Coast Guard Test Maritime Weather and Oceanography 1 — Questions and Answers
Question 1: What does the Beaufort scale measure?
- Water temperature
- Wind speed at sea (Correct answer)
- Ocean wave height
- Barometric pressure
Correct answer: Wind speed at sea
The Beaufort scale is an empirical measure that rates wind speed based on observed sea and land conditions, ranging from 0 (calm) to 12 (hurricane-force).
Question 2: What type of fog is most commonly encountered in coastal waters when warm, moist air moves over a colder sea surface?
- Radiation fog
- Advection fog (Correct answer)
- Upslope fog
- Frontal fog
Correct answer: Advection fog
Advection fog forms when warm, moist air moves horizontally over a cooler ocean surface, cooling the air to its dew point and forming fog.
Question 3: A rapidly falling barometer aboard a vessel most likely indicates:
- Clear and calm weather ahead
- Approaching storm or severe weather (Correct answer)
- Stable sea conditions
- Improving visibility
Correct answer: Approaching storm or severe weather
A rapid drop in barometric pressure signals an approaching low-pressure system, which brings deteriorating weather, strong winds, and rough seas.
Question 4: In the Northern Hemisphere, winds around a low-pressure system rotate in which direction?
- Clockwise
- Counterclockwise (Correct answer)
- Outward from the center
- Toward the east
Correct answer: Counterclockwise
In the Northern Hemisphere, the Coriolis effect causes winds around a low-pressure center to rotate counterclockwise (cyclonically).
Question 5: Significant wave height is defined as the average height of the:
- Tallest 10% of waves
- Tallest third of waves (Correct answer)
- All waves observed
- Smallest 50% of waves
Correct answer: Tallest third of waves
Significant wave height is the mean height of the highest one-third of waves, which correlates closely with what an experienced observer would estimate visually.
Question 6: What does the acronym NAVTEX stand for?
- Naval Text Exchange
- Navigational Telex (Correct answer)
- National Weather Transmission
- Navigational Alert System
Correct answer: Navigational Telex
NAVTEX (Navigational Telex) is an international automated direct-printing service that broadcasts maritime safety information including weather warnings and navigational notices.
Question 7: A vessel's barometer reads 29.53 inches Hg and is steady. This indicates:
- An approaching cold front
- Fair, stable weather conditions (Correct answer)
- An imminent storm
- Tropical cyclone development
Correct answer: Fair, stable weather conditions
A steady barometer near 29.53 inches Hg (1000 mb) combined with a stable reading suggests settled, fair weather with no immediate weather changes expected.
Coast Guard Test Maritime Weather and Oceanography 1
What does the Beaufort scale measure?