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National Meteorological AgencyNational Meteorological Agency

Feb, 2013

Climate Assessment forBega 2012/13

in Ethiopia

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OUTLINE

IntroductionForecast based on global and

regional VS ObservedsituationSeasonal Rainfallperformance Heavy fallsSeasonal temperature

performance

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Introduction to Bega season:Introduction to Bega season: Bega is the second rainy season for south and

southeastern Ethiopia.

October rain has the highest share of Bega,particularly, over south and southeasternregions.

After October, much of northern half of thecountry remain under dry weather. Hence, rainthat falls after this month is considered as

UNSEASONAL RAIN

Frost occurs during the season, mainly overnortheastern central, eastern and southern

highlands

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Real-time observation Near-neutral ENSO prevailed in

September 2012

Projected ENSO:

More than half of the ENSO predictionmodels predict Weak El nio andpositive IOD conditions developingaround the September January season

No models indicate a re-emergence of LaNina conditions

ENSO Forecast:ENSO Forecast:

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Selection of analogue years

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Observed Conditions

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The Observed global and regional situation

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** Poor resemblance between analogue years

and current conditions

**** ENSO-neutral signal has persisted

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Seasonal Rainfall performance

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OCTOBER 2012 RAINFALLAMOUNT IN MM

PERCENT OF NORMAL RAINFALL for October 2012

BN N AN

2 9

12

0

1 0

2 13 2

5 37

6 0

1 3 0

8 0

1 4

6 6

4 2

2 7 0

0

0

6

0

0

4 1

1 1 7

5 2

1

2 6

0

1 2 2

2 4

1

0

1 5 7

5 3

2 5

0

0

5

2 4

3

1 1 3

6

2

3 3

1 5 5

6 1

4 4

1 3 8

1 8 9

5

1

0

9

3 4

1 0 5

6 4

2 6 7

3 2

1 2 6

4

1

2 6

3 30

6 4

1

2 2

6

0

5 0

9 4

2 0

1 4

1

5 3

1 2 8

8 5

7

6 7

1

8 2

1 1

0

3 8

1 4

0

2 9

2

2

0

0

5 1

1 4 0

9 3

1 8

2 0 4

5

1 9 2

6 9

5

2 5

5 0

1 0 0

1 5 0

2 0 0

2 5 0

3 0 0

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NOVEMBER 2012 RAINFALLAMOUNT IN MM PERCENT OF NORMAL RAINFALL for November

2012

BN N AN

2

01

0

7

3 04 4

3 0

1

0

1 1 8

7 9

5 8

1 9

1 1 4

1 4

7 6 0

0

0

2

0

0

6 5

7 7

4 2

0

0

4 0

0

0

1 5 5

1 0 8

5 1

0

5 1

0

1 3 7

5

4 8

6 6

5 1

1 4 9

2 4

0

7 8

1 3 9 7 6

3 9

6 1

4

1 1

6 3

5 4

4 3

0

0

1 0

0

1 6

1 0 5

0 0

1 9

1

6 0

2 5

6 1

0

7

0

1 0 0

1 0

2 8

0

1 6

1 3

0

0

2

3

0

2 2

0

7 3

1 0 3

2 6

1 7

3

1 5 2

1

5 60

4 0

5

2 5

5 0

1 0 0

1 5 0

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DECEMBER 2012 RAINFALLAMOUNT IN MM PERCENT OF NORMAL RAINFALL for December

2012

BN N AN

5

2 21 0

5

1

6

00

0

0

1 8

2 4

3 4

6

1 4

5

8

1 1

00

1 8

1 1

1

0

3

0

6

2 8

6 2

0

0

0

4

1

0

1 6

1 5

2

2 0

0

0

1 2

9

5

0

3

4 6

1 0

1 1

4 9

1 9

0

7

0

6 7

6 2 5

2 1

5 5

1 3

7

1 5

1 31

1 1

3

0

0

0

1

2 0

3 6

2 0

1

4

0

5

1 6

0

1 2

4

3 9

8

0

0

4

0

2

0

1

6

0

0

2

0

7 1

7

0

0

9 8

0

2 31 0

4 6

2 1

5

2 5

5 0

7 5

1 0 0

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JANUARY2013 RAINFALL AMOUNT IN MMPERCENT OF NORMAL RAINFALL FOR January

2013

BN N AN

2 2

04

1

0

4 1

1 10

31

2 4

7

0

2 3

0

1 4

1

0

2 2

0

3 1

0

1 8

4 5

2

5 8

3 6

0

1

7

1

8

3 2

1

0

0

2 3

0

0

1

0

4 0

0

4

0

0

1 4

1 5

1 0

1

3 3

3 5

1 1 2 1

4 6

1 7

81 4

10

1 1

1 5

0

0

5 7

9

3

1 9

2 1 0

3 2

4

0

2

1 2

1 8

1 2

4

2 8

8

0

3

0

5 5

0

2

2

0

1

0

7 3

1 1

0

0

5 6

1 4

1 70

2 5

1 2

5

2 5

5 0

7 5

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SEASONAL RAINFALL AMOUNT IN MM FOR Bega2012/13

