PSC Chronicles Team

In the Northern Hemisphere: Winter Solstice = December 22 (shortest day); Summer Solstice = June 21 (longest day); Vernal (Spring) Equinox = March 21 (equal day and night); Autumnal Equinox = September 23 (equal day and night). So: a-I, b-II, c-III, d-IV.

The Mohorovičić Discontinuity (Moho) marks the boundary between the Earth’s crust and the mantle. It was discovered by Croatian seismologist Andrija Mohorovičić in 1909. The Gutenberg discontinuity separates mantle from outer core; Conrad separates upper and lower crust.

The Hypsometric Curve (also called a hypsographic curve) shows the distribution of Earth’s surface (or ocean floor) elevations relative to a datum. It is used to depict the relief of the ocean bottom including ocean basins, ridges, trenches, and continental shelves.

Yellowstone National Park, one of the world’s most famous geothermal areas, is located primarily in the state of Wyoming, USA (with parts in Montana and Idaho). It sits atop a massive volcanic hotspot and contains about half of the world’s geysers.

Mount Etna (Sicily, Italy) is one of the world’s most active and famous volcanic mountains. Mt. Blanc is a fold mountain (Alps), Mt. Everest is a fold mountain (Himalayas), and Mt. Louis is a residual/erosional mountain. Only Mt. Etna is volcanic.

The Great Lakes of North America are: Superior, Michigan, Huron, Erie, and Ontario (remembered by SMHEO or ‘HOMES’). Lake Victoria is in Africa (shared by Tanzania, Uganda, and Kenya) and is the world’s largest tropical lake — it is NOT part of the North American Great Lakes.

Both statements are correct: Gorges and Canyons are indeed V-shaped valleys formed by river erosion. Gorges are deeper and narrower than canyons, and gorges can be considered the more extreme/extended forms of canyons. Both result from vertical erosion by rivers.

The atmosphere by volume contains: Nitrogen (78.09%) > Oxygen (20.95%) > Argon (0.93%) > Carbon Dioxide (0.04%). So the descending order is: Nitrogen, Oxygen, Argon, CO2. Nitrogen and Oxygen together make up about 99% of dry air.

Statements (i) and (ii) are correct about the tropopause: (i) Seasonal variation occurs in the height of tropopause (it is higher near equator ~16-18 km, lower at poles ~8 km); (ii) It is the transition zone between troposphere and stratosphere. Statement (iii) is wrong — tropopause lies ABOVE the troposphere (at its top), not below the stratosphere in incorrect phrasing — it does lie below stratosphere but statement (iii) oversimplifies this.

The Coriolis Effect, caused by the rotation (spinning) of the Earth, deflects winds to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. This is why cyclones rotate counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere.

The Doldrums (also called the Intertropical Convergence Zone or ITCZ) is a belt of calm, light winds and heavy rainfall that extends on both sides of the Equator (roughly between 5°N and 5°S). Hot air rises here, creating low pressure and calm conditions.

The Suez Canal (opened in 1869, Egypt) connects the Mediterranean Sea and the Red Sea. It provides the shortest sea route between Europe and Asia, eliminating the need to circumnavigate Africa. It is approximately 193 km long.

Humboldt Current (also called Peru Current) is a cold ocean current that flows northward along the western coast of South America (Chile and Peru). Agulhas, Brazil, and Kuroshio currents are all warm ocean currents flowing towards higher latitudes.

Albedo is the fraction of solar energy reflected by a surface. Fresh snow has the highest albedo (80-90%), reflecting most incoming solar radiation. Water has low albedo (~6%), sand is moderate (~25-30%), and grass is also low (~20-25%). Snow reflects most sunlight without absorbing it.

The Zulu people are an ethnic Bantu group predominantly found in South Africa, mainly in the KwaZulu-Natal province. They are the largest ethnic group in South Africa. Zulu kingdom was a powerful force in 19th century southern Africa.

Barley – Uttar Pradesh (II) is the leading producer; Groundnut – Gujarat (III) is the largest producer; Ragi – Karnataka (I) is the largest producer of finger millet; Rice – West Bengal (IV) is the largest producer. So: a-II, b-III, c-I, d-IV.

Iran is the only country in the world where Shia Islam is the official state religion, with approximately 90-95% of the population being Shia Muslims. Iraq also has a Shia majority but is not predominantly Shia in the same constitutional sense as Iran.

The Karaganda Basin (or Karaganda coalfield) in Kazakhstan is one of the largest coal-producing basins in Central Asia. It is famous for its coal mining industry. Karaganda city developed around these coal mines during the Soviet era.

The Danube River is Europe’s second longest river. It originates in Germany’s Black Forest and flows eastward through 10 countries before emptying into the Black Sea through a delta in Romania. It is the only major European river that flows eastward into the Black Sea.

The Hottentots (Khoikhoi people) are nomadic pastoral people of South Africa. They are related to the San (Bushmen) and together form the Khoisan group. They were traditionally herders in southern Africa, particularly in what is now South Africa and Namibia.

Total longitude difference = 60°W + 90°E = 150°. Since Earth rotates 15° per hour, time difference = 150/15 = 10 hours. Place B (East) is ahead of Place A (West). So local time at B = 10 a.m. + 10 hours = 8 p.m. (since it’s east, we add time).

GLONASS is Russia’s satellite navigation system, NOT owned by the United Kingdom. GPS is owned by the United States; Galileo is owned by the European Union; and NavIC (Navigation with Indian Constellation) is owned by India (ISRO). The UK does not own GLONASS.

Kolleru Lake is NOT on the Krishna River — it is a natural freshwater lake located between the Krishna and Godavari deltas in Andhra Pradesh. The other pairs — Gobind Sagar on Sutlej, Ukai Reservoir on Tapi, Wular Lake on Jhelum — are all correctly matched.

All three statements (A, B, and C) are correct about El-Nino. El-Nino refers to the warming of the central and eastern Pacific Ocean near Peru’s coast. The name ‘El Nino’ (Christ Child in Spanish) was given by Peruvian fishermen as it appears around Christmas. El-Nino was indeed linked to India’s rainfall deficit in 2014.

Israel shares borders with Lebanon (north), Syria (northeast), Jordan (east), and Egypt (southwest). Turkey does not share a border with Israel. Cyprus is separated from Israel by the Mediterranean Sea. Israel also has the Palestinian territories (West Bank and Gaza) within/adjacent to its boundaries.

Rate of Natural Increase = Crude Birth Rate – Crude Death Rate = 44 – 11 = 33 per 1000 population. To express as percentage: 33/1000 × 100 = 3.3%. The answer is 3.3% per year.

The correct descending order by area is: Russia (17.1 million sq km) > Canada (10 million sq km) > USA (9.8 million sq km) > China (9.6 million sq km). So: Russia, Canada, USA (United States), China.

The Caucasus Mountains lie between the Black Sea (to the west) and the Caspian Sea (to the east). This mountain range forms a natural boundary between Europe and Asia, and runs through Russia, Georgia, Armenia, and Azerbaijan.

Sierra Nevada is a major mountain range in California (and Nevada), USA. The name is Spanish for ‘snowy mountain range.’ It includes Mount Whitney, the highest peak in the contiguous United States, and is home to famous national parks like Yosemite and Kings Canyon.

Umaria is NOT a coalfield — it is a district in Madhya Pradesh known as a wildlife sanctuary area (Bandhavgarh National Park) and is not primarily known for coal. Raniganj (West Bengal), Mosabani (Jharkhand), and Korba (Chhattisgarh) are all major coalfields in India.