Meteorology

Using the Ship Weather Code, 1982, please code the following weather observations: Call Sign: ATVQ, Position: 06° 18'S, 015° 13'W. On 16th May GMT 20h, 20m, while on a course of 121 degrees true, at a speed of 12 knots, the barometric pressure was 998mb, Barometric tendency 4 mb, Barograph trace steadily falling, visibility 16 Km, Temperature dry=32.5°C, Wet =29.5°C, Sea water temperature: 28 degrees C, Clouds: 6/8 of the sky. True wind from north, at 16 knots, Low clouds Sc 4/8 of the sky; Ac in Chaotic Sky Ci in the form of Filaments as hooks. Present weather, continuous heavy rain, with occasional thunder and past weather overcast, with thick heavy low-lying clouds throughout. Sea state, waves 3 meters, period 12 seconds, swell from 240°(T), height 4 meters, period 15 seconds.

(a) On a course of 045° (T), at 16 knots, find the apparent wind direction and speed if a true easterly wind of 14 knots was blowing. (15)

(b) Explain what is TRUE WIND and APPARENT WIND? (10)

(a) What is HYDROLOGICAL CYCLE?

(b) Explain dew, hoarfrost & rime.

(a) Describe "CORIOLIS FORCE" and explain why it takes place?

(b) With a neat sketch explain FOHN WIND EFFECT.

(a) Describe the use of whirling psychrometer

(b) What is CARGO SWEAT and SHIP's SWEAT?

(a) Explain the weather associated with TRS.

(b) Explain the dangerous semi-circle and navigable semi-circle of TRS in "Northem" hemisphere?

Using the Ship Weather Code, 1982, please code the following weather observations:

Code the following weather report, using the Ships' Weather Code 1982.

Call Sign: ATVQ, Position: 03° 015', 015° 13'W steered a course of 090°(T) at 16 knots during last 3 hours. Estimated wind South-Westerly at 10 knots.

On 16th May GMT 13h, 40m, the barometric pressure was 998 mb, Barometric tendency 4 mb, Barograph trace steadily falling, visibility 16km. Temperature dry = 32.5°C, Wet = 29.5°C, Clouds: 6/8 of the sky. Low clouds Sc 4/8 of the sky; Ac in Chaotic Sky Ci in the form of Filaments as hooks. Present and past weather were not of significance.

(a) Differentiate between Gust & Squall

(b) On a course of 045° speed 15 knots. Apparent wind 100° at 20 knots. Find the direction speed of true wind.

(a) Short notes on Trough and Ridge.

(b) Describe the information received through facsimile weather receiver.

Describe the following:

(a) Advection Fog

(b) Radiation Fog

(c) Arctic Sea Smoke

(d) Smog

Sketch and describe aneroid barometer.

Explain the folowing ISOBARIC patterns and the weather associated with them.

(a) Col

(b) Cyclone

(c) Anticyclone

Code the following report:

Call sign ATVH, Position 09° 38'N, 068° 41'E, Course and Speed made good in last three hours 355°(T) at 18 knots. UTC time 23d 09h 28m, Wind S by W, estimated 22 knots, Visibility 1900 mtrs, Pressure 1006.8 mb, tendency (-) 2.8 mb, Barograph Trace - decreasing then steady, Temp dry bulb 30°C, wet bulb 2°C, Sea Temp 14°C. Clouds: Sky nearly overcast, low clouds 5 oktas, base 300 mtrs above sea level cumulonimbus forming an anvil. Ac resulting from cumulus, Cirrocumulus alone. Present weather Slight Drizzle, not freezing intermittent, Past Weather continuous drizzle, Sea period 05 sec, height 4 mtrs, swell from NW, period 06 sec height 4.2 mtrs.

(a) A vessel on a course of 310°(T), speed 20 knots, observes the direction of wind by looking at the line of waves as NE. The anemometer at that time showed a speed of 28 knots. State the direction in which the funnel

smoke will blow. State what direction and speed of wind is to be entered in the log book.

(b) Describe Coriolis force.

Draw a neat Sketch and explain functioning of Aneroid Barometer. What precautions are required to be taken in the care and maintenance of Barograph.

Write notes on:

(a) SALR

(b) Troposphere and Tropopause

(c) Relative Humidity

(d) Barometric tendency

(e) Isallobars

(a) Explain with neat sketch how the following clouds are formed by

(i) Convection

(ii) Orographic lifting

(b) Explain how Advection fog forms and give examples of areas where you may encounter the same at sea.

