Verification

Precipitation verification (overestimation):a common view

of the behaviour of the LM, aLMo and LAMI

Francis Schubiger and Pirmin Kaufmann, MeteoSwissUli Damrath, DWD

Elena Oberto, Marco Turco, Paolo Bertolotto, ARPA Piedmont

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 2

Verificationdifference of mean monthly rain gauges in D and CH

C. Schraff, DWD

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 3

VerificationVerification of aLMo Winter 03/04 over Switzerland

full line: obs (ANETZ); dashed: black: aLMo, red: LM

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 4

VerificationVerification of aLMo Winter 02/03 over Switzerland

full line: obs (ANETZ); dashed: black: aLMo, red: LM

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 5

VerificationVerification of the cloud ice testsuite in aLMofrom 04.02-19.03.2004

full line: obs (ANETZ); dashed: black: aLMo

blue: aLMo-cloud ice, red: LM

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 6

VerificationVerification of aLMo Winter 04/05 over Switzerland

full line: obs (ANETZ); dashed: black: aLMo, red: LM

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 7

Verification

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 8

VerificationVerification with raingauges in D and CH

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 9

VerificationVerification with raingauges in CH

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 10

VerificationVerification of aLMo Winter 04/05 SYNOP

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 11

VerificationPrecipitation: scores of aLMo Winter 00/01

verification with 12h-sums from SYNOP

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 12

VerificationPrecipitation: scores of aLMo Winter 01/02

verification with 12h-sums from SYNOP

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 13

VerificationPrecipitation: scores of aLMo Winter 02/03

verification with 12h-sums from SYNOP

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 14

VerificationPrecipitation: scores of aLMo Winter 03/04

verification with 12h-sums from SYNOP

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 15

VerificationPrecipitation: scores of aLMo Winter 04/05

verification with 12h-sums from SYNOP

VerificationLatest results in the precipitation verification over Piedmont

Elena Oberto, Marco Turco, Paolo Bertolotto(*) ARPA Piemonte, Torino, Italy

• Eyeball verification: seasonal cum maps of D+1 forecast

• Seasonal statistical indices

• Special focus over last winter (DJF’05): Statistical indices for increasing thresholds

Scatter plot of daily precipitation over each basins: seasonal and monthly

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 17

Verification

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 18

Verification

Prec (mm)

ALMO

LAMI

LOKAL

DJF 2004

OBSERVED

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 20

Verification

Scale (mm)

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 21

VerificationOBSERVED

Prec (mm)

aLMo 00

LM-DWD 00

LAMI 00

Verification over Piedmont ; winter 04/05

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 22

VerificationSeasonal trend of BIAS and ETS Threshold=10mm/24h Forecast time: +00/+24.

The error bars indicates 2.5th and 97.5th percentiles of resampled distribution, applied to the "reference" model.Djf’05 too much dryno statistic

in the next slides there is a special focus

LoKalaLMoLAMI

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 23

VerificationSeasonal trend of BIAS and ETS Threshold=10mm/24h Forecast time: +24/+48.

The error bars indicates 2.5th and 97.5th percentiles of resampled distribution, applied to the "reference" model.

aLMo

LAMI

LoKal

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 24

VerificationConclusions

a possible cause for the precipitation overestimation is the cloud ice scheme

but another causes (masked by the precipitation variability) are also possible, because

already before the introduction of cloud ice scheme we had seasons with precipitation overestimationwe have regions (especially in southern Europe) with no changes in the yearly (seasonal) biases in the last years

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 25

VerificationOutlook (1)

more work necessary to fix the causes for precipitation overestimation

scatter plots of daily precipitation sums 'LM vs raingauges, SYNOP-stations, RADAR areal mean’ : this helps to see if this overestimation is due to (some few) cases where the model gives (much) precipitation that is not observed, or whether overestimation of precipitation is a problem in all cases

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 26

Verification

winter 2004(djf)

aLMo D+1

Scatterplot of mean daily precipitation over the Piedmont basins

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 27

Verification

winter 2004

(djf)

Lokal D+1

Scatterplot of mean daily precipitation over the Piedmont basins

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 28

Verification

winter 2004

(djf)

LAMI D+1

Scatterplot of mean daily precipitation over the Piedmont basins

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 29

Verification

winter 2005(djf)

aLMo D+1

Scatterplot of mean daily precipitation over the Piedmont basins

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 30

Verification

winter 2005

(djf)

Lokal D+1

Scatterplot of mean daily precipitation over the Piedmont basins

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 31

Verification

winter 2005

(djf)

LAMI D+1

Scatterplot of mean daily precipitation over the Piedmont basins

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 32

Verificationscatterplot daily precipitation Germany: August 2002

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 33

VerificationScatterplot daily precipitation Germany: December 2002

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 34

VerificationScatterplot daily precipitation Germany: December 2004

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 35

VerificationOutlook (2)

more work would be necessary to fix the causes for precipitation overestimation

scatter plots of daily precipitation sums 'LM vs raingauges, SYNOP-stations, RADAR areal mean’ : this helps to see if this overestimation is due to (some few) cases where the model gives (much) precipitation that is not observed, or whether overestimation of precipitation is a problem in all cases

set up a simple conditional verification by discriminating:

between events of different (observed) vertical stability i.e., unstable = convective (?), stable = stratiform (?)convective/stratiform precip in the model. This would help to attribute the problem to the grid-scale precipitation scheme or the convection scheme, or something else.

franci

s.sc

hubig

er@

Mete

osw

iss.

chC

OSM

O G

enera

l M

eeti

ng,

Zuri

ch,

20

-23

.09

.05 36

VerificationOutlook (3)

strong link to WG1-WG3 for sensitivity studies on a set of selected cases / episodes:

analysis / data assimilation

dynamics and numerics

physics