hydrosphere & oceanography section 1 MCQ Questions & Answers Detailed Explanation

Answer: (b)

Answer: (c)

Answer: (d)

Normal El Nino forms in south–eastern Pacific whereas as El Nino Modoki forms in central Pacific and causes greater number of hurricanes.

Answer: (b)

Tide-generating forces (TGF) are a result of the gravitational attraction between the earth, the sun, and the moon and the centrifugal force due to the relative motions of the moon around the earth, and the earth around the sun.

While these forces exactly balance on average, the local mismatch at the earth's surface creates a horizontal force directed towards the surface points closest and farthest from the moon.

Answer: (b)

The Great Barrier Reef is located on the coast of East Australia. The Great Barrier Reef is the world’s largest coral reef system composed of over 2,900 individual reefs and 900 islands stretching for over 2,600 kilometres over an area of approximately 344,400 square kilometres.

Answer: (d)

Tsunamis have a small amplitude (wave height) offshore, and a very long wavelength (often hundreds of kilometres long, whereas normal ocean waves have a wavelength of only 30 or 40 metres), which is why they generally pass unnoticed at sea, forming only a slight swell usually about 300 millimetres above the normal sea surface. They grow in height when they reach shallower water or the coast.