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Preliminary evaluation of Rossby wave in T511 Nature run. July 12 2007 Nikki Priv é. Standard deviation of 200 mb anomaly v (meridional wind). Nature Run (top) vs reanalysis (center ECMWF and bottom NCEP). 13-month NR, 12 years of reanalysis data (1989 – 2002). - PowerPoint PPT Presentation
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Preliminary evaluation of Rossby wave in T511 Nature run
July 12 2007Nikki Privé
Standard deviation of 200 mb anomaly v (meridional wind).
Nature Run (top) vs reanalysis (center ECMWF and bottom NCEP). 13-month NR, 12 years of reanalysis data (1989 – 2002).
NR shows similar pattern, but stronger amplitude, esp. in Southern Hemisphere midlatitudes – due to higher spatial and temporal resolution?
StdDev v', DJF StdDev v', JJA
NH (30N-60N) 'ensemble' comparison of 200 mb v' standard deviation
blue = ECMWF
red = NCEP
black = Nature Run
blue = ECMWF
red = NCEP
black = Nature Run
SH (30S-60S) 'ensemble' comparison of 200 mb v' standard deviation
Comparison of zonal mean zonal wind jet maxima, NR and ECMWF only, Northern Hemisphere
blue – ECMWF
green star – Nature Run
blue – ECMWF
green star – Nature Run
Comparison of zonal mean zonal wind jet maxima, NR and ECMWF only, Southern Hemisphere
Amplitude of rossby wave envelopes found via Zimin (2003) using 200 mb v-anomaly field. This panel shows the mean wave envelope amplitude (m/s) for the Nature Run (top), ECMWF reanalysis (center), and NCEP reanalysis (bottom). Patterns similar to that seen in standard deviation of v'.
Wave envelope magnitude, DJF Wave envelope magnitude, JJA
Northern Hemisphere, power spectra decomposition of wave envelope field.
Southern Hemisphere, power spectra decomposition of wave envelope field.
Dominant wavenumber and group velocities of the 200 mb v' field found using power spectra decomposition (a la Hayashi 1971). The wave of greatest power on each latitude band is identified.
Westward propagating waves dominant in the deep tropics, eastward propagating waves dominant in midlatitudes. Diagnostics in agreement with studies using different method (eg. lag-correlation, Chang (1999)).
Dominant waves, DJF Dominant waves, JJA
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