Meteorology

Ten generic-module questions: cyclones, currents and general circulation.

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Tropical cyclones

Northern Hemisphere: dangerous semicircle to the right of the track. Southern Hemisphere: to the left.

Coriolis deflects to the right in the Northern Hemisphere and to the left in the Southern.

Currents

In the North Atlantic circulation is clockwise. The Gulf Stream is warm. The Benguela Current is cold.

Activities

• Weather visualsClouds, fog, isobars, breezes and sea state.
• Read the skyCheck the sky, barometer and wind. What is coming?

Questions in this unit

• The North Atlantic winds that blow from the Canary Islands towards the Caribbean, passing the Cape Verde Islands, are called:
• The so-called Prevailing Westerlies of the South Atlantic blow from:
• In fully formed hurricanes and cyclones, the predominant clouds are:
• The Benguela Current, running along the Atlantic west coast of South Africa and reaching Namibia in the tropics, is:
• What is the layer of the atmosphere called where atmospheric phenomena occur that matter to the mariner?
• The jet stream winds occur:
• If a northern hemisphere cyclone or hurricane catches us in its navigable semicircle, given the winds, the yacht will tend to:
• Sailing in cyclone and hurricane areas, which clouds can go with the first signs that a cyclone or hurricane is coming?
• If two air masses (one cold, one warm) come into contact, this will produce:
• On a line of strong atmospheric instability, the clouds produced will be:
• Floating ice that forms on the sea surface when it freezes is called:
• The part of floating ice showing above the sea is:
• The “Doldrums zone” is:
• The air masses interacting in the intertropical convergence zone (ITCZ) are:
• Regarding the intensity of the winds, their force and devastating effects, the scale measuring cyclones and hurricanes is:
• In the Indian Ocean, sailing the Bay of Bengal NE of Sri Lanka in June, we will be in the season of:
• The Benguela marine current in the Atlantic Ocean is:
• The “halo or corona” phenomenon occurs with the Sun or Moon, forming a circle around them, and goes with:
• In the North Atlantic, the trade wind regime circulates through:
• In the North Atlantic, the winds known as Prevailing Westerlies blow:
• When one air mass comes into contact with another of warm, humid air, this produces:
• Waterspouts form from a characteristic type of cloud, which is:
• When inside a warm front, with much humidity and a milky veil in the sky, what is seen around the Sun or Moon is:
• The air in the Earth’s atmosphere is made up of various gases. The most abundant is:
• If we see the Sun or Moon surrounded by a circle of faint, diffuse rainbow colours, we are seeing:
• At the centre or vortex of a hurricane or cyclone, the sea is:
• In the northern hemisphere, among other things, in the dangerous forward sector of a hurricane:
• The “halo” photometeor is characterised by:
• Cyclones or hurricanes follow typical tracks...
• Halos or coronas around the Sun or Moon occur when...
• Sailing a large motor yacht in the South Indian Ocean, from the Seychelles to Mauritius, halfway we are caught by a cyclone in its dangerous forward sector. The manoeuvre would be...
• Showers: the air masses interacting in them are...
• The North Atlantic current flowing south from the coast of Galicia to Cape St Vincent in southern Portugal is called:
• Land-origin ice that falls into the sea and drifts with currents forms:
• Lightning and its flash occur when:
• On waterspouts and tornadoes:
• Sailing the Indian Ocean in July, Fremantle cyclone centre warns that a cyclone is approaching. Which clouds will precede it?
• The tropopause is the layer of the atmosphere that joins:
• The strong suction of warm air rising from the sea surface in a cyclonic spin towards a cumulonimbus produces:
• North Atlantic hurricanes blow and travel from:
• Meteorologically, the most active zone of the atmosphere is:
• On waterspouts and tornadoes:
• When a squall of rain and strong wind forms and develops:
• The atmosphere has a layer about 150 km up that reflects short and medium electromagnetic waves back down, not letting them escape to space. It is called:
• When two adjacent clouds have different electric charges, what may happen?
• The characteristic wind regimes of the Indian Ocean are:
• What is the jet stream?
