john kimball faithann heinsch steve running ntsg univ. of montana march 28, 2006
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Arctic RIMS & WALE(Regional, Integrated Hydrological Monitoring System &
Western Arctic Linkage Experiment)
John Kimball
FaithAnn Heinsch
Steve Running
NTSG Univ. of Montana
March 28, 2006
http://rims.unh.edu/data.shtml
http://wale.unh.edu/
Arctic RIMS & WALE(Regional, Integrated Hydrological Monitoring System &
Western Arctic Linkage Experiment)
Biome-BGC v.4.1.2
Inputs (25-km resolution):
• Meteorology– NCEP, 1980-2002
• Elevation– GTOPO
• Soils– FAO Soil Texture– Rooting Depth http://rims.unh.edu/data.shtml
http://wale.unh.edu/
Arctic RIMS & WALE(Regional, Integrated Hydrological Monitoring System &
Western Arctic Linkage Experiment)
Biome-BGC Land Covers:
• C3 Grass• Deciduous Broadleaf Forest• Deciduous Needleleaf Forest• Boreal Evergreen Needleleaf Forest
• Sedge (moist) Tundra• Tussock (dry) Tundra)
Biome-BGC Tundra EcophysiologyParameter C3 Grass Tussock Tundra Sedge Tundra
Whole Plant Mortality Fraction 0.05 0.01 0.01
Fire Mortality Fraction 0.01 0.002 0.002
New fine root C : New leaf C 2.0 2.5 1.5
C:N of leaves 28.1 30.0 25.0
C:N of leaf litter, after translocation 45.8 91.7 33.5
C:N of fine roots 50.0 50.0 37.0
Leaf litter labile /cellulose/lignin proportion
0.39 / 0.44 / 0.17 0.39 / 0.44 / 0.17 0.51 / 0.44 / 0.05
Fine root labile /cellulose/lignin proportion
0.68 / 0.23 / 0.09 0.30 / 0.45 / 0.25 0.80 / 0.12 / 0.08
Canopy water interception coeff. 0.01 0.021 0.021
Canopy light extinction coeff. 0.48 0.6 0.6
Specific leaf area 65.0 45.0 45
Fraction of leaf N in Rubisco 0.32 0.20 0.20
Maximum stomatal conductance 0.006 0.005 0.005
Cuticular conductance 0.00006 0.00001 0.00001
Leaf water potential: start of / complete conductance reduction
-0.73 / -2.70 -0.7 / -3.5 -0.7 / -3.5
VPD: start of / complete conductance reduction
1000 / 5000 930 / 4100 930 / 4100
Wetland-BGC
• Has a 2-layer soil model:– Unsaturated & saturated layers– Dynamic changes (3 cases)
• No saturation of rooting depth• Partial saturation of rooting depth• Total saturation of rooting depth
• Provides water from saturated layer using capillary rise function from latest version of RHESSys (based on principles of hydraulic conductivity & depth to saturation)
• At present, only affects carbon pools
Year Tower Biome-BGC1999 -0.75 (+1.77) -0.24 (+0.37)2000 -0.37 (+0.62) -0.01 (+0.55)2001 -0.51 (+0.72) +0.17 (+0.47)
Average Summer NEE (gC m-2 d-1)
Date
1/1/2000 4/1/2000 7/1/2000 10/1/2000 1/1/2001
NE
E (
gC
m-2
d-1
)
-3.0
-2.0
-1.0
0.0
1.0
2.0
3.0
Tower
Biome-BGC, gwd = 5 cm
C source (+)
C sink (-)
20002000
Date
1/1/2001 4/1/2001 7/1/2001 10/1/2001 1/1/2002
NE
E (
gC
m-2
d-1
)
-3
-2
-1
0
1
2
3
Tower
Biome-BGC, gwd = 5 cm
C source (+)
C sink (-)
20012001
NEE: Biome-BGC vs. Tower, Barrow, AKNEE: Biome-BGC vs. Tower, Barrow, AK
gwd = 0 cmgwd = 1 cmgwd - 5 cmgwd = 10 cmgwd = 20 cmgwd = 50 cm
Julian Day
1/1/1995 7/1/1995 1/1/1996
Cu
mu
lati
ve N
EE
(gC
m-2
)
-60
-40
-20
0
20
40
Date
1/1/1995 7/1/1995 1/1/1996
Air
Tem
per
atu
re
-50
-25
0
25
Precip
itation
(cm)
0
2
4
6
8
Wet Sedge Wet Sedge Tundra: Tundra:
Barrow, AK, 1995Barrow, AK, 1995Varying Varying
Groundwater Groundwater Depth (gwd)Depth (gwd)
Year
1970 1975 1980 1985 1990 1995 2000 2005
Annual P
recipitation (cm)
0
5
10
15
20
25
Ave
rage
Day
time
Tem
pera
ture
(de
g C
)
-20.0
-17.5
-15.0
-12.5
-10.0
-7.5
-5.0
PrecipitationTemperature
Year
1970 1975 1980 1985 1990 1995 2000 2005
NP
P (
gC m
-2 y
-1)
100
150
200
250
300
Year
1970 1975 1980 1985 1990 1995 2000 2005
So
il C
arb
on
Po
ol (
gC m
-2)
114.82
114.84
114.86
114.88
114.90NPP and Soil Carbon, Barrow TowerNPP and Soil Carbon, Barrow Tower
Biome-BGC ResultsBiome-BGC Results
Julian Day
0 60 120 180 240 300 360
Cu
mu
lati
ve N
PP
(gC
m-2
d-1
)
0
50
100
150
200
250
300
Average1956 - minimum productivity1998 - maximum productivity
Julian Day
0 60 120 180 240 300 360
Cu
mu
lati
ve N
EE
(gC
m-2
d-1
)
-30
-20
-10
0
10
20
30
40
C source (+)
C sink (-)
BarrowBarrow
Julian Day
0 60 120 180 240 300 360C
um
ula
tive
NP
P(g
C m
-2 d
-1)
0
50
100
150
Average1993 - minimum productivity1989 - maximum productivity
Julian Day
0 60 120 180 240 300 360
Cu
mu
lati
ve N
EE
(gC
m-2
d-1
)
-30
-20
-10
0
10
20
30
40
C source (+)
C sink (-)
AtqasukAtqasuk
ConclusionsConclusions• Spatial and temporal patterns of tundra NEE and component
photosynthetic and respiration processes are strongly regulated by soil moisture.
