Every question from this NCERT chapter, with a detailed explanation.
What is the primary reason for the absence or weakening of the thermocline layer in mid-latitudes during the winter season?
Consider the following statements regarding the Hudson Canyon: 1. It is a prominent mid-oceanic ridge. 2. It is located in the Atlantic Ocean. 3. It extends from the mouth of a large river. Which of the statements given above is/are correct?
With reference to the hydrological cycle, consider the following statements: 1. It involves the continuous exchange of water between the atmosphere, land surface, subsurface, and organisms. 2. About 30 % of the planetary water is found in the oceans. 3. The renewable water on the earth remains constant over time while the demand is decreasing. Which of the statements given above is/are correct?
Consider the following statements regarding the relief of the ocean floor: 1. The oceans merge so naturally into one another that it is hard to demarcate them. 2. A major portion of the ocean floor is found at depths less than 1 km. 3. The ocean floors are rugged and contain mountain ranges similar to those on continents. Which of the statements given above is/are correct?
Which one of the following sequences correctly arranges the major divisions of the ocean floor from the coast towards the deep sea?
With reference to the Continental Shelf, consider the following statements: 1. It is the deepest part of the ocean showing an average gradient of 5°. 2. The shelf typically ends at a very steep slope called the shelf break. 3. The width of continental shelves varies significantly from one ocean to another. Which of the statements given above is/are correct?
Which of the following regions is known for having the largest continental shelf in the world?
Consider the following statements regarding the Continental Slope: 1. It connects the continental rise and the mid-oceanic ridges. 2. The gradient of the slope region varies between 2° and 5°. 3. Canyons and trenches are never observed in this region. Which of the statements given above is/are correct?
With reference to Oceanic Deeps or Trenches, consider the following statements: 1. They are the deepest parts of the oceans, located 3-5 km deeper than the surrounding floor. 2. They are tectonically stable regions with no volcanic activity. 3. The Pacific Ocean has the highest number of explored trenches compared to the Atlantic Ocean. Which of the statements given above is/are correct?
The Emperor seamount, an extension of the Hawaiian Islands in the Pacific Ocean, is a good example of which relief feature?
Consider the following statements regarding Atolls: 1. They are high mountainous islands found in polar oceans. 2. They consist of coral reefs surrounding a central depression. 3. The central depression may get filled with sea water to form a lagoon. Which of the statements given above is/are correct?
Which of the following factors affect the distribution of temperature of ocean water? 1. Latitude 2. Unequal distribution of land and water 3. Prevailing wind 4. Ocean currents Select the correct answer using the code given below:
With reference to the influence of winds on ocean temperature, consider the following statements: 1. Winds blowing from the land towards the oceans drive warm surface water away from the coast. 2. The removal of surface water by offshore winds results in the sinking of warm water. 3. Onshore winds drive warm water away from the coast, lowering the temperature. Which of the statements given above are correct?
In comparison to open oceans, enclosed seas in low latitudes typically exhibit:
Consider the following statements regarding the vertical distribution of ocean temperature: 1. The temperature-depth profile shows a boundary region called the thermocline where temperature decreases rapidly. 2. About 90 % of the total volume of water is found above the thermocline. 3. In the Arctic and Antarctic circles, the surface water temperatures are close to 0°C, resulting in very slight temperature change with depth. Which of the statements given above is/are correct?
Consider the following statements regarding the spatial pattern of surface temperature of oceans: 1. The highest temperature of the oceans is recorded exactly at the equator. 2. The oceans in the northern hemisphere record relatively higher temperatures than in the southern hemisphere. 3. The rate of decrease of temperature with increasing latitude is generally 0.5°C per latitude. Which of the statements given above is/are correct?
What is the primary reason for the variation in average annual temperatures between the northern (19°C) and southern (16°C) hemispheres?
Which salinity value is conventionally considered the upper limit for demarcating 'brackish water'?
Consider the following factors affecting ocean salinity: 1. Evaporation and precipitation 2. Fresh water flow from rivers 3. Freezing and thawing of ice 4. Atmospheric pressure Which of the factors given above are explicitly mentioned in the text?
Which one of the following water bodies has the highest salinity?
With reference to the horizontal distribution of salinity, consider the following statements: 1. The salinity for normal open ocean ranges between 10 ppt and 15 ppt. 2. In the Red Sea, salinity is as high as 41 ppt. 3. In estuaries, salinity remains constant at 35 ppt throughout the year. Which of the statements given above is/are correct?