• Studies and analyses for weather information are done mainly in the atmospheric layer:
• When a line of instability appears on the weather map, it is because:
• With an instability line on the weather map, the clouds in that area are:
• Cyclones and hurricanes are measured on the international scale:
• If in the tropical North Atlantic a hurricane catches us in its dangerous forward sector, this will mean:
• In the North Atlantic, icebergs appear in time and area:
• In cyclones or hurricanes the isobars appear:
• When a squall with strong winds and heavy rain forms, there is:
• The Atlantic Canary current flows:
• In a cyclone in the Indian Ocean south of the equator, we are in its dangerous semicircle if we are:
• If transmitting on short wave from our yacht, these waves are reflected by the atmospheric layer:
• In polar waters you see ahead an iceberg rising 11 metres above the surface. Its submerged part will be about:
• In both hemispheres, cyclones or hurricanes form between the parallels of:
• In the tropical North Atlantic, caught in a hurricane’s dangerous sector, the winds will tend to:
• Zodiacal light is an optical glow in the sky during astronomical twilight. It occurs when:
• In the North Pacific, the prevailing westerlies blow:
• In a line of instability with strong storms and lightning, if we hear a loud bang, the sound is:
• The Labrador current (North Atlantic), flowing from north to south, runs:
• In the North Atlantic, caught in a hurricane’s navigable semicircle, the winds will tend to:
• Within a storm, lightning occurs because:
• Once sea ice forms, the surface sheet it makes is called:
• Waterspouts and tornadoes form:
• North Atlantic hurricane tracks run east to west, following the general wind circulation from...
• If St Elmo’s fire appears on our yacht, it could be the prelude to…
• The front separating polar from tropical air masses is called the:
• The optical illusion caused by total reflection of light passing through air layers of different density is called:
• In a Northern Hemisphere tropical cyclone, if we are in the dangerous rear semicircle, to get out we steer to…
• Submerged ice attached or anchored to the bottom, whatever its origin, is called…
• The “tropical calms” zone…
• Accumulations of floating ice made of fragments under 2 m across, from the wreck of other ice, are called:
• The low-pressure belt girdling the globe in the equatorial region, formed by the convergence of warm moist air north and south of the Equator, is called:
• When two air masses in contact are in unstable equilibrium, what will develop is…
• The troposphere is the layer of the Earth’s atmosphere that is…
• The general circulation of the North Atlantic trade winds runs:
• Under IMO SOLAS Chapter V rules on ice navigation, the limit for the presence of ice in the waters of the South Pacific Ocean is set:
• The World Meteorological Organization uses a scale to classify the strength and intensity of cyclones or hurricanes, known as the:
• Cyclones or hurricanes are defined as:
• Radio waves, and above all short wave (HF) and medium wave (MF), are reflected in the atmospheric layer called the:
• If on the weather chart we observe a marked instability line, what is taking place in that zone is:
• When two air masses interact, but one of them returns to its original state, the expected evolution is:
• Waterspouts are produced:
• The optical phenomenon of the solar corona is due to:
• Hurricanes in the North Atlantic follow a track that runs:
• The rules and standards established for safe navigation in waters with ice are set out in:
• If sailing in November from the Canary Islands towards the Caribbean, the prevailing wind in that area of the Atlantic Ocean will be:
• Through the warming of sea water, especially in the Mediterranean between May and October, a column of warm, low-density air forms in cumulonimbus clouds and rises spinning anticlockwise, giving rise to:
• A glow in the sky during astronomical twilight (especially in the evening), seen after the Sun sets below the horizon along the plane of the ecliptic or zodiacal belt, is known as:
• The phenomenon similar to cyclones or hurricanes that forms north of Australia is known as a:
• In the Northern Hemisphere, icebergs drift out to sea mainly in:
• Which is the layer of the Earth’s atmosphere where medium-wave (MF) and short-wave (HF) radio waves are reflected?
• Floating ice of the pack-ice (ice-pack) type has its origin in:
• The origin of a thunderstorm formation is the result of:
• Both in thunderstorms and in the formation of waterspouts, the clouds involved are of the type:
• In the North Atlantic Ocean, hurricanes track from the Cape Verde archipelago off West Africa towards the Caribbean in the season of:
• The so-called Intertropical Convergence Zone lies:
• The optical phenomenon of a halo or corona takes place when:
• The Earth’s atmosphere is composed mainly of nitrogen, oxygen, argon and carbon dioxide. Which of these gases makes up the largest share of the atmosphere?
