Consider the following statements: 1. The Red Sea receives very little precipitation in any form. 2. No water enters the Red Sea from rivers. Which of the statements given above is/are correct?

Updated 11 Apr 2026 · From UPSC Prelims GS Paper I 2024, Q23

Contents16
UPSC Prelims GS2024Geography
  1. A1 only
  2. B2 only
  3. CBoth 1 and 2
  4. DNeither 1 nor 2
Show answer

Answer: (C) Both 1 and 2

Correct Answer: C (Both 1 and 2)

1. The Red Sea receives very little precipitation in any form (Correct)

  • The Reason: The Red Sea is locked between northeastern Africa and the Arabian Peninsula. Its entire coastline runs through intense, arid desert regions.
  • The Reality: The area receives less than 250 mm of rainfall per year. Combined with scorching summer temperatures, it suffers from massive evaporation rates, making it one of the saltiest bodies of water on Earth.

2. No water enters the Red Sea from rivers (Correct)

  • The Reason: Because it is completely hemmed in by hyper-arid deserts, there is not a single major, permanent river or stream that flows into the Red Sea.
  • The Reality: Instead of fresh river water, it relies entirely on water exchange with the Mediterranean Sea to the north (via the Suez Canal) and the Indian Ocean to the south (via the Bab-el-Mandeb strait).

Simple Summary

  • Statement 1: It lies entirely in a desert zone, so it barely gets any rain. (True)
  • Statement 2: Not a single permanent river drains into it. (True)
  • The Result: High evaporation + No rivers + Low rain = An extremely warm and salty sea.
Why this was asked

The Red Sea has high salinity (about 39 ppt versus global average of 35.2 ppt) due to high evaporation and minimal freshwater input.

UPSC uses the absolute word 'no' in Statement 2 as a trap - small seasonal streams do enter the Red Sea, making the statement incorrect despite no major rivers flowing into it.

Red Sea Geography

Geography Red Sea precipitation rivers

Red Sea: Location, Climate & Water Sources

Must know

Red Sea is a narrow water body between Africa and Arabian Peninsula

Receives very little precipitation due to arid climate

Small seasonal streams enter the Red Sea, not major rivers

Good to know

High salinity of ~39 ppt due to evaporation exceeding freshwater input

Location & Climate

The Red Sea lies between northeastern Africa and the Arabian Peninsula, connected to the Indian Ocean through the Gulf of Aden. The region experiences an arid desert climate with extremely low rainfall throughout the year.

Water Sources Comparison

Water Source

Red Sea

Arabian Sea

Mediterranean Sea

Major Rivers

None

Indus River

Nile, Po, Rhône

Small Streams

Seasonal rivulets

Coastal streams

Various tributaries

Precipitation

Very low

Moderate (monsoon)

Mediterranean pattern

Salinity (ppt)

~39

~36

~38

Red Sea Location

Red Sea's location between two arid landmasses explains its minimal freshwater input
Red Sea's location between two arid landmasses explains its minimal freshwater input

Source: Britannica — Gulf of Aden | Map, Africa, & Facts | Britannica · www.britannica.com

Geographic Features

Length: Approximately 2,250 km from Gulf of Suez to Gulf of Aden

Width: Ranges from 200-300 km at widest points

Depth: Maximum depth exceeds 2,200 meters

Strategic importance: Connects Mediterranean (via Suez Canal) to Indian Ocean

Coral reefs: Extensive reef systems along both coasts

Question Analysis

This question tests understanding of Red Sea's water balance. Statement 1 correctly identifies the arid climate. Statement 2 uses the absolute word 'no water' which makes it incorrect - small seasonal streams do contribute some freshwater.

Exam traps

Absolute words trap: 'No water enters from rivers' - watch for 'no', 'never', 'all', 'only' in statements

Salinity confusion: High salinity doesn't mean zero freshwater input - it means evaporation exceeds input

River vs stream: Distinguish between major rivers (absent) and small seasonal streams (present)

Climate assumption: Don't assume all seas receive significant precipitation - Red Sea region is arid

Ocean Salinity Factors

Geography salinity

Ocean Salinity: Factors & Global Variations

Must know

Global average salinity is 35.2 parts per thousand (ppt)

Evaporation > Precipitation + River input leads to higher salinity

Good to know

Red Sea salinity (~39 ppt) is above global average

Dead Sea has highest salinity (~300 ppt) among major water bodies

Salinity Basics

Salinity measures dissolved salts in seawater, expressed in parts per thousand (ppt). It depends on the balance between water loss (evaporation) and water gain (precipitation, rivers, melting ice).

