Test: Water - UPSC MCQ

The Gulf Stream is a warm ocean current. Here are some key points:

• It originates in the Gulf of Mexico.
• Flows along the eastern coast of the United States.
• Helps moderate the climate of nearby regions by transporting warm water.

The average salinity of the ocean is approximately 35 parts per thousand (ppt). This means there are about 35 grams of dissolved salts in every kilogram of seawater.

This value can vary slightly depending on factors such as:

• Location
• Environmental conditions

However, 35 ppt is widely accepted as the global average for ocean water salinity.

The Labrador Current is known as a cold ocean current. Here are some important points about it:

• It flows southward along the coast of Canada and into the North Atlantic Ocean.
• The cold waters significantly influence the climate of the regions it passes.
• This current plays a crucial role in the marine ecosystem by supporting diverse marine life.

Oceans contain approximately 97.3% of Earth's total water. This water is predominantly saline, meaning it contains dissolved salts, which distinguishes it from freshwater sources.

While oceans cover about 70% of the Earth's surface, they hold a much larger proportion of its water due to their:

• Depth
• Volume

The Dead Sea is renowned for having the highest salinity among the given options, with a salt concentration of approximately 33.7%. This extreme salinity significantly increases the water's density, allowing individuals to float effortlessly on its surface due to the buoyant force exerted by the dense water.

Clouds form through the process of condensation, which involves the following steps:

• Water vapor in the atmosphere cools.
• This cooled water vapor transforms into tiny droplets or ice crystals.
• The accumulation of these droplets or crystals creates visible clouds.

The primary source of fresh water is underground reservoirs, which hold a significant portion of the Earth's freshwater in the form of groundwater. While visible sources such as rivers, ponds, springs, and glaciers exist, they constitute only a small fraction compared to what lies beneath the surface.

• Underground reservoirs are crucial for freshwater supply.
• They contain a significant amount of groundwater.
• Visible sources of freshwater include:
  • Rivers
  • Ponds
  • Springs
  • Glaciers
• These visible sources represent only a small fraction of total freshwater.