• In the North Atlantic, the trade winds blow:
• In the vortex of a hurricane or cyclone, the state of the sea will be:
• The North Atlantic current called the “Portugal Current” runs:
• From which direction do the trade winds blow in the Southern Hemisphere?
• What safety precaution should we take when sailing among ice?
• The layer of the Earth’s atmosphere where the jet stream acts is:
• The isobars in a tropical cyclone or hurricane appear:
• The number of intensity categories for a cyclone or hurricane on the international Saffir–Simpson scale runs from:
• The layer of the atmosphere in which most weather phenomena occur is called the:
• Squalls and showers are usually associated with…
• The polar front is defined as:
• The Saffir–Simpson scale is characterized by:
• What safety precautions must be kept if sailing among drifting ice?
• The atmospheric layer holding the “ozone layer” is called:
• A characteristic feature of squalls and showers is that…
• The areas called the “equatorial calms” (Doldrums) are characterized by:
• For a tropical cyclone to form, it is necessary that…
• Which of the following pairs are North Atlantic currents?
• If we are sailing in an area with drifting ice, we will:
• The zone that separates the northern hemisphere equatorial air from its southern counterpart is called the:
• In winter, the continental monsoon blows:
• What condition must exist for the track of a tropical cyclone, instead of recurving, to remain almost straight?
• Where do low pressures prevail with strong rising air currents?
• If you are in the Southern Hemisphere in the dangerous semicircle of a tropical cyclone, to get out of it you should steam at the highest speed circumstances allow and:
• Sailing near ice, as a general rule it is advisable to pass it:
• To manoeuvre away from a tropical cyclone in the Northern Hemisphere, if the wind shifts clockwise you should keep the wind:
• Up to about 35 km altitude, the most abundant gases in the atmosphere are:
• St Elmo’s fire is characterized by:
• The Intertropical Convergence Zone is characterized by:
• The Equatorial Countercurrent:
• The Saffir–Simpson hurricane scale:
• Regarding tropical cyclones:
• Into which current does the Trade Wind Current (Corriente del Alisio) feed?
• The polar winds in both hemispheres:
• Continental monsoons are characterized by:
• In a Southern Hemisphere tropical cyclone, if at our position the winds shift anticlockwise:
• The natural discharge of static electricity produced during a thunderstorm is called:
• To estimate the future track of a tropical cyclone and avoid it:
• South of 20º N latitude, the Canary Current:
• Regarding the formation of a tropical cyclone:
• Regarding the Polar Front, which statement holds?
• The belts lying between the trade winds and the westerlies are called:
• Regarding the origin of ice, icebergs are of what origin?
• Up to 80 km altitude, the Earth’s atmosphere has a roughly uniform composition in which Nitrogen (N) makes up by volume:
• If we are sailing in polar zones and meet ice, the proper manoeuvre to pass it is:
• Mark the FALSE statement concerning the Zone of Equatorial Calms:
• The cyclonic weather phenomenon consisting of a rapidly rotating air column whose lower end touches the land surface and whose upper end connects to a cumulonimbus cloud, of small diameter and short duration, is called a:
• The general surface current of the Mediterranean Sea:
• Concerning atmospheric electrical phenomena:
• Which statement is true of the Intertropical Convergence Zone?
