simulated and observed pre-industrial to modern vegetation and climate changes
DESCRIPTION
Simulated and Observed Pre-Industrial to Modern Vegetation and Climate Changes. OCT 2004. Michael Notaro U.W. Madison Center for Climatic Research [email protected]. OBJECTIVES. - Study the impact of rising levels of equivalent carbon dioxide on global vegetation and climate. - PowerPoint PPT PresentationTRANSCRIPT
- Later continue study to predict future changes in vegetation and climate
- Study the impact of rising levels of equivalent carbon dioxide on global vegetation and climate
- Evaluate FOAM-LPJ model
- Focus on higher latitudes
- Compare findings with satellite data and tree ring data
DATASETSDATASETS- Global Potential Vegetation (Ramankutty and Foley, 1999) - Global Continuous Fields of Vegetation Cover for 1992-1993 (DeFries et al., 1999; 2000) - Pathfinder V3 AVHRR FPAR (1981-2001) (Myneni et al., 1997)- HYDE Global Historical Land Cover for 1900 and 1990 (Goldewijk, 2001; Goldewijk and Battjes, 1997)- International Tree-Ring Data Bank’s Tree Ring Width (212 sites) (1800-1999) (45ºN-75ºN) (<500m) (standardized)- NCEP-NCAR Reanalysis (Kalnay et al., 1996)- NASA GISS Land-Ocean Surface Air Temperature Anomalies (1900- 1999) (Hansen et al., 1999; Reynolds and Smith, 1994; Smith et al.,1996)- Climatic Research Unit’s CRUTEM2 Monthly Land Air Temperature Anomalies (1851-2003) (Jones and Moberg, 2003)- NOAA Extended Reconstruction SST (ERSST) (1900-1999) (Smith and Reynolds, 2003)- Xie-Arkin CPC Merged Analysis of Precipitation (1979-2001) (Xie and Arkin, 1996; 1997) - CRU TS2.0 Land Surface Precipitation (1901-2000)- Willmott-Matsuura V1.01 Temperature and Precipitation (1950-1996) (Willmott and Matsuura, 2000)
Fraction of Photosynthetically Active Radiation
MEAN
TREND
April-October 1982-2000 FPAR Anomalies
FOAM = Fast Ocean Atmosphere Model (Jacob, 1997) - R15 (PCCM3+OM3)
LPJ = Lund-Potsdam-Jena dynamic vegetation model (Sitch, 2000) - 1.4°x2.8°
FOAM-LPJ = fully coupled global atmosphere-ocean-land model with
dynamic vegetation
Percent difference (Model-Obs) in Annual Average Land Precipitation (Obs = Xie Arkin 1979-2001)
Contours: 20, 50, 100, and 300%
W
W
WW
W
D
D
January and July FPARJAN JUL
OBS
MODEL
Model Obs
1900 1990
FC Diff
Comparison of Simulated and Satellite-Based % Tree Cover
1950-1996 Surface Air T Change (Willmott-Matsuura)
ANNUAL
DJF
Change in Simulated Surface Air T
Shading: <0.10
Change in Simulated Surface Air T (DJF)
Shading: <0.10
Trend in Simulated PrecipitationRP
P
R
GlobalAnnual T
DJF T (Land
38-60N, 120W-140E
Global Annual
SST
GlobalTree
Cover
40-75N Boreal
SummergTree Cover
MJJASFPAR
TREE COVER VEGETATION COVER
R (0.7%)
P (1.9%)
RP (2.3%)
R (1.0%)
P (1.7%)
RP (2.9%)
TrendIn %
ForestCover
RP
R
P
Change in FPAR
RP
AVHRR
R
P
AVHRRRemote
Percent Change in Evapotranspiration (Run P)
€
FPAR = f i di + f i ′ d i
i=1
9
∑ + ′ f i
i=1
9
∑i=1
9
∑ di + ′ f i
i=1
9
∑ ′ d i
Decomposition of Simulated FPAR
For the 9 pft’s,
f = vegetation cover fraction
d = seasonal leaf cover fraction
Mean FPARwith no trend
Change in leaf cover or lengthof growing season(GDD)
Change infractionalvegetationcover
Interactionsor feedbacksbetween f and d (small)
€
f ′ d
€
′ f d
€
′ f ′ d
Trend
€
f ′ d
€
′ f d
€
′ f ′ d
Trend
€
f ′ d
€
′ f d
€
′ f ′ d
Trend
DECIDUOUS EVERGREEN
TreeRing
Width
Apr-Oct T
Ring Width
RP
P R
CONCLUSIONS
- Both satellite data and FOAM-LPJ reveal a global greening trend and poleward expansion of the northern boreal forest
- The radiative forcing is responsible for most of the warming trend, although the physiological forcing contributes some additional local warming.
- While the physiological forcing dominates the global greening trend, both forcings play a role in the boreal expansion.
- FOAM-LPJ captures the major global biomes but overproduces tree cover due to FOAM’s wet bias and LPJ’s woody bias.