• Climate of a country includes the study of temperature, rainfall, atmospheric pressure as well as the direction and velocity of winds over a arge period of time.

Introduction to Climate:

• The term "climate" originates from the Greek word Klima, signifying inclination, slope, or latitude.
• The climate is defined as the average meteorological conditions at a location over an extended period.
• Factors influencing climate include:
  • Latitudinal and longitudinal extent
  • Sea level
  • Distance from continents and oceans
  • Prevalent wind types
  • Precipitation patterns
  • Oceanic waves and currents
  • Relief features
  • Soil type
  • Local geographic characteristics

Classification of Climate:

• The Greeks pioneered climate classification based on temperature, distinguishing between warm temperate and cold zones. These zones gradually extend from the Equator to the poles.
• The continent of Asia spans from the Equator to the North Pole, encompassing diverse climate zones.
• Regions with consistent climates are termed climatic regions.
• Key factors include latitude, altitude, proximity to the sea, temperature, vegetation types, and the impact of evaporation. Among these, latitude is the primary determinant of an area's climate.

Diagrammatic Representation of World Climate

Koeppen's Scheme of Classification of Climate

• The most widely used classification of climate is the empirical climate classification scheme developed by V Koeppen.
• Koeppen identified a close relationship between the distribution of vegetation and climate.
• He used the values of temperature and precipitation and related them to the distribution of vegetation and used these values for classifying the climates.
• It is an empirical classification based on mean annual and mean monthly temperature and precipitation data.
• He used capital and small letters to designate climatic groups and types.
• Koeppen recognised five major climatic groups, four of them are based on temperature and one on precipitation.
• The capital letters A, C, D and E delineate humid climates and B dry climates.
• The climatic groups are sub-divided into types, designated by small letters, based on seasonality of precipitation and temperature characteristics
• The seasons of dryness are indicated by the small letters f, m, w and s. (f-no dry season), (m-monsoon climate), (w-winter dry season) and (s-summer dry season).

Climate Types According to Koeppen

• The lowercase letters a, b, c, and d denote the severity of temperature.
• The B-Dry climates are further categorized using capital letters S for steppe or semi-arid and W for deserts.

Group A: Tropical Humid Climates:

• Tropical humid climate spans between the Tropic of Cancer and Tropic of Capricorn, characterized by the Sun being overhead throughout the year and the presence of the Inter Tropical Convergence Zone (ITCZ), resulting in a hot and humid climate.
• The annual temperature range is minimal, with high annual rainfall. The tropical group comprises three main types:

Tropical Wet Climate (Af):

• Found near the Equator in areas such as the Amazon Basin in South America, Western equatorial Africa, and the islands of the East Indies.
• Experiences significant rainfall every month, with thunder showers in the afternoon.
• Uniformly high temperature with negligible annual temperature range, fostering tropical evergreen forests with dense canopy cover and large biodiversity.

Tropical Monsoon Climate (Am):

• Present over the Indian subcontinent, Northern Australia, and the North-Eastern part of South America.
• Heavy rainfall occurs mainly in summer, while winters are dry.

Tropical Wet and Dry Climate (Aw):

• Found North and South of Af-type climate regions, bordering dry climate on the Western part and Cf or Cw on the Eastern part.
• Savannas grow in tropical regions 8° to 20° from the Equator, characterized by warm to hot conditions in all seasons.
• Mean annual precipitation ranges from 80 to 150 cm, with a dry season typically longer than the wet season. Savanna landscapes feature tall grass and short trees, known as bush-veld, providing a habitat for diverse animals.
• Extensive Aw climate is found to the North and South of the Amazon forest in Brazil, adjoining parts of Bolivia and Paraguay in South America, Sudan, South and Central Africa.

Group B: Dry Climates:

• Characterized by very low rainfall inadequate for plant growth, covering large latitudes from 15° to 60° North and South of the Equator.
• Divided into Subtropical Steppe (BSh), Subtropical Desert (BWh), Mid-latitude Steppe (BSk), and Mid-latitude Desert (BWk).
• Subtropical Steppe (BSh) and Subtropical Desert (BWh):  Located in the transition zone between humid and dry climates.
•  Subtropical Steppe receives enough rainfall for sparse grassland growth, while variability in rainfall affects life more in the Steppe than in the desert, often causing famine.
• Mid-latitude Steppe (BSk) and Mid-latitude Desert (BWk): Occur between latitudes 35°-60°, with Mid-latitude Steppe receiving more precipitation than Mid-latitude Desert.
• Both are confined to the interior of continents, where maritime-humid winds do not reach, and in areas often surrounded by mountains.