PERCENT OF NORMAL RAINFALL FOR

Bega 2012/13

BN N AN

5 7

2 41 7

6

6 4

6 27 7

8 62 6

2 2 6

2 4 9

1 4 4

7 1

1 8 4

7 7

1 1 4

0

4 0

1 9

3 2

2 1

1 5 7

2 2 4

2 1 5

3 7

2 6

1

1 2 2

7 5

3

8

3 5 9

1 7 6

7 9

5

1 1 8

1 6

2 5 9

5 8

2

8 4

2 7 1

9 1

1 0 6

3 4 9

2 8 5

1 6

1 2

4 3

2 1 3

3 3 6 3 9 9

1 3 8

2 5 8

2 9

1 8

1 1 8

1 0 21

1 2 8

5

2 2

7 3

1 0

8 8

2 5 5

2 5 0

6 6

1 0

1 1 3

1 6 0

1 7 4

2 5

9 9

9

2 7 0

3 6

0

6 0

1 3

7 1

0

3 4

1 3

2

2 7

9

3

1 2 4

3 8 7

1 3 7

1 7

2 0

5 0 9

2 0

2 8 71 0

1 8 0

1 0 1

2 5

5 0

1 5 0

2 5 0

3 5 0

4 5 0

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Anomalous wet conditions Spatial rf distn (%) in the dekad

1st dekad,

December2nd dekad,

December3rd dekad,

November

2nd dekad,

November

1st dekad,

January

2nd dekad,

January

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SUMMARY Southern half of Ethiopia, where Bega is the second rainy

season, received normal to above normal rains. The wet

condition was forecasted in advance. October and November rainfall amount and distribution were

concentrated over much of the nation. Both seasonal and unseasonal rains were enhanced over

southern and western half of the country. As a result, rainfall

recorded in the month of November exceeded the normalvalues.

Month of November was the wettest month. During November and December moths unseasonal rains were

observed over much of Amhara and some parts of Oromia andTigray.

During the season, , rainfall amounts was normal to above normalover southern half, western and northwestern parts of the nation.

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RAINFALL AMOUNT RECORDED

IN 24 HOURS THAT

EXCEEDING 30MM

Heavy fallsHeavy falls

i f O 2012

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Heavy Falls in the month of October 2012

Region No.ofstationswith Heavy

falls

Highest Heavy fall and

Station

Highest No. of

days with Heavy

falls and Station

Amhara

Oromiya

6

53.5mm/ H/mariam 2d/ H/mariam

SNNPR

4

76.0mm/ Burji 3d/ Burji

B/ Gumuz 57.4mm /Pawe

2d

2d/

Somali1

337.0mm/ Dangela

1d/ Dangela

Gambela 1

2

Max. 102.5 mm/ Max. 3d/ Burji

60.7mm/Gambela

Tot. =17

102.5102.5MM/Dega Habour

1d/

H F ll i h h f N b 2012

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Heavy Falls in the month of November 2012

Region No. of Stations

with Heavy falls

Highest Heavy fall and

Station

Highest No. of days

with Heavy falls and

Station

Tigray 1 46.6mm/ Shire 1d/shire

Amhara 4 56.0mm/ Aykel 1d/

Oromiya 7 77.1mm/ D/mena 2d/nejo

SNNPR 4 79.0mm/ Tepi 1d/

B/ Gumuz 1 39.1mm/ Chagni 1d/

Max. 79.0mm/ Tepi Max. 2d/ nejo

2 61.5mm/Lare2d/Gambela

Gambela

Tot. 19 stations

H F ll i th th f D b 2012

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Heavy Falls in the month of December2012

Region No. of Stations withHeavy falls

Highest Heavy falland Station

Highest No. of dayswith Heavy fallsand Station

Oromiya 3 34.7mm/ Gololcha 1d/

SNNPR 1 32.1mm/ Tepi 1d/

Tot. 4 Max. 1dMax. 34.7/ Gololcha

H F ll i th th f J 2013

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Heavy Falls in the month of January 2013

Region No. of Stations

with Heavy

falls

Highest Heavy fall

and Station

Highest No. of days

with Heavy falls and

Station

Amhara 1 43.5mm/ Sirinka 1d/

1 31.6mm/

Methehara

1d/

1 39.0mm/ Maji 1d/

1 30.1mm/ Jijiga 1d/

Tot. 4 Max. 43.5mm/ Sirinka Max. 1d/

Oromiya

SNNPR

Somali

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Seasonal temperaturePattern

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SUMMARY

In January, the lowest minimum temperatureof -3.5C recorded at Debre Berhan

Otherwise, no significant drop in night time

minimum temperatures over the country.

No significant frost events were observedover Ethiopia, including over the frost pornareas of the country.

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Seasonal climate

Forecast Verification

P t f N l R i f ll f BBega 2012/13Climate Outlook Tercile Rainfall

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Percent of Normal Rainfall for Bega

2012/13

BN N AN

3535

4545

2020

2020

5555

2525 3535

4545

2020

3535

5050

1515

g

Probability

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CONCLUSION

The Bega 2012/13 were remained under near-neutral ENSO condition.Near neutral condition contributed for at least theoccurrence of normal climate across the northern

half of Ethiopia, where bega is dry season.

The seasonal rainfall performance inclined towetter than the normal over the southern half of thecountry.

The overall rainfall conditions that prevailed overthe country were well predicted, while slightly over-

forested over the northeast regions

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Thank You