Which factor primarily accounts for the relatively higher salinity recorded in the North Sea despite its high-latitude location?
Consider the following pairs regarding salinity trends in different seas: 1. Baltic Sea : Low salinity due to river influx 2. Mediterranean Sea : High salinity due to high evaporation 3. Black Sea : Very low salinity due to fresh water influx 4. Bay of Bengal : High salinity due to low fresh water influx How many of the above pairs are correctly matched?
With reference to the vertical distribution of salinity, consider the following statements: 1. Salinity at the surface is increased by the loss of water to ice or evaporation. 2. Salinity at depth is highly variable because salt is frequently added or lost. 3. There is a distinct zone called the halocline where salinity increases sharply. Which of the statements given above is/are correct?
How does increasing salinity affect the density of seawater, assuming other factors remain constant?
Which of the following is NOT a division of the ocean floor?
Consider the following statements regarding the distribution of planetary water: 1. The remainder of the water is permanently lost to space. 2. Nearly 59 % of the water that falls on land returns to the atmosphere through evaporation. 3. Glaciers and icecaps hold a larger percentage of water than the oceans. Which of the statements given above is/are correct?
Which relief feature of the ocean floor is described as "flat topped seamount"?
Mid-Oceanic Ridges are characterized by: 1. Two chains of mountains separated by a large depression. 2. The peaks of these ridges never reach the ocean's surface. 3. They are found in all the major oceans of the world. Which of the statements given above is/are correct?
What is the average temperature of ocean surface water at 40° latitudes?
Which of the following is an example of a Mid-Oceanic Ridge peak reaching above the surface?
Consider the following statements about Seamounts: 1. They are formed exclusively by sedimentary deposits. 2. They can be 3,000-4,500 m tall. 3. They do not reach the surface of the ocean. Which of the statements given above is/are correct?
In comparison to landmasses, the process of heating and cooling of oceanic water is:
Which layer of the ocean temperature profile is characterized by temperatures approaching 0°C?
Consider the following statements regarding the salinity of the Atlantic Ocean: 1. The highest salinity is recorded at the equator. 2. The average salinity is around 36 ppt. 3. Maximum salinity is observed in the polar regions. Which of the statements given above is/are correct?
Which of the following statements is NOT correct regarding the Continental Shelf?
The "shelf break" typically occurs at the end of which ocean relief feature?
Consider the following statements about Submarine Canyons: 1. They are deep valleys comparable to the Grand Canyon. 2. They are found exclusively in the deep sea plains. 3. They can be formed by turbidity currents. Which of the statements given above is/are correct?
Which ocean has the highest number of explored deeps or trenches?
With reference to the temperature of ocean water, consider the following: 1. The average temperature of surface water is about 10°C. 2. The temperature gradually decreases from the equator towards the poles. 3. The rate of decrease of temperature with latitude is generally 0.5°C per latitude. Which of the statements given above is/are correct?
Consider the following statements regarding the density of ocean water: 1. Increasing salinity causes density to decrease. 2. High salinity seawater generally sinks below lower salinity water. 3. Stratification by salinity is never observed in oceans. Which of the statements given above is/are correct?
In which region is the continental shelf almost absent or very narrow?
Which of the following statements about the "Oceanic Deeps" is correct?
Consider the following statements regarding the salinity in the Indian Ocean: 1. The average salinity is 35 ppt. 2. The Bay of Bengal shows higher salinity than the Arabian Sea. 3. The Arabian Sea has high evaporation and low fresh water influx. Which of the statements given above is/are correct?
Which factor is responsible for the longitudinal variation in temperature of ocean water?
The "Halocline" is a distinct zone in the ocean where:
What is the typical gradient range of the Continental Slope?
Consider the following statements regarding the temperature of enclosed seas: 1. Enclosed seas in low latitudes record lower temperatures than open seas. 2. Enclosed seas in high latitudes record lower temperatures than open seas. Which of the statements given above is/are correct?
The "Second Layer" in the three-layer temperature system of the ocean is also known as:
Which of the following statements about the "Continental Shelf" width is correct?
Consider the following statements regarding the "Mid-Atlantic Ridge": 1. It is an example of a deep sea trench. 2. Iceland is a part of this ridge. 3. Portions of it rise above the sea level. Which of the statements given above is/are correct?
The average salinity of the Indian Ocean is:
Consider the following statements regarding the "Deep Sea Plain" depth: 1. It lies between 3,000 and 6,000 meters. 2. It is shallower than the Continental Slope. 3. It is the deepest part of the ocean. Which of the statements given above is/are correct?