Group C: Warm Temperate (Mid-Latitude) Climates:

• Warm temperate (mid-latitude) climates span from 30°-50° of latitude, primarily on the Eastern and Western margins of continents, characterized by warm summers and mild winters. 
• They are categorized into three types:

Humid Subtropical (Cfa) Climate:

•  Located on the Eastern parts of the continent in subtropical latitudes.
•  Air masses are generally unstable, leading to year-round rainfall.
• Found in the Eastern United States of America, Southern and Eastern China, Southern Japan, North-Eastern Argentina, coastal South Africa, and Eastern coast of Australia.
•  Annual precipitation averages vary from 75-150 cm, with thunderstorms in summer and frontal precipitation in winter. Mean monthly temperature in summer is around 27°C, and in winter, it varies from 5°-12°C, with a small daily temperature range.

Mediterranean Climate (Cs):

• Occurs around the Mediterranean Sea and along the West coast of continents in subtropical latitudes (30°-40° latitudes), e.g., Central California, Central Chile, and along the coast in South-Eastern and South-Western Australia.
• Influenced by subtropical high in summer and Westerly wind in winter, resulting in a hot, dry summer and mild, rainy winter.
• Monthly average temperature in summer is around 25°C, and in winter, it is below 10°C. Annual precipitation ranges between 35-90 cm.

Marine West Coast Climate (Cfb):

• Located poleward from the Mediterranean climate on the West coast of continents.
• Main areas include North-Western Europe, West coast of North America, North of California, Southern Chile, South-Eastern Australia, and New Zealand.
• Moderate temperatures due to marine influence, with warmer winters than expected for the latitude. Mean temperature ranges from 15°-20°C in summer and 4°-10°C in winter. Annual and daily temperature ranges are small. Precipitation occurs throughout the year, varying from 50-250 cm.

Group D: Cold Snow Forest Climate:

• Cold snow forest climates are present in the large continental area in the Northern hemisphere between 40°-70° North latitudes in Europe, Asia, and North America. Divided into two types:

Humid Continental (Df):

• Cold climate with humid winters, located poleward of the marine West coast climate and mid-latitude steppe.
• Cold and snowy winters with a short frost-free season. Large annual temperature ranges, abrupt and short weather changes. More severe winters poleward.

Subarctic (Dw):

• Cold climate with dry winters, mainly in North-Eastern Asia.
• Pronounced winter anticyclone development and summer monsoon-like reversal of wind. Extremely low winter temperatures, and precipitation occurs in summer. Low annual precipitation from 12-15 cm.

Group E: Polar Climates:

• Polar climates exist poleward beyond 70° latitude and consist of two types:

Tundra Climate (ET):

• Named after the vegetation, including low-growing mosses, lichens, and flowering plants.

• This is the permafrost region where the subsoil remains permanently frozen.
• The brief growing season and waterlogging support only low-growing plants.
• During summer days, tundra regions experience exceptionally long daylight hours.

Ice Cap Climate (EF):

• The ice cap climate (EF) prevails over interior Greenland and Antarctica, where temperatures remain below freezing even in summer.
• This area receives minimal precipitation. Accumulated snow and ice undergo pressure-induced deformation, leading to ice sheet breakage.
• These broken fragments, known as icebergs, float in the Arctic and Antarctic waters.
• Plateau Station in Antarctica, situated at 79°S, exemplifies this climate.

Highland Climates (H):

• This climate is observed in high mountainous regions, encompassing single peaks like Mount Kilimanjaro and vast elevated areas such as the Plateau of Tibet.
• In high mountains, significant temperature fluctuations occur over short distances.
• Precipitation types and intensity exhibit variations in these elevated terrains.

Prelims facts

• The main factor which determines the climate of any - area is?

Types of vegetation [UPPSC (Pre) 2010]

• The seasonal reversal of winds is the typical characteristic of

-Monsoon Climate (APSC (Pre) 2014

• The reason of high annual range of temperature in the Interior of continent as compared to coastal areas is -Thermal differences between land and water [IAS (Pre) 2013)
•  In which season the air pressure is lowest?

- Summer season [UPPSC (Pre) 2014]

• Which continent has all types of climatic zones?

Asia (UPPSC (Mains) 2016)

• Characteristics of warm and dry climate, mild and wet winter and evergreen oak trees are related to -Mediterranean Region [IAS (Pre) 2010]
• What is the characteristic climate of the tropical Savannah region? -Dry and Wet season [IAS (Pre) 2012]
•  In which region the climate is extreme, rainfall is scanty and the people used to be nomadic herders?

