Geography · Environmental Studies

Oceanography and Hydrology

1,673 Questions

Find relevant questions on oceanography and hydrology that address aquatic ecosystems and physical geography. The topics include coastal landforms, coral reefs, ocean salinity, and tidal patterns. These concepts frequently appear in civil services and state level administrative examinations.

Coral reef structuresCoastal landformsOcean salinity patternsGlacial retreat impactsMangrove ecosystems

Oceanography and Hydrology Questions

Multiple choice

Fishing groups are concentrated in the high latitudes the reasons are

  1. great length of indented coastline
  2. extensive continental coastline
  3. water temperature lower than 20o C
  4. sparse population

  1. 2, 3 and 4

  2. 1 and 2

  3. 2 and 4

  4. 1, 2 and 3
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

High-latitude fishing grounds (like the North Atlantic) have extensive continental shelves (reason 2), indented coastlines (reason 1), and cold water below 20°C (reason 3). Sparse population is irrelevant - fishing depends on ocean conditions, not human settlement patterns.

Multiple choice

Red tide is caused by

  1. protozoans

  2. corals

  3. dinoflagellates

  4. All of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Red tide is caused by dinoflagellates (like Karenia brevis), which are microscopic algae that can reproduce rapidly and produce harmful toxins that color the water red. They are neither protozoans, corals, nor all of the above.

Multiple choice

Mean sea level means

  1. the average depth of the sea-level in the pacific ocean

  2. the mean of the sea level in the pacific ocean

  3. the average level of the sea

  4. none of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Mean sea level is the average surface level of the ocean, calculated from tidal observations over a long period. It serves as the reference point (zero elevation) for measuring altitude and depth on Earth. Options A and B incorrectly specify the Pacific Ocean, which would be a regional measure, not the global standard.

Multiple choice

Which of the following statements is incorrect?

  1. Iron-rich dust influx from large desert can cause red tides.

  2. Coastal water pollution can cause red tides.

  3. The occurrence of red tides may be natural or from human activities.

  4. When the algae are present in high concentrations, the water appears to be discolored.

  5. Red tides are related to the movements of the tides.
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Red tides are unrelated to movements of the tides.They are not necessarily red and many have no discoloration at all.

Multiple choice

Which of the following statements is/are incorrect?

a. Steep waves are fairly young ones and are formed by local wind. b. Slow and steady waves originate from far away places. c. The maximum wave height is determined by the gravitational pull.

  1. only a

  2. only b

  3. only c

  4. only a and b

  5. a, b and c
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This is the correct answer choice as this statement is incorrect. The maximum wave height is determined by the strength of the wind, i.e. how long it blows and the area over which it blows in a single direction.

Multiple choice

Surges are

  1. the periodical rise and fall of the sea level, once or twice a day

  2. the major cause for the occurrence of tides

  3. created on opposite sides of Earth due to the moon's gravitational force and centrifugal force

  4. the tides that are channeled between islands or into bays and estuaries

  5. the various movements of water caused by meteorological effects
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

This is the correct answer. 

Multiple choice

Which of the following statements is/are correct about waves?

a. Waves grow larger as they move and absorb energy from the wind. b. Waves slow down at the beach due to friction occurring between dynamic water and sea floor. c. Waves break when the depth of water is less than the wavelength of the wave.

  1. Only a

  2. Only b

  3. Only c

  4. Both a and b

  5. Both b and c
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This is the correct answer as both statements are correct.

Multiple choice

Choose the incorrect statement.

  1. The tidal bulges on wide continental shelves have greater height.

  2. When tidal bulges hit the mid-oceanic islands, they become low.

  3. The shape of bays and estuaries along a coastline can reduce the intensity of tides.

  4. Funnel-shaped bays greatly change tidal magnitudes.

  5. Surges are not regular like tides.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This is an incorrect statement. 

Multiple choice

Which of the following statements is/are correct?

a. Sometimes, the height of high tide varies depending upon the position of sun and moon with respect to Earth. b. The time between the high tide and low tide, when the water level is falling, is called ebb. c. The time between the low tide and high tide, when the tide is rising, is called flow or flood.

  1. a only

  2. b only

  3. c only

  4. a and c

  5. a, b and c
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

This is the correct answer.

Multiple choice

Which of the following statements is incorrect about ocean currents?

  1. They represent a regular volume of water in a definite path and direction.

  2. Coriolis force causes the water to move to the left in the northern hemisphere and to the right in the southern hemisphere.

  3. Cold water ocean currents occur when the cold water at the poles sinks and slowly moves towards the equator.

  4. Gyres produce large circular currents in all the ocean basins.

  5. Speed of current is measured by its drift.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

This is incorrect.