Climate%20Variability%20and%20%20Potential%20Predictability%20in%20CFS

1
Potential Predictability
ENSO
NEUT
El Nino
Mdl
La Nina
Obs
Variability ENSO Mdl lt Obs NEUT Mdl
gt Obs
Neut
2
Regime dependent bias corrected
Conventional bias corrected
Raw forecast skill
3
Climate Variability and Potential
Predictabilityin CFS

• Wilbur Y. Chen
• Climate Prediction Center
• NCEP/NWS/NOAA

4
MDL
Total Variance
Clim
OBS
Diff
5
More brown than blue
6
DML
ENSO DJFs
NEUT DJFs
OBS
have
have
DIFF
More Positive
More Negative
7
ENSO DJFs
NEUT DJFs
MDL
OBS
Ratio
More gtgt 1.
Less gt 1.
8
MDL VAR of ENS Means
Versus ENS Spreads
A
B
A
B
9
Mdl Behavior clim noise
is smaller when there is ENSO
forcing
Neutral
larger
ENS Spreads
ENS Means
ENSO
smaller
Diff
10
Ens mean
Ens spread
Neut
ENSO
More lt 1.
More gt 1.
Ratio
Mdl VAR Ratio Neutral / ENSO
11
Warm DJFs
smaller
larger
Clim Signal
Clim Noise
Cold DJFs
larger
smaller
DIFF
More Negat
More Posit
12
Potential Predictability
Total
El Nino DJFs
La Nina DJFs
ENSO
VAR of Clim Signal --------------------------
---------- Total VAR (SignalNoise)
Neut
13
El Nino DJFs
La Nina DJFs
14
Potential Predictability
for ENSO DJFs
for Neutral DJFs
15
Potential Pred Warm vs Cold