• Regarding the seasonal position of the Polar Front:
• Concerning the Intertropical Convergence Zone, choose the right option:
• Regarding the Polar Front and its activity:
• On ocean currents, mark the correct option:
• With respect to sea ice and icebergs:
• Concerning the composition of the atmosphere, mark the true option:
• Regarding the Intertropical Convergence Zone, mark the FALSE option:
• In summer, the continental monsoon blows:
• On tropical cyclones, mark the correct option:
• On the currents of the Atlantic Ocean, mark the correct option:
• Regarding the drift of sea ice and icebergs, mark the true option:
• About the Earth’s atmosphere and its gases, mark the true option:
• On the currents of the North Atlantic, mark the correct statement:
• The direct continuation of the Canary Current is:
• About the atmosphere, mark the FALSE option:
• In a tropical cyclone, if the winds shift anticlockwise:
• Regarding types of sea ice, mark the correct option:
• On ice navigation and sea ice, mark the FALSE option:
• With respect to tropical cyclones, mark the correct statement:
• In relation to Atlantic ocean currents, mark the correct option:
• On the composition and structure of the atmosphere, mark the correct option:
• Regarding the Intertropical Convergence Zone (ITCZ), mark the correct option:
• Regarding major ocean currents, mark the correct option:
• In relation to the Polar Front, mark the correct option:
• Concerning the Polar Front, mark the true statement:
• Concerning sea ice and icebergs, mark the correct option:
• In relation to ocean currents, mark the FALSE option:
• The front that separates polar air masses from tropical air masses is called the:
• In relation to glacier ice and sea ice, mark the correct option:
• With respect to the zone of tropical calms, mark the correct option:
• The strong electrical discharges in the atmosphere within clouds or between a cloud and the Earth’s surface are known as:
• The North Equatorial Current:
• The Benguela current:
• In the region of Tropical Calms:
• What is the prevailing direction of polar winds?
• Tropical cyclones in the North Atlantic form in:
• In World Meteorological Organization terms, “ice under pressure” refers to:
• From the subtropical highs towards the subpolar lows, at middle latitudes, we find winds:
• Icebergs:
• The percentage of oxygen in the composition of the atmosphere is:
• Concerning the ITCZ (Intertropical Convergence Zone), mark the true statement:
• Regarding glacier and sea ice terms, mark the correct option:
• In relation to navigation in ice zones, mark the correct option:
• About the formation of tropical cyclones, mark the correct option:
• On the surface currents of the Atlantic, mark the correct statement:
• In relation to monsoons, mark the correct option:
• On the Polar Front and its depressions, mark the correct option:
• Mark the ocean current that does NOT flow in the Atlantic Ocean:
• With respect to ice terminology, mark the FALSE option:
• About the currents in the North Atlantic, mark the correct option:
• The winds in the left semicircle of a cyclone in the Northern Hemisphere:
• With respect to ice classifications, mark the correct option:
• With respect to the Intertropical Convergence Zone, mark the correct option:
• About the gas composition of the atmosphere, mark the correct option:
• In relation to floating and coastal ice, mark the correct option:
• Concerning the composition of the atmosphere, mark the true statement:
• A luminous ring centred on the Sun or Moon, usually whitish though sometimes showing spectral colours, is called a:
• What is the name of the first zone of the atmosphere from which temperature stops decreasing with height?
• Frontal rains are defined as those:
• What should we do when sailing near drifting ice?
• In a tropical cyclone, the dangerous and navigable semicircles lie:
• The typical tracks followed by tropical cyclones in the Northern Hemisphere run towards the:
• The trade winds in the North Atlantic blow:
• When a loud bang is heard in a storm, this sound phenomenon is called:
• The Saffir-Simpson scale classifies tropical cyclones into:
• The faint glow in the sky during astronomical twilight, in the plane of the ecliptic, is known as:
• To identify thunderstorms, bear in mind that:
• In the life cycle of a tropical cyclone, when the pressure stabilises at a very low value, around 950 mb on average, what stage is it in?
• The Intertropical Convergence Zone:
• In general, a mirage is a result of:
• What pressure fall must a mid-latitude low show to be considered “explosive cyclogenesis”?
• Sailing on the high seas from the North Pole towards the Equator on a southerly course, between about 60ºN and 30ºN, the winds will generally come from our:
• The Enhanced Fujita scale:
• The Loop Current:
• The Intertropical Convergence Zone is:
• The jet stream:
• According to the World Meteorological Organization, what is the correct definition of “close pack ice”?
• In an area of showers:
• Floating ice of land origin that reaches the sea and drifts in it is:
• Waterspouts:
• The trade winds:
• The “Fata Morgana” is:
• What should be done if, under way, we meet an area of thick, fast-drifting ice?
