A comparison of ECMWF fields to GFS fields

September 2003

500 hPa height

Zonal means

Analyses

RMS and SD Differences

Analyses

1 day forecasts

2 day forecasts

3 day forecasts

5 day forecasts

RMS Z500

Analyses

1 day forecasts

2 day forecasts

3 day forecasts

5 day forecasts

Error

Time-mean	1 day forecasts	2 day forecasts	3 day forecasts	5 day forecasts
RMS	1 day forecasts	2 day forecasts	3 day forecasts	5 day forecasts
SD	1 day forecasts	2 day forecasts	3 day forecasts	5 day forecasts

Regional

Monthly means

EC analyses

GFS analyses

Zonally asymmetric monthly means

EC	Analyses	1 day forecasts	2 day forecasts	3 day forecasts	5 day forecasts
GFS	Analyses	1 day forecasts	2 day forecasts	3 day forecasts	5 day forecasts

Differences EC-GFS

Time -mean	Analyses	1 day forecasts	2 day forecasts	3 day forecasts	5 day forecasts
RMS	Analyses	1 day forecasts	2 day forecasts	3 day forecasts	5 day forecasts
Normalized RMS	Analyses	1 day forecasts	2 day forecasts	3 day forecasts	5 day forecasts
Stan dev.	Analyses	1 day forecasts	2 day forecasts	3 day forecasts	5 day forecasts

Time-mean error in 500 hPa heights

EC	1 day	2 day	3 day	5 day
GFS	1 day	2 day	3 day	5 day

Difference in systematic error in 500 hPa heights EC-GFS

1 day

2 day

3 day

5 day

Rms 500 hPa heights

EC	Analyses	1 day	2 day	3 day	5 day
GFS	Analyses	1 day	2 day	3 day	5 day

Error in rms 500 hPa heights

EC	1 day	2 day	3 day	5 day
GFS	1 day	2 day	3 day	5 day

Difference in error in rms 500 hPa heights EC minus GFS

1 day

2 day

3 day

5 day

Difference in rms 500 hPa height EC-GFS

Analyses

1 day forecasts

2 day forecasts

3 day forecasts

5 day forecasts

RMS error in 500 hPa height

EC	1 day	2 day	3 day	5 day
GFS	1 day	2 day	3 day	5 day
EC-GFS	1 day	2 day	3 day	5 day

Stan. Dev. Error in 500 hPa height

EC	1 day	2 day	3 day	5 day
GFS	1 day	2 day	3 day	5 day
EC-GFS	1 day	2 day	3 day	5 day

Correlation of 500 hPa height in EC and GFS

Analyses

1 day forecasts

2 day forecasts

3 day forecasts

5 day forecasts

850 hPa Temperature Analyses

Zonal mean

Zonal mean RMS

Time-mean	EC	GFS	EC-GFS
Zonally asymmetric	EC	GFS
RMS	EC	GFS	EC-GFS

RMS difference

Normalized RMS difference

EC-GFS correlation

Wind Analyses

Zonal means

Zonal wind	850	200
Meridional wind	850	200
Transient eddy kinetic energy	850	200
Horizontal divergence	850	200

Zonal wind

850 eastern hemisphere	EC	GFS	EC-GFS
850 western hemisphere	EC	GFS	EC-GFS
200 eastern hemisphere	EC	GFS	EC-GFS
200 western hemisphere	EC	GFS	EC-GFS

Meridional wind

850 eastern hemisphere	EC	GFS	EC-GFS
850 western hemisphere	EC	GFS	EC-GFS
200 eastern hemisphere	EC	GFS	EC-GFS
200 western hemisphere	EC	GFS	EC-GFS

RMS Difference

850 hPa Zonal wind	Eastern hemisphere	Western hemisphere
850 hPa Meridional wind	Eastern hemisphere	Western hemisphere
200 hPa Zonal wind	Eastern hemisphere	Western hemisphere
200 hPa Meridional wind	Eastern hemisphere	Western hemisphere

Normalized RMS Difference

850 hPa Zonal wind	Eastern hemisphere	Western hemisphere
850 hPa Meridional wind	Eastern hemisphere	Western hemisphere
200 hPa Zonal wind	Eastern hemisphere	Western hemisphere
200 hPa Meridional wind	Eastern hemisphere	Western hemisphere

Correlation

850 hPa Zonal wind	Correlation eastern hemisphere	Correlation western hemisphere
850 hPa Meridional wind	Correlation eastern hemisphere	Correlation western hemisphere
200 hPa Zonal wind	Correlation eastern hemisphere	Correlation western hemisphere
200 hPa Meridional wind	Correlation eastern hemisphere	Correlation western hemisphere

Streamfunction

850 eastern hemisphere	EC	GFS	EC-GFS
850 western hemisphere	EC	GFS	EC-GFS
200 eastern hemisphere	EC	GFS	EC-GFS
200 western hemisphere	EC	GFS	EC-GFS

Transient eddy kinetic energy

850 eastern hemisphere	EC	GFS	EC-GFS
850 western hemisphere	EC	GFS	EC-GFS
200 eastern hemisphere	EC	GFS	EC-GFS
200 western hemisphere	EC	GFS	EC-GFS

Relative vorticity

850 eastern hemisphere	EC	GFS	EC-GFS
850 western hemisphere	EC	GFS	EC-GFS
200 eastern hemisphere	EC	GFS	EC-GFS
200 western hemisphere	EC	GFS	EC-GFS

Horizonal Divergence

850 eastern hemisphere	EC	GFS	EC-GFS
850 western hemisphere	EC	GFS	EC-GFS
200 eastern hemisphere	EC	GFS	EC-GFS
200 western hemisphere	EC	GFS	EC-GFS