Which of the following have a major impact on Indian Monsoon?

(1) ENSO (El-Nino Southern Oscillation)

(2) Indian Ocean Dipole

(3) Sub-tropical Westerly Jet Stream

(4) Canary Current

Select the correct answer using the code given below:

(a) 1, 2 and 3 only

(b) 1, 3 and 4 only

(c) 2, 3 and 4 only

(d) 1, 2, 3 and 4

Ans: (a) Explanation: ENSO, IOD and Sub-tropical Westerly Jet Stream are known to have a major impact on the Indian Monsoon. The El Niño-Southern Oscillation (ENSO) is a recurring climate pattern involving changes in the temperature of waters in the central and eastern tropical Pacific Ocean. On periods ranging from about three to seven years, the surface waters across a large swath of the tropical Pacific Ocean warm or cool by anywhere from 1°C to 3°C, compared to normal. This oscillating warming and cooling pattern, referred to as the ENSO cycle, directly affects rainfall distribution in the tropics. ENSO results in weakening of Indian Monsoon, ‘breaks’ in monsoon and resultant droughts in an El-Nino year. Indian Ocean Dipole (IOD) : The Indian summer monsoon rainfall is influenced by a system of oscillating sea surface temperatures known as the Indian Ocean Dipole (IOD) in which the western Indian Ocean becomes alternately warmer and then colder than the eastern part of the ocean. A positive IOD occurs when the sea surface temperatures are greater than normal in the Arabian Sea and less than normal in the tropical eastern Indian Ocean. When the reverse is the case, a negative IOD is said to have developed. A positive IOD leads to greater monsoon rainfall and more active (above normal rainfall) monsoon days while negative IOD leads to less rainfall and more monsoon break days (no rainfall). Sub-tropical Westerly Jet Stream, moves in north/south of Himalayas depending on time of the year (North in Summer and South in Winters) which is theorized to be the trigger to the monsoon. Canary Current flows off the Western Coast of Africa, near Canary Island, and has no influence on Monsoon.

Source: NCERT, India: Physical Environment, Chapter 4 Page – 38.

2. Consider the following:

(1) Nilgiri Biosphere Reserve

(2) Nokrek Biosphere Reserve

(3) Panna Biosphere Reserve

(4) Simlipal Biosphere Reserve

Which of the above is/are not a part of the ‘World Network of Biosphere Reserves of UNESCO’?

(a) 1 only

(b) 3 only

(c) 4 only

(d) 2 and 3 only

Ans: (b) Explanation:

A biosphere reserve is an ecosystem with plants and animals of unusual scientific and natural interest. It is a label given by UNESCO to help protect the sites. The plan is to promote management, research and education in ecosystem conservation. This includes the 'sustainable use of natural resources'. World Network of Biosphere Reserves (WNBR) is composed of 686 biosphere reserves in 122 countries, including 20 trans-boundary sites. WNBR promotes North- South and South-South collaboration and represents a unique tool for international co- operation through sharing knowledge, exchanging experiences, building capacity and promoting best practices. Nilgiri Biosphere Reserve is a part of Western Ghats which was declared World Heritage site by UNESCO in 2012. Nokrek Biosphere Reserve, a national park in Garo hills of Meghalaya was added by UNESCO in 2009. Simplipal is a national park and tiger reserve located in Odisha and was added to UNESCO’s list in 2009.

Source: Physical Environment NCERT Class XI- Page no 64.

3. Match List-I with List-II and select the correct answer using the code given below:

List-I List-II

Forest : Fauna

A. Mangrove forests : 1. Tortoises

B. Tropical Deciduous Forests : 2. Horned Rhinoceros

C. Montane Forest : 3. Royal Bengal Tiger

D. Tropical Evergreen Forest : 4. Tibetan Antelope

Codes

A B C D

(a) 1 2 3 4

(b) 3 1 4 2

(c) 3 2 4 1

(d) 3 2 1 4

Ans: (b) Explanation: Royal Bengal Tigers are found in mangrove forests like deltas of Ganga, Mahanadi, Krishna and Godavari. India is the only country in the world that has both tigers and lions. Tortoises are found in tropical deciduous forest. In these forests, the common animals found are lion, tiger, pig, deer and elephant. Tibetan Antelope is found in Montane forests. The exceptionally fine underfur of the Tibetan antelope or chiru insulates it against the harsh climate of the Tibetan plateau.

Unfortunately, this fur, known as shahtoosh, also makes the chiru a target for illegal hunters. Horned rhinoceros are found in tropical evergreen forests. The greater one-horned rhino (or “Indian rhino”) is the largest of the rhino species. Once widespread across the entire northern part of the Indian sub- continent, rhino populations plummeted as they were hunted for sport or killed as agricultural pests. This pushed the species very close to extinction and by the end of the 20th century, fewer than 200 animals remained. The recovery of the greater one-horned rhino is among the greatest conservation success stories in Asia. Due to strict protection and management from Indian and Nepalese wildlife authorities, the greater one-horned rhino was brought back from the brink.

Source: Contemporary India, NCERT Class IX-Page no 46-47.

4. Which of the following factors influence the formation of Meanders?

(1) Very gentle gradient

(2) Unconsolidated nature of alluvial deposits

(3) Coriolis Force

Select the correct answer using the code given below:

(a) 1 and 2 only

(b) 1 and 3 only

(c) 2 and 3 only

(d) 1, 2 and 3

Ans: (d) Explanation: Meander is a type of depositional landform formed by rivers. It is a channel pattern created because of water flowing over very gentle slopes along with unconsolidated alluvial deposits. The Coriolis force acts on the water and deflects it like wind. They are typical of the middle and lower course of a river. This is because vertical erosion is replaced by a sideways form of erosion called LATERAL erosion, plus deposition within the floodplain. When the loops get too large and consume too much energy (friction), the river will eventually find a less energetically "taxing" shortcut, and a part of the old channel will be abandoned and becomes an oxbow lake.

Source: NCERT Class 11, chapter 7, page 63.

5. Which of the following are the depositional landforms by various geomorphic agents?

(1) Potholes

(2) Sand dunes

(3) Pedestal rocks

(4) Spits

(5) Terraces

(6) Eskers

Select the correct answer using the code given below:

(a) 1, 2 and 6 only

(b) 2, 4 and 6 only

(c) 3, 4 and 5 only

(d) 2, 3 and 4 only

Ans: (b) Explanation: Many different types of landforms make up Earth’s topography. Several major categories of landform define that smaller portion of the planet not covered by water, including mountains, plains, plateaus and valleys. These can be formed by a variety of natural forces, including erosion from water and wind, plate movement, folding and faulting, and volcanic activity. Running water, groundwater, glaciers, the wind, waves, and currents, etc., can be called geomorphic agents that play role in formation of various landforms Potholes are the erosional landforms formed by running water; they are circular depressions. Sand dunes, spits and eskers are depositional landforms formed by winds, waves and glaciers respectively. Pedestal rocks are erosional landforms by winds. Terraces are formed by wave’s erosional features.

Source: NCERT Class 11, chapter 7