Salinity Determination Process

%%{init: {"flowchart": {"wrappingWidth": 460}}}%%
flowchart TD
  s1["`**High Evaporation**
Hot, dry climate removes water, concentrates salts`"]
  s2["`**Low Precipitation**
Limited rainfall means less dilution of seawater`"]
  s3["`**Minimal River Input**
Few rivers means less freshwater to dilute salts`"]
  s4["`**High Salinity**
Result: salt concentration above global average`"]
  s1 --> s2
  s2 --> s3
  s3 --> s4

Global Salinity Variations

Water Body

Salinity (ppt)

Key Factors

Dead Sea

~300

Enclosed, extreme evaporation, no outlet

Red Sea

~39

Arid climate, minimal rivers, high evaporation

Mediterranean

~38

High evaporation, limited river input

Arabian Sea

~36

Global average, balanced water cycle

Bay of Bengal

~32-34

Major rivers (Ganges, Brahmaputra), monsoon

Baltic Sea

~7-8

Many rivers, low evaporation, enclosed

Factors Affecting Salinity

Evaporation: Hot, dry climates increase salt concentration

Precipitation: Heavy rainfall dilutes seawater salinity

River discharge: Major rivers significantly reduce coastal salinity

Ocean currents: Mix waters of different salinity levels

Ice formation/melting: Sea ice formation increases salinity, melting decreases it

Exam traps

Number confusion: Global average is 35.2 ppt, not 35 or 36 ppt

Cause-effect reversal: High salinity is result of low freshwater input, not the cause

Absolute statements: Even high-salinity seas receive some freshwater - avoid 'zero' or 'no' inputs

Regional variations: Same sea can have different salinity levels - Bay of Bengal varies from 32-34 ppt

Major Marginal Seas

Geography

Major Marginal Seas: Characteristics & Comparisons

Must know

Marginal seas are partially enclosed by land, connected to main oceans

Red Sea, Arabian Sea, Mediterranean are key marginal seas for UPSC

Good to know

Each has distinct climate, salinity, and economic importance

Definition

Marginal seas are water bodies partially enclosed by land but connected to major oceans. They often have distinct characteristics due to their geographic position and surrounding landmasses.

Key Marginal Seas Comparison

Sea

Connected Ocean

Climate

Major Rivers

Economic Importance

Red Sea

Indian Ocean

Arid desert

None (seasonal streams)

Suez Canal trade route

Arabian Sea

Indian Ocean

Monsoon influenced

Indus River

Major shipping, fishing, oil

Mediterranean

Atlantic Ocean

Mediterranean climate

Nile, Po, Rhône

Ancient trade hub, tourism

Bay of Bengal

Indian Ocean

Tropical monsoon

Ganges, Brahmaputra

Cyclone formation, fishing

Persian Gulf

Indian Ocean

Arid, hot

Euphrates, Tigris

World's oil hub

Indian Ocean Marginal Seas

# Indian Ocean Marginal Seas
## Western Side
- Red Sea
- Arabian Sea
- Persian Gulf
## Eastern Side
- Bay of Bengal
- Andaman Sea
- South China Sea
## Southern Side
- Great Australian Bight
- Tasman Sea

Global Marginal Seas

Understanding marginal seas helps explain their distinct salinity and climate patterns
Understanding marginal seas helps explain their distinct salinity and climate patterns

Source: EduRev — Major Seas of the world | Geography for UPSC CSE PDF Download · edurev.in

Exam traps

Connection confusion: Red Sea connects to Indian Ocean via Gulf of Aden, not directly

Climate mixing: Don't assume all marginal seas have same climate - varies by location

Size vs importance: Arabian Sea is larger but Red Sea is strategically more important for trade

River inputs: Arabian Sea has major rivers, Red Sea doesn't - affects salinity significantly