we carried out the QPF verification of the three model versions (COSMO-I7, COSMO-7, COSMO-EU) with the following specifications:

• From January 2006 till July 2007

• Dataset: high resolution network of rain gauges coming from COSMO dataset and Civil Protection Department about 1300 stations

• Method: 6h or 24h averaged cumulated precipitation value over meteo-hydrological basins

Last results on precipitation verification over Italy(Elena Oberto, Marco Turco - ARPA Piemonte)

• We performed the seasonal trend over the last year (mam’06- mam’07)

• We performed the daily trend

we present COSMO-I7 verification results over a long period (from 2003 till now) over Italy and a comparison between COSMO-I7 and COSMO-I2

COSMO-I7 COSMO-7 COSMO-EU

BIAS D+2 10mm/24h

200601-200707

BIAS D+2 10mm/24h

200601-200707

BIAS D+2 10mm/24h

200601-200707

The BIAS has a quite similar pattern for the three versions for North Italy: in general there is an overestimation over the mountain areas and an underestimation over the lowlands. For central and South Italy COSMO-7 and COSMO-EU are similar: there are more cases of underestimation, while COSMO-I7 presents more cases of overestimation.

(the values in the Abruzzo region maybe are due to observed data problems)

COSMO-I7 COSMO-7 COSMO-EU

POD D+2 10mm/24h

200601-200707

POD D+2 10mm/24h

200601-200707

POD D+2 10mm/24h

200601-200707

The best values are in the North but the three versions have different skill; COSMO-7 has very good values over alpine chain; COSMO-EU has good values in the Northwest. In general, the Eastern side presents the lowest values.(the low POD values in the Abruzzo region maybe are due to observed data problems)

COSMO-I7 COSMO-7 COSMO-EU

FAR D+2 10mm/24h

200601-200707

FAR D+2 10mm/24h

200601-200707

FAR D+2 10mm/24h

200601-200707

The three versions have quite similar pattern skill: the worst values are in the South, central, and mountains areas. Slightly more false alarm for COSMO-I7. (the high FAR values in the Abruzzo region maybe are due to observed data problems)

COSMO-EUCOSMO-7

Seasonal comparison between COSMO-EU/COSMO-7 (D+2)

mam06, jja06, djf7: COSMO-7 better than COSMO-EU;

mam07, better bias for COSMO-EU, better pod COSMO-7

It seems there is a better skill in latest three seasons, less FAR, more POD

COSMO-7COSMO-I7

Seasonal comparison between COSMO-7/COSMO-I7 (D+2)

mam06, son06, djf07, mam07: COSMO-7 better than COSMO-I7

It seems there is a better skill in latest three seasons, less FAR, more POD

COSMO-EUCOSMO-I7

Seasonal comparison between COSMO-EU/COSMO-I7 (D+2)

djf07 and mam07: COSMO-EU better BIAS than COSMO-I7 but worse POD;

jja06, better COSMO-I7 than COSMO-EU

It seems there is a better skill in latest three seasons, less FAR, more POD

COSMO-7

Seasonal comparison: MAM 2007 (for-obs)/obs %

COSMO-I7 COSMO-EU

Balance of negative and positive error distributed all over the territory !

COSMO-7COSMO-I7COSMO-EU

Daily trend from Jan06 to Aug07 General remarks:

•bias>1 (particularly for COSMO-I7)

•It is evident a sort of diurnal cycle

COSMO-7COSMO-I7COSMO-EU

35

Open question: for low thresholds the bias peak occurs during midday, but for high thresholds it is shifted to midnight. Why??

(For high thresholds the events mainly occurred during spring-summer so the precipitation have a great convective component…)

FOCUS ON COSMO-I7: SEASONAL TREND

for the period from 200212 to 200706 (DJF’03- MAM’07)

FOCUS ON COSMO-I7: SEASONAL TREND

for the period from 200212 to 200706 (DJF’03- MAM’07)

In general there is not a remarkable trend. It has been chosen the 20 mm/24h threshold because of a slightly positive trend.

There is a seasonal cycle with generally better skills during autumn and worse skills during summer.

D+2 is worse than D+1

COMPARISON COSMO-I7/COSMO-I2: 200705-200707

BIAS; D+1 (+00/+24H); PERIOD: 200705-200707

BIAS; D+2 (+24/+48H); PERIOD: 200705-200707

+ COSMO-I7

COSMO-I2

+ COSMO-I7

COSMO-I2

Above 10 mm/24 the bias

difference is statistically significant: COSMO-I2

overestimates more then COSMO-I7

COMPARISON COSMO-I7/COSMO-I2: 200705-200707

POD; D+1 (+00/+24H); PERIOD: 200705-200707

POD; D+2 (+24/+48H); PERIOD: 200705-200707

+ COSMO-I7

COSMO-I2

+ COSMO-I7

COSMO-I2

statistically significant

differences for high thresholds with better POD

for COSMO-I2

statistically significant

differences for medium-high

thresholds with better POD for

COSMO-I2

COMPARISON COSMO-I7/COSMO-I2: 200705-200707

FAR; D+1 (+00/+24H); PERIOD: 200705-200707

FAR; D+2 (+24/+48H); PERIOD: 200705-200707

+ COSMO-I7

COSMO-I2

+ COSMO-I7

COSMO-I2

statistically significant

differences for medium

thresholds with greater false

alarm numbers for COSMO-I2

….to sum up

•The error spatial pattern shows a general underestimation on the

plain and overestimation on the mountain.

•The seasonal trend over the last year (mam’06- mam’07) seems to

have a better skill in the latest three seasons..positive trend!

•We performed the diurnal cycle: moving from low to high

precipitation amount the overestimation peak is shifted from midday to

midnight open discussion

•COSMO-I7 verification results over a long period (from 2003 till

now) over Italy do not show a worsening but the improvement is only

relative to high thresholds.

•The comparison between COSMO-I7 and COSMO-I2 during last

three months generally shows a better scores for COSMO-I7