AMWG Variability Diagnostics for Daily Data

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Intraseasonal Variability

Daily 200 hPa velocity potential anomalies computed and then averaged
over 5S-5N, 20-70 day bandpass filter then applied. Hovmöller plots.
Bandpass filter response plot

spcam30_4km_32c. Anomalies are relative to the 1986-2003 mean.

1986-1987
1988-1989
1990-1991
1992-1993
1994-1995
1996-1997
1998-1999
2000-2001
2002-2003

Anomalies computed relative to the time period mean.

NCEP Reanalysis	CAM3 Amip (T85)
1981-1982	1981-1982
1983-1984	1983-1984
1985-1986	1985-1986
1987-1988	1987-1988
1989-1990	1989-1990
1991-1992	1991-1992
1993-1994	1993-1994
1995-1996
1997-1998
1999-2000

Madden-Julian Oscillation

Time series of daily 200 hPa zonal wind averaged over 10N-10S.
200 hPa zonal wind bandpass filtered for 20-100 day period.
MJO Index defined as the running variance of the bandpass filtered data.

spcam30_4km_32c
NCEP Reanalysis
CAM3 Amip (T85)

Histograms

Histograms of daily precipitation rate for the Tropics and NH Extratropics.

spcam30_4km_32c
NCEP Reanalysis
CAM3 Amip (T85)