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SREDNJA POLJOPRIVREDNA ŠKOLA – BAR NAUTIČKI TEHNIČAR

STRUČNI RAD METEOROLOGIJA

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Kandidat Kićović Danilo ________________

Mentor Pekić Ljubo _______________

Meteorologija

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1.UVOD Ako na brodu I u meteorološkoj službi ne postoji instrument za mjerenje brzine vjetra , procjenjuju se jačina vjetra po Boforovoj ljestvici . Prvu ljestvicu s podjelom od 0 do 12 stepena za procjenu jačine vjetra predložio je 1808 god. Englenski admiral Francis Beaufort koji je jačinu vjetra odredjivao prema djelovanju vjetra na jedra svog broda i drugih brodova na jedra . Otada pa do danas izmjenjene su četri ljestvice , ali je zadržana Boforova ljestvica vjetra i svakom je stepenu odredjena odgovarajuća vrijednost brzine ( čv , odnosno m/s ) i specifičan pritisak vjetra na brod . Ljestvica koja se danas upotrebljava za mjerenje visine od 10m , prihvaćena je na Medjunarodnom meteorološkom kongresu 1946 g. U Parizu . Raspon poslednjih tri ljestvice ( 0-12 ) nije zadovoljio , pa je četvrta Boforova ljestvica proširena do 17 stepeni . Medjutim , u pomorstvu se Boforova ljestvica upotrebljava samo do 12 stepeni . Glavni nedostatak Boforove ljestvice je u tome što stepeni ljestvice , odnosno izgled mora za pojedine stepene , vrijedi isključivo za okean ( otvoreneo more ) a ne za geografska područija , i zato što procjena zavisi od kritike potrioca . Za neka mora postoje posebne ljestvice .

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Meteorologija

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2. BOFOROVA SKALA Wind WMO* Beaufor Wave Speed Wind t Wind Heigh (Knots Classificatio Force t (ft) ) n

Sea Conditions

0

Less than 1

Calm

Sea surface is smooth and mirror-like.

1

1-3

Light Air

Scaly ripples without foam crests.

2

4-6

Light Breeze

Small wavelets with glassy appearing crests and no breaking.

3

7-10

Gentle Breeze

Large wavelets, crests begin to break and whitecaps are scattered whitecaps.

4

11-16

Moderate Breeze

5

17-21

Fresh Breeze 4-8

Moderate waves take longer form and there are many whitecaps and some spray.

6

22-27

Strong Breeze

8-13

Larger waves form and whitecaps are common, along with more spray.

7

28-33

Near Gale

13-20

The sea heaps up and white foam streaks off breakers.

8

34-40

Gale

13-20

Moderately high waves of greater length are formed. The edges of crests begin to break into spindrift and foam blown in streaks.

9

41-47

Strong Gale

20

High waves occur, the sea begins to roll and dense streaks of foam form. Spray may reduce visibility.

10

48-55

Storm

20-30

Very high waves form with overhanging crests. The sea is white with densely blown foam. There is heavy rolling and lowered visibility.

11

56-63

Violent Storm 30-45

Exceptionally high waves form and foam patches cover the sea. Visibility is more reduced.

12

64+

Hurricane

Exceptionally high waves. The air is filled with foam and the sea completely white with driving spray. Visibility greatly reduced.

1-4

45

Small waves becoming longer and whitecaps are numerous.

3 Meteorologija

3.IZGLED MORA PO STEPENIMA

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4 Meteorologija

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5 Meteorologija

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6 Meteorologija

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7 Meteorologija

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8 Meteorologija

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9 Meteorologija

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S AD R ŽAJ : 1. UVOD ................................................................................................................... 2 2. BOFOROVA SKALA .......................................................................... ..............3 3. IZGLED MORA PO STEPENIMA ................................................. ..............4

1 Meteorologija

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LI T E R AT U R A: 1. Anton I. Simović - Pomorska meteorologija 2. Google