersheds• Evapotranspiration• Interception• Infiltration• Runoff• Snowmelt
Aer
o-dy
nam
ics
Biogeophysics
Ene
rgy
Wat
er
Ecosystem Processes
Plant Demography
Old-Growth Forest
DisturbanceFiresHurricanesLand useInvasive species
Open Site
Surface Fluxes
Ele
men
t C
ycle
s
Biogeochemistry
Can
opy
Phy
siol
ogy
Soi
l P
roce
sses
Soil water, snowpack Leaf area, leaf nutrition
Integrator Of Processes And Time-Scales
Bonan (2002) Ecological Climatology. Cambridge Univ. Press
Community Land Model
BASE CASE EMISSIONS from MOZART 2 (JULY)
IsopreneFlux
NO flux
Weidenmyer, C, XX Tie, S. Levis, A. Guenther, and EA Holland
What is the impact of land use change on global O3
concentrations?Change in Concentration (ppbv)
% Change
•For 25% of each grid cell in the Amazon basic, isoprene flux is increased by a factor of 8, replacement with oil palm plantations
•For 25% of each grid cell in the northwest U.S., isoprene flux is increased by a factor of 30, replacement with Poplar plantations
Weidenmyer, C, XX Tie, S. Levis, A. Guenther, and EA Holland
The GLOBAL N CYCLE
Putting the pieces together
Sellers et al 1997, Science
Stomatal Stomatal conductanceconductance
N interactions
• Dickinson, R.E., J. A. Berry, G. B.Bonan, G. J. Collatz, C. B. Field, I. Y. Fung, M. Goulden, W. A. Hoffman, R. B. Jackson, R. Myneni, P. J. Sellers and M. Shaikh, 2001: Nitrogen Controls on Climate Model Evapotranspiration. J Clim., 15, No. 3, 278-295.
RESULT: Improvements in models ability to capture
the seasonal cycle of temperature.
What if?
We included N, CO2 and O3 feedbacks on stomatal conductance and the influence of stomatal conductance on dry deposition?
Comparison of the five models: dry deposition velocitiescm s-1
ECHAM1 GCTM2 GRANTOUR3 IMAGES4 MOGUNTIA5
O3 0.4 n/ a 0.6 0.4 grasslands0.5 savannah
1 tropical forests0.6 other forests
0.35
NO 0.04 0.25 0.10 0.6 * Vd for O3 0.40
NO2 0.25 0.25 0.50 0.6 * Vd for O3 0.25
HNO3 2.0 1.5 1.0 2.0 2.0
1 Roelofs and Lelieveld 19952 Kasibhalta et al. 1991, 1993; Levy et al. 1996 a & b; Moxim et al. 19963 Penner et al. 1991; 19934 Müller 1992; Müller and Brasseur 1995; Lamarque pers. comm.5 Dentener and Crutzen 1993
Deposition Velocity Calculation
Fc = Vd * CFc- flux, Vd- deposition velocity, C-
concentration
Vd =(Ra + Rb + Rs) –1
Ra-aerodyamic resistance, from CLMRb-quasi-boundary layer resistance, from CLM
Rs-surface resistanceapproach of Ganzeveld (1995, 1999) + Wesley and Hicks 2000
HNO3 drydeposition(kg N ha-1 y-1)
QuickTime™ and aYUV420 codec decompressorare needed to see this picture.
0.30
0.75
.0
0.0
1.51
0.61
Holland, EA, JF Lamarque, J Sulzman, R. Braswell, submitted, Global Biogeochemical Cycles
conterminous United States,
total measured N deposition= 4.54 Tg N y-1
28%
26%
24%
22%NO3-(aq)
NOy(g+particulate)
NH4+(aq)
NH4+(particulate)
NO3-(aq)
NOy (g+particulate)
NH4+
(aq)
NH4+
(particulate)
Western Europe,
total measured N deposition= 10.83 Tg N y-1
21%
11%
36%
12%
20%
NO3-(aq)
HNO3(g)+NO3-(particulate)NO2(g)
NH4+(aq)
NH4+(particulate)
NO3-(aq)
HNO3 (g)+NO3-(particulate)
NO2 (g)
NH4+
(aq)
NH4+
(particulate)
Global NOy deposition budget, from TM3, total N deposition=46.4 Tg N y-1
14%
44%
6%
5%8%
23%
NOx(g)
HNO3(g)
HNO3(aq)
organic nitrates (g)
PAN (g)
organic nitrates (aq)
NOx (aq)
HNO3 (g)
HNO3 (aq)
Organic Nitrates (g)
PAN (g)
Organic Nitrates (aq)
N deposition partitioning for two measurement compilations (Holland et al. submitted) and one model compilation (Neff et al. 2002)
Wet deposition of NH4
+Wet deposition of
NO3-
Dry deposition of particulate NH4+
Dry deposition of HNO3 (g)
Dry deposition of particulate NO3
-
Holland, Braswell, Sulzman, Lamarque submitted
All units kg N ha-1 y-1
Atmosphere photosynthesis & respiration
plants etc.
