A Comparison of FNOC and the MRF in the Tropics

 

Glenn.White@noaa.gov

 

               During the last few years the NCEP global model has trailed other centers in standardized skill scores in the tropics, particularly in root mean square wind vector error at 850 hPa.  During this hurricane season (2001) the NCEP global model outperformed other centers in forecasting the tracks of hurricanes, but still trailed them in RMS vector error.  This page presents some preliminary results of an intercomparison of tropical analyses and 3-day forecasts by the NCEP global medium-range forecast (MRF) model and the U.S. Navy global model (FNOC). 

 

Root-mean-square error 20S-20N

 

Zonal wind

 

850 hPa

300 hPa

200 hPa

Time series of rms errors and rms differences in analyses and forecasts

Time series of rms errors and rms differences in analyses and forecasts

Time series of rms errors and rms differences in analyses and forecasts

 

Vertical cross-sections

 

Zonal Wind

Meridional Wind

RMS error FNOC

RMS error FNOC

RMS error NCEP

RMS error NCEP

Difference in RMS error FNOC-NCEP

Difference in RMS error FNOC-NCEP

RMS difference in analyses

 

RMS difference in forecasts

 

 

Root-mean-square value of zonal wind

 

850 mb

300 mb

200 mb

Analyses and 3 day fcsts time series

Analyses and 3 day fcsts time series

Analyses and 3 day fcsts time series

 

Vertical cross-sections

 

FNOC

NCEP

FNOC-NCEP

Analyses

Analyses

Analyses

3 day fcsts

 

3 day fcsts

3 dy fcsts-analyses

3 dy fcsts-analyses

 

 

Time-means

 

Zonal Wind

 

Zonal mean

Equator

Analyses

Analyses

3 day forecasts

3 day forecasts

Differences in analyses, 3 dy fcsts

Differences in analyses, 3 dy fcsts

3 day fcsts minus analyses

3 day fcsts minus analyses

 

Meridional Wind

 

Zonal mean

Equator

Analyses

Analyses

3 day forecasts

3 day forecasts

Differences in analyses, 3 dy fcsts

Differences in analyses, 3 dy fcsts

3 day fcsts minus analyses

3 day fcsts minus analyses

 

Transient Eddies

 

20S-20N

 

Zonal wind

Meridional wind

 

Zonal Mean

 

Zonal Wind

 

FNOC

NCEP

FNOC-NCEP

Analyses

Analyses

Analyses

3 day forecasts

3 day forecasts

3 day forecasts

3 day fcsts minus analyses

3 day fcsts minus analyses

 

 

Meridional Wind

 

FNOC

NCEP

FNOC-NCEP

Analyses

Analyses

Analyses

3 day forecasts

3 day forecasts

3 day forecasts

3 day fcsts minus analyses

3 day fcsts minus analyses