- Central Asian Steppe [IAS (Pre) 2013

• In the China type climate the rainfall occurs -Throughout the year (IAS (Pre) 2002)
•  Mediterranean regions have rainy winters because During winter they lie in the belt of westerlies

[UPPSC (Mains) 2004]

• When does the Mediterranean region receive heavy rainfall?

Winter (MPPSC (Pre) 1999)

• Which type of climates are associated with the shifting of the pressure belts? - Mediterranean and Monsoon Climate

[UPPSC (Mains) 2020]

• For short-term climatic predictions, which event is associated with occasional weak monsoon rain in the Indian subcontinent?

-El-Nino and Southern Oscillations [IAS (Pre) 2002)

• In which part of the ocean El-Nino develops?

- Pacific Ocean [UPPSC (Mains) 2015]

• In which region of the world are nights the winters?

- Tropical Desert Region (MPPSC (Pre) 2011]

• The wettest inhabited place in the world is

- Mawsynram (UPPSC (Pre) 2001]

• Slash and Burn is the characteristic which climatic regions of agriculture in

Monsoon Climate Region [MPSC (Pre) 2016]

• 'Vegetation is the true index of climate' statement is

- Koeppen [UPPSC (Pre) 2018

Self Check

1. Hot desert regions are found mostly in the Western part of the continents between which latitudes?

(a) 15-30° North/South

(b) 30°-60° North/South

(c) 60-75 North-South

(d) 75°-90° North South

2. Match List I with List II and select the correct answer by using the codes given below the lists.

UPSC (Pre) 2014

List I (Regions)

A California

1. West Australia
2. Bangladesh
3. Siberia

List II (Type of climates)

1. Mediterranean
2. Tropical monsoon
3. Cold temperate
4. Hot desert

Codes

(a) 1 2 3 4

(b ) 14 23

(c)2 3 4 1

(d) 2 413

3. What could be the main reason/reasons for the formation of the African and Eurasian desert belt?  UPPSC (Pre) 2011

1. It is located in the subtropical high pressure cells.
2. It is under the influence of warm ocean currents.

Which of the statement(s) given above is/are correct in this context?

(a) Only 1

(b) Only 2

(c) Both 1 and 2

(d) Neither 1 nor 2

4. 'Climate is extreme, rainfall is scanty and the people used to be nomadic herders. The above statement best describes which of the following regions? UPPSC (Pre) 2013 

(a) African Savanna

(b) Central Asian Steppe

(c) North American Prairie

(d) Siberian Tundra

5. Which one of the following climates are associated with the shifting of the pressure belts? UPPSC (Mains) 2010

1. Equatorial climate
2. Mediterranean climate
3. Monsoon climate
4. Western European climate

Codes

(a) 1 and 2

(b) 1 and 3

(c) 2 and 3

(d) 2 and 

6. Which one of the following pairs is correctly matched?

UPPSC (Mains 2004 

(a) Wet winter dry summer: Italy

(b) Wet throughout the year: Sudan

 (c) Wet summer dry winter: Iran

(d) Dry throughout the year: Chile

7. Match List I with List II and select the corten answer by using the codes given below the list

List I (Types of climate)

1. Equatorial
2. Mediterranean
3. Monsoon
4. Savanna

List II (Regions)

1. California
2. Bangladesh
3. Sudan
4. Congo

Codes

(a) 4 1 2 3

(b) 2314 

(c) 1 2 3 4

(d) 4 3 2 1

8. A geographic region has the following distinct characteristics. LAS (Pre) 2010

1. Warm and dry climate 
2. Mild and wet winter
3. Evergreen oak trees.

The above features are the distinct characteristics of Which one of the following regions?

(a) Mediterranean

(b) Eastern China

(c) Central Asia

(d) Atlantic Coast of North America

9. Consider the following statements.

1. In Equatorial regions, the year is divided into four

main seasons.

2 . In the Mediterranean region, summer brings me rain.

3. In China type climates, rainfall occurs throughout the year.
4. Tropical highlands exhibit vertical zonation of different climates.

Which of these statement(s) is/are correct

(a) All of these

(b) 1, 2 and 3

(c) 1, 2 and 4

(d) 3 and 4

Know Right Answer

1 (a)

2 (b)

3 (a)

4 (d)

5 (c)

6 (a)

7 (a)

8 (a)

9 (d)