(a) Explain NE Monsoons with a neat sketch.

(b) Explain what are Cold Front and Warm Front, draw the symbols used on weather map for each? What is the weather experienced on passage of a Cold Front?

Calculate by shorter method S.H.M., height of tide at Good's Island (ATT 3) on 20th Jan 1922 at 1300 hrs.

(a) What are the conditions associated with the formation as well as movement of TRS in Northern and Southern Hemispheres.

(b) Explain the evasive actions to be taken by own vessel in the path of a TRS in Southern Hemisphere.

Define surface analysis and prognosis charts. Explain how you would use these charts for:

(a) Determination of surface winds

(b) Forecasting the movements of fronts

(c) Forecasting of sea fog

What do you understand by Fast Ice & Pack Ice? Explain with help of a sketch the diferent manners in which river water (fresh water) and sea water (salt water) freeze as air temperature falls.

Define speed, period, length and significant wave height. What is their relationship? What are the factors governing wave height and direction.

State the differences between weather routeing and climatologically routeing. Explain how you will carry out weather routeing on board your vessel.

Code the following weather report using Ship's Weather Code 1982:

Cal Sign: VQQG, Position: 00° 01'N 179° 55'E, Course made good: 179°T, Sped: 14.5 knots, Time: 12d 18h 30m GMT, Wind 048°T estimated 12 kts, Visibility: 1km, Pressure: 1003.5 mb, Barometric Tendency: +2.3 mb. Trace shows pressure increasing steadily at first and then steady.

Temperature: Dry 32.0°C, Wet 27.5°C, Sea 19.5°C.

Clouds covering 5/8th of the sky. Low clouds 3 oktas with base 500 meters above sea. Cu of strong vertical extent. Ac in chaotic sky. Cc also present.

Present weather: Thcik haze, thunderstorms.

Sea: Period 08 seconds, Height 0.5 meters

Swell: Direction 170°T, Period 10 seconds, Height 20. meters.

(a) A vessel steering 060° (T) at 15 kts, experiencing apparent wind @ 14 kts coming from 30° on port bow. Find the direction and speed of true wind.

(b) What are the various means of finding out true wind direction at sea?

What is Barometric Tendency? Sketch & describe a Barograph.

(a) Explain Fohn wind effect.

(b) Why is the diurnal range of atmospheric temperature over land is higher than that over sea/ ocean?

Explain the following:

(a) The le side of a mountain range is drier than the windward side

(b) Polar Regions are cooler than equatorial regions

(a) What is a frontal Depression?

(b) What are weather Analysis & Weather Prognosis Charts?

Decode the folowing Weather report:

BBXX | ATUX | 14183 | 99234 | 70205 | 41498

63034 | 10186 | 20152 | 29998 | 52012 | 75085

86602 | 22264 | 00170 | 21206 | 330// | 41208

(a) Write short notes on Through and Ridge.

(b) On a course of north at 11 knots, find the apparent wind direction and speed if a true easterly wind of 14 kts was blowing.

With the help of a simple sketch explain the operating principle, use, working, errors, care and maintenance of Anemometer.

Write short notes on:

(a) Classification of clouds

(b) Adiabatic Change of Temperature

(c) Occluded front

Explain as to how different type of fog can form

Explain the following:

(a) Sea and swell

(b) Tsunami

Using the Ship Weather Code, 1982, please code the following weather observations:

Call Sign: ATVQ, Position: 06° 18'S, 015° 13'W. On 16th May GMT 20h, 20m, while on a course of 121 degrees true, at a speed of 12 knots, the barometric pressure was 998 mb. Barometric tendency 4 mb, Barograph trace steadily falling, visibility 16 Km. Temperature dry = 32.5°C, Wet = 29.5°C, Sea water temperature: 28 degrees C, Clouds: 6/8 of the sky. True wind from north, at 16 knots. Low clouds Sc, 4/8 of the sky; Ac in Chaotic Sky Ci

in the form of Filaments as hooks. Present weather, continuous heavy rain, with occasional thunder and past weather overcast, with think heavy low-lying clouds throughout. Sea state, waves 3 meters, period 12 seconds, swell from 240°(T), height 4 meters, period 15 seconds.

(a) For a vessel on NE'ly course and speed of 25 Knots, an anemometer showed wind direction N by E and speed 20 knots. Find what entry is to be made in deck log book regarding wind direction and speed?

(b) Explain with a sketch the pressure gradient force and its importance.

Sketch and describe the principle and working of an aneroid barometer. Discuss advantages of its use over a mercury barometer.

List the seven isobaric patterns. Explain briefly any three of them with appropriate sketch.

Compare and contrast the weather associated with cold and warm front. Explain with sketches

(a) Discuss the various ways in which the atmosphere gains heat.

(b) Explain Green House effect.

Decode the following weather report:

BBXX | VHAN | 16003 | 99000 | 10469 | 41593

70510 | 10285 | 20208 | 40088 | 53036 | 70694

84299 | 22242 | 00206 | 20401 | 327// | 40808

(a) A vessel steering a course of 160° (T) at a speed 12 Knots, found wind speed of 10 kts from anemometer &funnel smoke was blowing towards 025° (T). Find what entry is needed in Log book.

(b) What is Buys Ballot's Law?

Draw a neat Sketch of a Barograph & label its parts.

(a) What is the difference between Isobars and Isallobars?

(b) What is barometric tendency? Explain how it can be used to predict movement of pressure systems?

(a) Write the difference between Mist & Fog.

(b) Describe various types of Fog and their formations

(a) Explain Sea breeze.

(b) Explain formation of orographic clouds.

Code the following weather observations taken on a vessel at 1750 IST on 4th January, when the vessel was at 50° 12'N 030° 17'W. Ship ATGV wind speed estimated at 42 knots.

Height of the base of the lowest cloud is 300 meters.

Horizontal visibility is 0.21 nautical miles.

The sky is fully covered by clouds

The wind is blowing from 090°(T)

Air temperature is +7.5°C, Dew point temperature is +7.2°C.

Barometric pressure is 995.2 hpa. The barometer has fallen steadily in the last 3 hour decreasing by 2.1 hpa. There is intermittent moderate rain (not freezing) at the time of observation, vessel experienced drizzle and rain since 1150 IST.

A layer of nimbostratus clouds covers the sky.

The ship's course is 270° and speed 14 knots.

The sea temperature (measured by intake) si +7.0°C.

Sea waves are estimated to be 5m high, with a period of 10 seconds, the swell waves are coming from 180°(T), height 4m, period 16 seconds.

The wet bulb temperature is +7.4°C.

(a) Vessel's course was 275 deg T and speed 14.0 knots. The wind indicated by the Anemometer was 60 deg to Starboard and the speed indicated by Anemometer was 7.0 knots. State what entry you will make in the Deck Log Book regarding True Wind?

(b) State the caution to be exercised whilst applying Buy's Ballot's Law.

Describe the Working of a Barograph with a neat sketch. Explain the care and Weekly routine on its maintenance.

Write short notes on the following:

(a) Advection Fog

(b) Cyclone

(c) CO

(d) Trough

(e) Barometric Tendency.

(a) What is semi-diurnal variation of Atmospheric Temperature? Why is the Semi-diurnal Range over land is large compared to sea?

(b) What is Relative Humidity and Dew point Temperature?

Describe FOHN Wind effect with sketch and example.

Decode the following using ships weather code 1982:

BBXX | ATJQ | 13063 | 99182 | 10823 | 41597

41228 | 10325 | 20280 | 40084 | 53031 | 79112

84149 | 22274 | 00315 | 20604 | 30406 | 41006

A vessel was steering a westerly course at 15 knots. The wind direction and speed displayed by anemometer was 060° \(R\) on port bow at 10 knots. What entry for true wind is to be made in ships logbook and weather message respectively.

Draw a neat sketch and explain the functioning of barograph. What precautions are required to be taken in its care, maintenance and its use?

Explain the folowings:

(a) Buys Ballot's law

(b) Geostrophic wind scale.

What type of cloud is likely to form when atmosphere is 'unstable'? State the features of this cloud type and list the likely weather conditions in the vicinity of and under such a cloud.

(a) Describe with sketches the process of frontogenesis.

(b) Write short notes on various weather bulletins issued by Meteorological Department for the benefit of mariners.

Code the folowing ship's full reports, using the ship's Weather Code 1982:

Date and GMT: 4 May, 1800 GMT

Ship's Call Sign: ATVH

Ship's Position: 52° 42'N , 020° 30'W

Ship's Course / speed: 180°T/ 15 knots

Wind: 080°T, speed 9 knots estimated

Weather: Cloudless, No significant phenomenon

Visibility: 8.8 nautical miles

Barometric pressure: 1020.3 mb

Barometric tendency: Increasing then increasing slowly. Changed 0.4 mb in last 3hrs.

Air temperature: +14.3°C.

Dew point temp: +6.8°C

Sea temperature: +13.0°C

Sea waves: Period 4 seconds, Height 0.8 meter

Swell: Dir. 130°T: Period 6 sec: Height 1.5 meters

(a) A vessel is steering a course 080°(T) at a speed of 12 knots. Direction of wind as obtained by observing line of sea waves was 'Westerly but apparent wind direction was 'N'. State what direction and wind speed is to be entered in the log book? Towards which direction will the funnel smoke fly?

(b) Explain Coriolis force, how it affects the winds in both Hemisphere.

Sketch and describe the working principle of precision Barometer. Explain the errors to be applied on reading obtained from the precision Barometer.

Explain following:

(a) Type and formation of fog occuring at Dover strait (English Channel) and Grand Bank of New Found land.

(b) How will you predict fog at sea?

List the different type of fog. What are the effects of fog? Explain why there is persistent fog off the Grand Banks of Newfoundland.

(a) Describe various types of information received by facsimile Weather receiver.

(b) Describe the difference between frontogenesis and frontolyes.

Code the following in a suitable format for transmission:

A ship: MV Imagine,

call sign: LGMW, position 01° 25'N, 178° 05'E, UTC time 0910, UTC date - 17 June,

SMT 2110, Course made good in last 3 hours 165°,

speed: 17 kts,

estimated wind: 136° at 14,

visibility 16 KM,

atmospheric pressure: 987.6 hpa,

barometric tendency: +2.5 hpa, increasing steadily. Temp: dry 28.0°C,

wet: 23.0°C,

sea: 22°C,

clouds: fully covered with clouds except for few blue patches,

low cloud cover: 4 oktas,

base 1000 M above sea,

Cu of little vertical extent and seemingly flattened,

Ac of chaotic sky, Cc alone.

Present wx: State of sky on the whole unchanged,

past wx: - cloud covering more than 1/2 of the sky throughout the appropriate period, rain. Sea period 07 sec, height: 03 mtrs, Swell coming from east period 7 sec, height: 03 mtrs.

(a) Vessel's course 275°T, speed 14 kts, the wnid direction and speed displayed by the anemometer was Stbd 060° and 7kts. What entry for true wind is to be made in the logbook?

(b) Explain what is pressure gradient force and Coriolis force.

Describe construction, working and errors of Aneroid Barometer.

(a) List different types of fog.

(b) Explain why there is persistent fog off the Grand Banks of New foundland.

(a) Define Fog & Mist & explain how it is formed.

(b) Explain Land & Sea Breeze.

Sketch and describe the lifecycle of a frontal depression. What kind of weather will be encountered during passage of cold front?

Code the following ship's full reports, using the ship's Weather Code 1982.

Date and GMT: 4 May, 1800 GMT

Ship's Call Sign: ATVH

Ships' Position: 52° 42'N, 020° 30'W

Ships' Course /Speed: 180°T/ 15 knots

Wind: 080°T speed 9 knots estimated

Weather: Cloudless. No significant phenomenon

Visibility: 8.8 nautical miles

Barometric pressure: 1020.3 mb

Barometric tendency: Increasing then increasing slowly. Changed 0.4 mb in last 3 hrs.

Air temperature: +14.3°C

Dwe point temp: +6.8°C

Sea temperature: +13.0°C

Sea waves: Period 4 seconds: Height 0.8 meter

Swell: Dir. 130°T: Period 6 sec: Height 1.5 meters.

(a) Course 295° speed 16 knots out in open sea. Wind force 4 (18 knots) estimated by appearance of the sea surface. Smoke from the funnel was observed to be blowing to NNE. What entry is to be made in the weather report with respect to wind direction and speed

(b) What is Coriolis force? How does it affect the wind blowing over sea and land.

With the help of a neat sketch describe the functioning of an Aneroid barometer, what are the errors possible? List precautions to be taken while using the same?

Describe in detail seven basic isobaric patterns with the help of suitable sketches.

Explain the "Formation of clouds" due to following:

(a) Turbulence

(b) Convection

Enumerate the weather associated with warm front, cold front and occluded front. Draw the symbols used in weather charts to depict these fronts.

Code the following weather report:

Ship's Name: S Loyalty,

Call Sign: LGMW,

Posn 01° 25'S 178 °05E'.

Date: 17 June, SMT: 210,

CMG & SMG NI Last 3hrs: 165 (T), 17 kn. Estimated

Wind: 136 (T), 14 kts, Visibility: 16 Km,

Atmospheric pressure: 987.6 hpa,

Barometric Tendency: +25. hpa increasing steadily.

Temperature: dry: +28°C, Wet: +23°C, Sea: +22°C.

Cloud: Fully covered sky with few blue patches, low clouds cover 4 oktas, base 1000 meters, above sea, Cu with litle vertical extent and seemingly flatened, Ac in a chaotic sky, Cc alone.

Present Wx: State of Sky on the whole unchanged.

Past Wx: Cloud covering more than 1⁄2 of sky throughout period, rain.

Sea period: 07 sec, height 1.5 mtrs, swell coming from south east, period 7 sec, height 3 mtrs.

A vessel steaming due east at 19 knots in open sea, observes the sea surface and estimates the wind force to be lower limit of force 6 (22 knots). A handkerchief held up was observed to blow towards south. State what entry is to be made in the weather report regarding wind direction and speed?

Describe basic principle and working of Aneroid barometer. What are the correction to be applied to its reading before making entry in deck log book? Why Aneroid barometer is preferred over mercury barometer for use on board the ship?

Explain the following:

(a) Type and formation of fog occuring at Dover strait (English Channel) and Grand Bank of New Found land.

(b) How will you predict fog at sea?

Describe with sketch formation of:

(a) NE Monsoon

(b) Land and Sea breeze

Describe with sketch the process of frontogenesis. What type of weather is associated with cold front and warm front?

Code the following ship's full reports, using the ship's Weather Code 1982.

Date and GMT: 4 May, 1800 GMT

Ship's Call Sign: ATVH

Ships' Position: 52° 42'N, 020° 30'W

Ships' Course /Speed: 180°T/ 15 knots

Wind: 080°T speed 9 knots estimated

Weather: Cloudless. No significant phenomenon

Visibility: 8.8 nautical miles

Barometric pressure: 1020.3 mb

Barometric tendency: Increasing then increasing slowly. Changed 0.4 mb in last 3 hrs.

Air temperature: +14.3°C

Dwe point temp: +6.8°C

Sea temperature: +13.0°C

Sea waves: Period 4 seconds: Height 0.8 meter

Swell: Dir. 130°T: Period 6 sec: Height 1.5 meters.

(a) A vessel is steering a course 080°(T) at a speed of 12 knots. Direction of wind as obtained by observing line of sea waves was 'Westerly' but apparent wind direction was 'N'. State what direction and wind speed is to be entered in the log book? Towards which direction will the funnel smoke fly?

(b) Explain Coriolis force, how it affects the winds in both Hemisphere.

Describe Basic principle and working of Aneroid barometer. What are the correction to be applied to its reading before making entry in deck log book? Why Aneroid barometer is preferred over mercury barometer for use on board the ship?

Explain the following:

(a) Type and formation of fog occuring at Dover strait (English Channel) and Grand Bank of New Found land.

(b) How will you predict fog at sea?

(a) Describe with sketch Katabatic and Anabatic wind.

(b) Describe with sketch SW Monsoon.

(a) Describe the classification and properties of air masses.

(b) What are the factors affecting the properties of an air mass?

Code the following weather observations taken on a vessel at 1750 IST on 4th January, when the vessel was at 50° 12'N, 030° 17'W.

Ship: ATGV, wind speed estimated at 42 knots.

Height of the base of the lowest cloud is 300 meters.

Horizontal visibility is 0.21 nautical miles.

The sky is fully covered by clouds.

The wind is blowing from 090°(T)

Air temperature is +7.5°C, Dew point temperature is +7.2°C .

Barometric pressure is 995.2 hpa. The barometer has falen steadily in the last 3 hour decreasing by 2.1 hpa

There is intermittent moderate rain (not freezing) at the time of observation, vessel experienced drizzle and rain since 1150 IST.

A Layer of nimbostratus clouds covers the sky. The ship's course is 270° and sped 14 knots.

The sea temperature (measured by intake) is +7.0°C.

Sea waves are estimated to be 5m high, with a period of 10 seconds, the swell waves are coming from 180°(T), height 4m period 16 seconds. The wet bulb temperature is +7.4°C.

(a) On a course of 154° at 13 knots an anemometer on the bridge showed a wind speed of 23 knots. The

direction of wind by observing line of waves was WSW. What entry is to be made in the weather report with respect to wind direction and speed? If an observer on the vessel threw up a piece of paper in which

direction would it fly off?

(b) State Buy Ballot's Law. Explain the precautions to be observed when applying Buy Ballot's Law.

Sketch and describe the whirling Psychrometer. What are the advantages of the whirling psychrometer over the hygrometer?

What are isobars and how are they used to predict weather? With suitable sketches describe any THREE isobaric patterns and the weather associated with them.

Write short notes on the following:

(a) DALR

(b) Sea

(c) TICZ

(d) Warm front

(a) Describe the classification and properties of air masses.

(b) What are the factors affecting the properties of an air mass?

Code the following ship's full reports, using the ship's Weather Code 1982.

Date and GMT: 4 May, 1800 GMT

Ship's Call Sign: ATVH

Ships' Position: 52° 42'N, 020° 30'W

Ships' Course /Speed: 180°T/ 15 knots

Wind: 080°T speed 9 knots estimated

Weather: Cloudless. No significant phenomenon

Visibility: 8.8 nautical miles

Barometric pressure: 1020.3 mb

Barometric tendency: Increasing then increasing slowly. Changed 0.4 mb in last 3 hrs.

Air temperature: +14.3°C

Dwe point temp: +6.8°C

Sea temperature: +13.0°C

Sea waves: Period 4 seconds: Height 0.8 meter

Swell: Dir. 130°T: Period 6 sec: Height 1.5 meters.

(a) Vessel's course 170°T, speed 15kts, the wind direction and speed displayed by the anemometer was port 045° and 12 kts. What entry for the true wind is to be made in the ship's logbook?

(b) Describe the ideal pressure and wind distribution on earth's surface assuming earth fully covered by water.

Sketch and describe the working principle of precision Barometer. Explain the errors to be applied on reading obtained from the precision Barometer.

Define Isobar and how they used ot predict weather. With suitable sketch, describe any three Isobaric patterns and weather associated with them.

List the different types of fog. What are the effects of fog? Explain why there is persistent fog of the Grand Banks of Newfoundland.

Explain the following in details:

(a) Advantages of shore based weather Routeings.

(b) Why the lower latitudes areas are warmer than higher latitude areas.

Encode the following Weather report from a ship station:

Ship: AWKG,

Position: 06° 12.5'S, 084° 43'E,

course made good over last three hours: 120° at 13 knots, GMT: 23d 00h 20m,

Wind: Northerly estimated at 11 knots, Visibility: 700 Mtrs.

Pressure: 1011 hpa,

Tendency: +36. hpa,

Barograph trace: Increasing then decreasing.

Temperature: Dry 23.5°C, Wet 21.0°C, Sea base 800 mtrs above sea level, Cu of moderate or strong vertical extent, Ac in a Chaotic sky, Cc.

Present Weather: Visibility poor due to dust in suspension in the air, not raised by wind at or near ship.

Past Weather: drizzle rain.

Sea: Period 08 seconds, height 2.0 mtrs. Swell: From 220°, Period 10 seconds, height 5.0 mtrs.

(a) A vessel is steering a course 080°(T) at a speed of 12 knots. Direction of wind as obtained by observing line of sea waves was 'Westerly' but apparent wind direction was 'N'. State what direction and wind speed is to be entered in the log book? Towards which direction will the funnel smoke fly?

(b) Explain Coriolis force, how it affects the winds in both Hemisphere.

Describe Basic principle and working of Aneroid barometer. What are the corrections to be applied to its reading before making entry in deck log book? Why Aneroid barometer is preferred over mercury barometer for use on board the ship?

Explain the following:

(a) Type and formation of fog occurring at Dover strait (English Channel) and Grand Bank of New Found land.

(b) How will you predict fog at sea?

Explain with the help of neat sketches the formation and classification of different types of clouds as per height.

(a) Describe the classification of properties of air masses.

(b) What are the factors affecting the properties of an air mass.

Code the following weather report:

Ships' Name: S Loyalty,

Call Sign: LGMW,

Posn 01° 25'S, 178° 05'E.

Date: 17 June, SMT: 2110,

CMG & SMG in Last 3 hrs: 165 (T), 17 kn.

Estimated Wind: 136 (T), 14 kts, Visibility: 16 Km, Atmospheric pressure: 987.6 bpa,

Barometric Tendency: +2.5 hpa increasing steadily.

Temperature: dry: +28°C, Wet: +23°C, Sea: +22°C.

Cloud: Fully covered sky with few blue patches, low clouds cover 4 oktas, base 1000 meters, above sea, Cu with litle vertical extent and seemingly flattened, Ac in a chaotic sky, Cc alone.

Present Wx: State of Sky on the whole unchanged.

Past Wx: Cloud covering more than 1⁄2 of sky throughout period, rain.

Sea period: 07 sec, height 1.5 mtrs, Sweel coming from south east, period 7 sec, height 3 mtrs.

(a) Own vessel was on course NE by E proceeding at 114 Knots. By observing sea waves wind speed was estimated to be Force 5 (18 kts) and funnel smoke was blowing towards WNW. State what entry to be made in log book regarding wind direction and speed.

(b) Describe Buys Ballot's Law and its limitations.

Sketch and describe the principle and working of Wind vane and Anemometer. List its error, care and maintenance for same.

Define Isobar and how are they used to predict weather. With suitable sketch, describe any three Isobaric patterns and weather associated with them.

(a) Describe with Sketch Katabatic and Anabatic Wind.

(b) Describe with Sketch SW Monsoon.

(a) Describe various types of information received by facsimile Weather receiver.

(b) Describe the difference between frontogenesis and frontolyes.

Code the following weather observed taken on vessel at 1750 IST on 4th January, when vessel was at 50° 12'N, 0 30 ° 17'W, Ship ATGV, Wind speed 42 Knots .

Height of the base of the Lowest Cloud is 300 Mts.

Horizontal Visibility 0.21 nautical miles. The sky is fully covered by clouds.

The wind is bolwnig from 090°, Air temp. +7.5°C, Dew point Temperature +7.2°C.

Barometric Pressure is 995.2 hPa. The barometer has fallen steadily in the last three hours deceasing by 2.1 hPa. There is intermittent moderate rain (not freezing) at the time of observation: Vessel experienced drizzle and rain since 1150 Hrs IST. A layer of Nimbostratus cloud covers the sky. The ship course is 270° and the speed 14 Knots. The sea temperature (measured by intake) is +7.0°C. Sea waves are estimated to be 5 mts high, with aperiod of 10 seconds, the swell waves are coming from 180°, height 4 mts period 16 seconds. The wet bulb temperature is +7.4°.

(a) Draw a neat sketch illustrating Fohn Wind Effect.

(b) Ship course SW by W at 12 kts. True Wind observed to be 2 points abaft the starboard beam. The funnel smoke was blowing in a direction 3 points abaft port beam. Find the speed of the true and apparent wind and state what entries will be made in ship's log book and weather report.

Describe Basic principle and working of Aneroid barometer. What are the correction to be applied to its reading before making entry in deck log book? Why Aneroid barometer is preferred over mercury barometer for use on board the ship?

Write short notes on the following (Any four)

(a) Anabatic wind

(b) Fohn Wind

(c) Relative and Absolute Humidity

(d) Isobars and Isallobars

(e) High Latitude depression.

(a) Explain what you understand by cold front, warm front and occluded front and how these fronts are formed.

(b) Discuss weather that are associated with each of the above kind of fronts.

(c) Give necessary diagram.

(a) Explain how advection fog is formed. Give some example of the region where advection fog forms.

(b) Difference between Synoptic and Prognostic Charts?

Code the following Ship's Weather Observation:

Shpi: VHAN, Position: 00° 05'N 46° 58'E,

Course made good past 3 hours 170° at 10 Knots,

GMT 16d 00h 20m, Wind 052° estimated at 10 knots.

Visibility 500 mts, Pressure 1008.8 mbs, Tendency +3.6 mbs, Baro, Trace.

Temperature: Dry 28.5°C, Wet 23.0°C, Sea 20.6°C

Cloud: Sky Over Cast with few blue Patches. Low clouds 4 oktas, base 600 metres, above Sea,

Cu of strong vertical extent, Ac in a chaotic sky, Cc.