• If, in an ice area, a ship’s master must send a danger message on meeting ice dangerous to navigation, what information need NOT be included?
• We are sailing in the Indian Ocean between Indonesia and Australia, in a tropical cyclone, with the wind increasing and veering clockwise. The most reasonable manoeuvre is:
• Tornadoes:
• In general, the least dangerous quadrant in a tropical cyclone’s area of influence in the Southern Hemisphere is the:
• In general, in which part of the Atlantic do the main ocean currents circulate anticlockwise?
• If a ship’s master in an ice area meets ice of which no official warning has been received, they must send the danger message:
• The term “drift ice” applies when ice:
• Among electrical, acoustic and optical phenomena, thunder is a:
• In a cyclone, if the wind veers clockwise:
• The master of any ship told of ice on or near their route:
• Thunderstorm forms are associated with clouds of the type:
• What is an “ice shelf” (meseta de hielo)?
• In the Northern Hemisphere, a cyclone’s usual track is roughly:
• A parhelion:
• In ice navigation, what is an “area of weakness”?
• The layers of the atmosphere, from nearest to furthest from the Earth’s surface, are:
• Currents caused by the pull of the Moon and Sun are called:
• The trade winds blow from a subtropical anticyclone towards:
• Regarding tropical cyclones, which statement is INCORRECT?
• According to the World Meteorological Organization, “dried ice” is:
• What is the luminous ring around the Sun or Moon called, whitish or spectral, caused by refraction of its light in the ice crystals of high clouds?
• On 25 June 2022 the last observed position is 15º 06′N 056º 30′W, ship’s time 17:00, about 300 miles east of Dominica. With force 12 conditions and no way of getting forecasts, a cyclone is suspected. If the wind veers clockwise and the barometer is falling, in what part of the cyclone are we?
• The three main components of the atmosphere are:
• The Spitsbergen current:
• According to the general wind systems, the prevailing westerlies of the North Atlantic blow:
• If, under way, we meet ice, or air temperatures below freezing with strong winds causing a heavy build-up of ice on the vessel, we are required to send the information by all available means to:
• When a cold air mass meets a warm one, an instability line appears, with warm updraughts and towering cumulonimbus. What weather will the sinking cold air bring?
• The layer of the atmosphere in contact with the Earth’s surface is the:
• We are sailing at latitude 25°N in the Atlantic, in a tropical cyclone, with the wind veering clockwise. The safest manoeuvre is:
• According to the World Meteorological Organization, an “ice shelf” is a:
• The layer of the atmosphere where jet streams are mainly found is the:
• The Swedish oceanographer Ekman deduced that surface currents diverge from the wind direction:
• The air of the Earth’s atmosphere is made up of various gases, the most abundant being nitrogen, oxygen, argon and carbon dioxide. Which takes up the largest share of the atmosphere?... :
• The atmospheric layer where most weather occurs and the air masses around the Earth interact is the:
• In a squall, two air masses (one cold and one warm) are in unstable equilibrium when, on meeting, the thermal reaction is such that... :
• In the Northern Hemisphere, in the dangerous front sector of a cyclone or hurricane... :
• The cold South Atlantic current that flows from the Cape of Good Hope up the South African coast as far as the waters of Namibia is known as:
• The layer of the Earth’s atmosphere that reflects radio waves of MF and HF (medium and short wave) is the:
• The most unstable part of the Earth’s atmosphere, where the phenomena that shape the weather occur, is called the:
• For a shower or storm to develop, it takes, among other things:
• Waterspouts form over bodies of sea water that are:
• In the North Atlantic, the trade winds run:
• The collision of warm air from the subtropical anticyclones with cold air from the polar anticyclones forms the:
• Hurricanes or tropical cyclones form in the areas between the parallels:
• In the Northern Hemisphere, if we are caught in the dangerous front semicircle of a cyclone or hurricane:
• The great North Atlantic current flowing from the Straits of Florida towards the coasts of Atlantic Europe, in a great arc across the Atlantic, warm at first and temperate later, is called the:
• The type of floating ice called pack ice is of:
• The imaginary belt around the Earth near the Equator, coinciding with the equatorial low pressure belt, is called:
• The layer of the atmosphere where the weather that matters to navigation occurs is:
• If, sailing from Cape Verde to the Caribbean (North Atlantic), we are caught by a hurricane and see the wind veering clockwise, we have been caught by:
• The strength of a cyclone or hurricane is measured by:
• If, in a storm area, St Elmo’s Fire appears on our yacht’s rigging, it could be the prelude to:
• The monsoon wind regime originates in:
• What are the main gases in the atmosphere and their approximate proportions?