• Interannual variability in vegetation productivity and net C exchange is on the order of 99% (15.9 gC m-2 y-1) and 19% (37.3 gC m-2 y-1), respectively.
• Soil heterotrophic respiration is a large component of pan-Arctic NEE.
• Moderate decreases in groundwater depth promote soil decomposition and respiration during the growing season, but increased respiration is partially offset by increased vegetation productivity.
• The tundra carbon cycle response to climate change appears to be non-linear and strongly coupled to surface hydrology and nitrogen availability.
AMSR-E Daily Tb (L2A Product)
Daily Surface Temp. (Ts)in o C
Daily Surface Soil Moisture(mv) in %
8-Day Composite temporalTs and mv
Arctic Land CoverMap
Arctic Biome Property LUTSLA, Kltr,mx, Ksoil,mx
MODIS Monthly Max. LAIComposites LAImx, LAIgs,mn
MODIS SpatialResampling
MODIS 8-Day NPP(NPP8-day)
MODIS Annual NPP(NPPann)
Multipliers (Wmult, Tmult) Class-specific rate curves
mv Ts
Klit,adj = Klit,mx * Wmult * TmultKsoil,adj = Ksoil,mx * Wmult * Tmult
Litterfall=2.22 (LAImx - LAIgs,mn) * SLA-1
Clitr = (LAImx - LAIgs,mn) * SLA-1
Rh,8-day=(Clai*Klaiadj )+(Clitr*Klitr,adj)+(Csoil*Ksoil,adj)
Arctic ActiveLayer
Soil C poolMap (Csoil)
NEE8-day = (NPP8-day - Rh,8-day) Rh,ann= (Rh,8-day)i
NEEann = (NPPann - Rh,ann)
Satellite-based mapping and monitoring of Pan-Arctic Rh, NEE and surface soil temperature andmoisture controls to CO2 respiration.
45
1i
Wmult Tmult
Land surface temperature derived using AMSR-E 6.9 GHz H and V Polarization. We also have compared the differences among different approaches and channels and MODIS Aqua LST, The atmospheric effect, in emissivity vary differently depending on the channels. In the arctic environment, the upper layers of soil are frozen, and the thermal inertia of below-ground (permafrost) effect develops low soil temperature. Our model produces reliable soil temperature using microwave data. AMSR-E 6.9 and 36.6 GHz channels are sensitive to temperature change.
AMSRE 6.9 GHz Land Surface Temperature (LUT) on May 25, 2003
240
250
260
270
280
290
300
1/1 2/10 3/21 4/30 6/9 7/19 8/28 10/7 11/16 12/26
Date
So
il T
em
pe
ratu
re (
K)
AMSR Ts BGC Tsoil Tower Tsoil
Soil temperature comparison at Barrow for 2003 (Fily approach, AMSRE 6.9 GHz, 8-day average)
Daily surface moisture and surface temperature derived from satellite microwave remote sensing are used as the primary controls to Rh. The map shows maximum surface moisture during 2002–04 for the pan-Arctic domain, as derived from AMSR-E L3 daily C- and X-band data.
AMSR-E Maximum Soil Moisture during 2002-04
-4
-3
-2
-1
0
1
2
3
1/1 2/10 3/21 4/30 6/9 7/19 8/28 10/7 11/16 12/26
Date
g C
m-2
d-1
Carbon Model with AMSR and MODIS BGC Tower
+Source
-Sink
Comparative carbon source/sink among the model estimated using MODIS and AMSR-E data, Northern Black Spruce Ameriflux tower site-observed data and BIOME-BGC model calculated using local meteorology data for 2003.
SSM/I Spring Thaw Timing vs Net CO2 Exchange
(Alaska-Yukon; 1988-2000)
R2 = 0.585; P < 0.002-30
-20
-10
0
10
20
30
40
-20 -10 0 10 20
Spring thaw anomaly (days)
NE
P a
no
ma
ly (
g C
m-2 y
r-1)
Net CO2 exchange (Biome-BGC)
Higher NEE (+)
Lower NEE (-)
SSM/I-derived timing of spring thaw and annual C cycle anomalies (1988–2001) depicted by the regional ecosystem process model (Biome-BGC) simulations of NEE for Alaska.
The microwave derived surface temperature and soil moisture used to estimate NEE at the boreal-Arctic region and validated using flux tower sites and RIIMS 25km meteorology. The map shows pan-Arctic daily NEE on June 26, 2003.
Biome-BGC Model Derived Daily NEE June 26, 2003
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