soil (microbes, roots)
Biosphere(C, H2O, N…)O2CO2
O2
O2
CO2
CO2
Pedosphere
H2O
NOy
NOx
Norg
NO3-
N2
NH4+
Norg
NO, N2O
NO2
Coupling C and N
Vegetation Type
Fractionwood
C:Nmicrobes
C:Nleaves
C:N wood
Tropical rainforest
0.5 14 50 150
TemperateEvergreen forest
0.5 14 70 300
Shrubland 0.5 14 60 180Grassland 0 10 55 0
P. Thornton, NCAR/CGD, Sept. 2002
NOx flux = Fw/ d ( T, Aw/ d) x P x CR (LAI, SAI)(ng m-2 s-1)
T-soil temperatureA-biome dependent coefficientw/ d - distingushes between wet and dry soil fluxes
for wet soils, there are 3 temperature relationships:
cold ( 0-10 °C): = 0.28 x Aw x T (a)normal (10-30 °C): = Aw x e (0.103+0.04) x T (b)
optimal (>30 °C) = 21.97 x Aw (30° substituted into b)
for dry soils, there are 2 temperature relationships:
cold (0-30 °) =Ad x T / 30°optimal (> 30° C) = Ad
P- precipitation scalar factor to adjust the flux in event of a flux depending on one of the following four states:
no rain:P=1.0
sprinkle: 0.1 < rain < 0.5 cm day-1, 5 fold increase
P= 11.19 x e -0.805 [day-1] x t (1< time (days) <3)
shower: 0.5 < rain < 1.5 cm day-1 10 fold increase
P= 14.68 x e -0.384 [day-1] x t (1< time (days) <7)
heavy rain: 1.5 < rain cm day-1 15 fold increase
P= 18.46 x e -0.208 [day-1] x t (1< time (days) <14)
pulse yield: 1.3 Tg NOx-N y-1
Soil NO flux Yienger and Levy
Soil N gas model
Model measurement Model measurement comparisoncomparison
Parton,1, W.J., E.A. Holland,2 S.J. Del Grosso,1 M.D. Hartman,1 R.E. Martin,3 A.R. Mosier,4 D.S. Ojima,1 and D.S. Schimel2. Generalized Model for NOx and N2O Emissions from Soils. J. Geophys. Res . 106:17,403-17,419.
What is the acceleration of the N cycle?
How has the quantity and pattern of N deposition changed over the last 100 years?
N forcing
Summary for Policymakers, IPCC 2001
Compound Average RangeGreenhouse gases
CO2-fossil fuel +167% (-28 to +405)CH4 +62 (-24 to 137)N2O +44 (-19 to 148)
O3 precursors C: NMVOCs + CO +85% (-59 to 202) N: NOx +98% (-39 to 192)
Sulfate aerosolprecursors
SO2 -48 (-15 to –72)
What does the future hold ?
IPCC SRES scenario emissions: % increases projected for 2100, relative to 2000
The NCAR Biogeosciences Initiative:
Elisabeth Holland (Program Leader)
Gordon Bonan
Alex Guenther
Natalie Mahowald
David Schimel
Britton Stephens
Jielun Sun
Peter Thornton
0
2
4
6
8
300 yr 4.1 million yr
NO
3-N
ug
/g
0
20
40
60
80
100
300 yr 4.1 million yr
Net
Nit
rifi
cati
on
/Net
M
iner
aliz
atio
n %
0
0.5
1
1.5
2
2.5
300 yr 4.1 million yrN2O
-N a
nd
NO
-N n
g c
m-2
h-1
NO
N2O
Nitrate ConcentrationNet Nitrification
(% Net Mineralization) N Trace Gases
Abiotic controls on nitrification
Regulation of NO:N2O
ratio