• In the South Atlantic is the current called:
• In the northern hemisphere the trade winds blow:
• The Brazil Current (South Atlantic) runs:
• In the North Atlantic a current of temperate water runs from Florida and the east coast of the United States towards Europe. It is called:
• The characteristic wind regime of the Indian Ocean is…
• In waterspouts, the clouds associated with the phenomenon are...
• In floating sea ice, the approximate part showing above the water, out of its whole volume or mass, is…
• Signs (among others) of floating ice at sea are...
• In the Arctic zone north of Iceland, on a tourist cruise in a large adapted yacht, we see a calm sea, a whitish or yellowish sky and a sudden drop in temperature. These circumstances indicate...
• In South Atlantic waters, on the Atlantic coasts from South Africa to Namibia, the current affecting us is the Benguela, which is...
• The atmospheric optical phenomena of the parhelion and paraselene (seeing two suns or two moons) are due to...
• In fully formed hurricanes or cyclones, the typical clouds are...
• A hurricane moving through the tropical North Atlantic forms two semicircles. Which is the navigable semicircle?
• The layer of the Earth’s atmosphere where auroras occur and radio waves are reflected is called:
• Sailing near the Caribbean, a yacht is caught by a hurricane in its dangerous semicircle, in the forward quadrant. If the yacht does not manoeuvre, the sea and wind will:
• In the North Atlantic, the trade wind regime circulates...
• The intertropical convergence zone, or ITCZ, covers…
• The Earth’s atmosphere has a layer holding the breathable oxygen and the humidity from the seas, where atmospheric phenomena occur. It is called:
• In the Indian Ocean, sailing near the Maldives in cyclone season, we see abundant cirrus clouds. They indicate:
• A cold air mass meets a warm, humid air mass, creating a line of instability. This will produce:
• The waterspouts typical of the Mediterranean in early autumn go with clouds of the type:
• In South Atlantic waters, the Brazil Current is, in temperature:
• The Intertropical Convergence Zone (ITCZ), or Doldrums, lies:
• When speaking of the strength of a cyclone, the scale meant is the
• The contact zone between the warm air of the subtropical highs and the cold air of the polar highs forms:
• Weather (clouds, rain, winds, etc.) occurs in:
• At the centre or vortex of a cyclone or hurricane, there are:
• In the Atlantic and Pacific oceans, the winds running from the subtropical highs to the equatorial lows are called:
• The greatest chance of meeting an iceberg in the North Atlantic would be:
• The collision of the warm air of the subtropical highs with the cold air of the polar highs gives rise to:
• The glaciers of the Arctic and Antarctic land areas give rise to:
• Ice of marine origin forms on the sea surface and, once formed, is called:
• In July, sailing from Cape Verde to the Caribbean, we are caught by a hurricane in its navigable semicircle. Given the winds in this semicircle, the yacht:
• The Jet Stream phenomenon refers to:
• In what layer of the atmosphere are the radio waves used for communications reflected?
• How does the general circulation of currents in the North Atlantic work?
• What is the name of the weather phenomenon in which the electrical potential difference between pointed objects, such as a boat’s masts, and the cloud base causes discharges?
• The Coriolis effect makes a wind blowing from the south:
• Waterspouts are linked to clouds of the type...:
• On the origin of floating ice, the iceberg type originates...:
• The Gulf Stream runs across the North Atlantic:
• North Atlantic, sailing near the Caribbean, in June, a hurricane catches us in its dangerous forward sector. We will manoeuvre by:
• Monsoon winds occur in:
• The Benguela sea current (Southeast Atlantic) is, thermally:
• The prevailing Westerlies in the North Atlantic blow: