R.L. Singh divided India into 10 climatic divisions based on temperature and rainfall characteristics. The divisions include: 1) Per Humid North-East covering northeastern states with July temperatures of 25-33°C and annual rainfall over 200cm. 2) Humid Sahyadri and West Coast along western India with January temperatures of 19-28°C and annual rainfall over 200cm. 3) Humid South-East covering eastern states with January and July temperatures of 12-27°C and 26-34°C respectively, and annual rainfall of 100-200cm.

1. CLIMATIC CLASSSIFICATION OF INDIA BY R.L.
SINGH

2. INTRODUCTION
INDIA’S CLIMATIC CLASSIFICATION BY R.L. SINGH
Following Kendrew and stamp, dr. R.L. Singh presented his climatic
divisions of India in 1971. He divided the country into 10 climatic divisions
based on the temperature conditions of the hottest and the coldest months
and average annual rainfall.

3. 10 CLIMATIC DIVISIONS BY R.L. SINGH
1. Per Humid North-East:
 As Per name indicates, it covers most parts of the north-eastern states including Sikkim,
Assam, Arunachal Pradesh, Nagaland, Tripura, Mizoram, and Meghalaya.
 The July temperature is 25°-33°C which falls to 11°-24°C in January.
 The average annual rainfall at most of places is 200 cm although there are places which
record over 1,000 cm of rainfall.
2. Humid Sahyadri and West Coast:
 It includes Sahyadri (Western Ghats) and its western coastal belt extending from Narmada
Valley in the north to Kanyakumari in the south.
 Temperature in January is 19°-28°C which rises to 26°-32°C in July.
 The average annual rainfall is about 200 cm but at places it may be much higher especially on
the western slopes of the Western Ghats.
3. Humid South-East:
 Orissa, West Bengal, Chhattisgarh and Jharkhand are included in it.
 January and July temperatures are 12°-27°C and 26°-34°C respectively.
 The average annual rainfall is 100-200 cm.

4. 4. Subhumid Transition:
 It embraces the eastern part of Uttar Pradesh, Bihar and northern part of Jharkhand.
 January temperature is 9° to 24°C which rises to 24°-41°C in July.
 The average annual rainfall is 100-200 cm.
5. Subhumid Littorals:
 Eastern Tamil Nadu and coastal Andhra Pradesh have subhumid littoral climate.
 May is the hottest month when the temperature rises to 28°-38°C.
 In January the temperature falls to 20°-29°C. Summers are dry but winters are wet.
 The area as a whole receives 75-150 cm annual rainfall, most of which is caused by retreating
monsoons in November-December.
6. Subhumid Continental:
 This climate is primarily found in the Ganga plain where January and July temperatures are 7°-
23°C and 26°-41°C respectively.
 The average annual rainfall varies from 75 to 150 cm.

5. REPRESENTATION OF CLIMATIC CLASSIFICATION OF INDIA BY R.L. SINGH THROUGH
DIAGRAM

6. 7. Semi arid and Subtropical:
 This climate prevails in the Satluj – Yamuna water divide which includes Punjab, Haryana,
eastern Rajasthan and the Union Territories of Delhi and Chandigarh.
 The average rainfall is 25 to 100 cm, most of which falls in summer.
 Some rainfall is caused in winter by western disturbances. January temperatures are 6°-
23°C which rise to 26°-41°C in May.
8. Semi arid Tropical:
 Large parts of Gujarat, Maharashtra, Madhya Pradesh, Chhattisgarh, Karnataka and
Andhra Pradesh have semi arid tropical climate.
 Temperature varies from 13°-29°C in January and from 26°-42°C in July. The average
annual rainfall varies from 50 to 100 cm.

7. 9. Arid:
 The areas of arid climate comprise the Thar desert and includes western Rajasthan, south-
west Haryana and Kuchch region of Gujarat.
 This is extremely dry climate in which the annual rainfall is only 25 cm and at places it is as
little as 10 cm.
 January temperatures are 5°-22°C which rise to 20°-40°C in June.
 The range of temperature, both diurnal and annual, is very large.
10. West Himalayan:
 This climate is found in west Himalayan region which includes Jammu and Kashmir,
Himachal Pradesh and Uttaranchal.
 The July temperature is 5°-30°C which dips to 0°-4°C in January.
 The annual rainfall is 150 cm.
 The rainfall is caused by south-west monsoons in summer and by western disturbances in
winter.

8. CONCLUSION
The contribution of DR. R.L. Singh as an Indian Geographer is very
important. As an Indian geographer he could specially categorise the
India's regions according to climatic differences. The 10 classifications by
R.L Singh has been proven very useful to study the different regions of
India having different charecteristics.