Present Weather: Visibility Poor due to dust in suspension in the air, not raised by wind at or near ship. Past Weather Thick Haze, thunderstorm.

Sea: Period 04 Seconds, height 0.4 metres. Swell: Form 270° period 08 Second, height 0.4 metres.

Draw a neat Sketch of "Precision Aneroid Barometer" &enumerate the corrections applicable.

(a) On a vessel steering 115° at 16 kts, in open sea. Anemometer / Wind vane showed wind coming from 45° on starboard bow with sped of 9m/s. State the entry you will make in the deck log regarding wind and also state the direction in which the funnel smoke will fly.

(b) Explain Foha Wind with a neat sketch.

What do you mean by the term "Air-Masses"? Explain Cold front and warm front in terms of movement of cold / warm air masses. Sketch and describe the life cycle of a frontal depression. What kind of weather will be encountered during passage of Cold front?

(a) How clouds are formed? Discuss about various types of Low clouds.

(b) Discuss formation of clouds by Turbulence and convection.

Write short notes:

(a) Geostrophic Wind and Geostrophic Wind Scale

(b) Anticyclone

(c) Radiation Fog

(d) Katabatic Winds

(e) Doldrums

Code the following weather observations taken on a vessel at 1750 IST on 4th January, when the vessel was at 50°12'N 030° 17'W

Ship: ATGV, wind speed estimated at 42 knots

Height of the base of the lowest cloud is 300 meters

Horizontal visibility is 0.21 nautical miles

The sky is fully covered by clouds

The wind is blowing from 090°(T)

Air temperature is +7.5°C, Dew point temperature is +7.2°C.

Barometric pressure is 995.2 hpa. The barometer has fallen steadily in the last 3 hour deceasing by 2.1 hpa.

There is intermittent moderate rain (not freezing) at the time of observation, vessel experienced drizzle and

rain since 1150 IST.

A layer of nimbostratus clouds covers the sky.

The ship's course is 270° and speed 14 knots.

The sea temperature (measured by intake) is +7.0°C.

Sea waves are estimated to be 5m high, with a period of 10 seconds, the swell waves are coming from 180°(T), height 4m, period 16 seconds.

The wet bulb temperature is +7.4°C.

(a) On a course of 154° at 13 knots, an anemometer on the bridge showed a wnid sped of 32 knots. The direction of wind by observing line of waves was WSW. What entry is to be made in the weather report with respect to wind direction and speed? If an observer on the vessel threw up a piece of paper, in which direction would it fly off?

(b) State Buy Ballot's Law. Explain the precautions to be observed when applying Buy Ballot's Law.

Sketch and describe the whirling Psychrometer. What are the advantages of the whirling psychrometer over the hygrometer?

What are isobars and how are they used to predict weather? With suitable sketches describe any THREE isobaric patterns and the weather associated with them.

Differentiate between the following:

(a) Gust and Squall

(b) Sea and Swell

(c) Veering and Backing

(a) Describe the classification and properties of air masses.

(b) What are the factors affecting the properties of an air mass?

Encode the following weather report from a ship station:

Call sign, VPY, position 28° 08'N, 160° 32'E, course made good over last 3 hours 265°T at 14.2 knots, GMT 25th Day, 18 hrs 00 min, wind north-east estimated at 14, visibility 2000m, pressure 1004mm, tendency - 1.5 mm, barograph trace, increasing then decreasing, dry temperature 30.5°C, wet 26.2°C, clouds: sky o'cast with few blue patches, clouds 6-oktas, base 600m above sea level, Cumulus of strong vertical extent, Alto-cumulus in a chaotic sky, Present weather: poor visibility due to rain, Past weather: Drizzle and rain, Sea: Period 4 seconds, sea wave height 2 meter, Swell direction from 160°T, period 8 seconds, wave height 3m.

(a) Vessel course 235°T, speed 15 knots. The anemometer shows wind direction 223°T at 10.4 knots. Calculate true wind direction and speed.

(b) State Buys Ballot's law and its applications.

Define dew point. Describe its application in hold ventilation on ships. How is dew point obtained and which instruments are used for this?

(a) What is the difference between Isobars and Isallobars?

(b) What is barometric tendency? Explain how it can be used to predict movement of presure systems?

Describe the formation of fog, and list its types with brief description of each. Explain why there is persistent fog of the Grand Banks of Newfoundland.

Define Isobars. List and describe various Isobaric Patterns.