LBA-MIP: Motivation and Overview
Ian Baker, Colorado State University
Movers and Shakers: Gustavo Concalves, Scott Saleska, Natalia
Restrepo, Reto Stockli, Brad Richardson, Ben Poulter, and many
others...(Tower PIs: Don’t forget tower PIs!)
Motivation
•Amazonia: 10% of global biomass
•Gross Carbon fluxes large: net flux uncertain
•Interannual variability?•Several studies: sink during La Nina, source during El Nino (precipitation)
More Motivation
Month
NEE
(flux
to a
tmos
pher
e) kg
C/ha
/mon
th-1
000
-500
050
0
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Model output is mean of 4 gridpoints: -54.5 > longitude > -55.5, -2.5 > latitude > -3.5, for neutral years 1980-81,1984-85,1990, & 1993-95.Data is from Tapajos, km67 site (2.85 S, 55 W, from 10-Apr-01 to 08-May-02) & km83 site (3.05 S, 55 W, from 1-Jul-00 to 1-Jul-01).
0
20
40
60
prec
ip (c
m p
er m
onth
)
TEM / neutral yrsIBIS \ (1980-95)Data (7/00-7/02)
neutral yrs, 1980-95Site (7/00-7/02)
Saleska et al, 2003; Science
Mechanisms: Tapajos km83
•Root Water Access•Hydraulic Redistribution•Deep Soil/Root Access/Respiration Wetness•Combination! Baker et al, 2008 , JGR, in press
Location of Sites
Precipitation Distribution
•Precipitation mean for 3 or 4 years
•Dry season defined as number of months with precipitation < 100mm
•0-1 month dry season at Manaus km34
•7-8 month dry season at Pe de Gigante
Models•SSiB2c1•SSiB2c2•SSiB2c3•SiB3•BiomeBGC•LPJ•HYLAND•JULES•SPASTD•SPAMOD
•SPAPHEN•CLM35c•CLM35nc•SiBCASA•ORCHIDEE•VISITC1•VISITC2•VISITC3•COLM•IBIS
•5PM•SiB2•CLM3DP•CLM300TB•NOAHDV•NOAHSTD•SiB2B•LPJ2•LM3V•CLM3GW
Results!
•Preliminary-most models are being re-run
•netCDF!
•Units
•Sign Convention
•Energy/Water Balance
Site Obs: PDG
Site Obs: K83
Site Obs: K77
Site Obs: K34
Things to Emphasize
•Observation/Model Synthesis
•Seasonal Stress?
•Soil/Rooting depth
•Equifinality of Mechanisms?
Mechanism Equifinality (km83)
What Would We Like to Accomplish?
•Start: Annual cycle
•Next: IAV (don’t forget diurnal cycle!)
•Behavior Across Vegetation/Moisture Gradients
•Amazonia/Continental scale biophysics
•NEE Mechanism Dependence (ENSO)
