The Climate of India

 The whole of India has a tropical monsoonal climate, since the greater part of the country lies within the tropic and the climate is influenced by the monsoons.







 The position of the mountain ranges and direction of the rain-bearing winds are the two main factors that determine the climate of India.



 Alternating seasons is the chief characteristic of India’s climate.

 Latitude : India lies between 8 N and 37 N latitudes. The Tropic of Cancer passes through the middle of India, thus making the southern half of India in the Torrid Zone and the northern half

in the Temperate Zone.

 Himalayan Mountains: The Himalayas play an important role in lending a sub-tropical touch to the climate of India.



 The lofty Himalaya mountains form a barrier which affects the climate of India.



It prevents the cold winds of north Asia from blowing into India, thus protecting it from severly cold winters.



 It also traps the monsoon winds, forcing them to shed their moisture within the sub-continent.



 Altitude : Temperature decreases with height. Place in the mountains are cooler than places on the plains.







 Distance from the sea : With a long coastline, large costal areas have an equable climate. 



Areas in the interior of India are far away from the moderating influence of the sea. Such areas have extremes of climate.

Geographical Limits

 Western Disturbances : The low pressure system that originate over the eastern Mediterranean region in winter and move eastwards towards India passing over Iran, Afghanistan and Pakistan are responsible for the winter rain in northern India.

 Conditions in the Regions Surrounding India : Temperature and pressure conditions in East Africa, Iran, Central Asia and Tibet determine the strength of the monsoons and the occasional

dry spells. For example, high temperatures in East Africa may draw the monsoon winds from the Indian Ocean into that region thus, causing a dry spell.

 Conditions over the ocean : The weather conditions over the Indian Ocean and the China Sea may be responsible for typhoons which often affect the east coast of India.

 Jet Streams : Air currents in the upper layers of the atmosphere known as jet streams could determine the arrival of the monsoons.



The upper air circulation in this region is dominated by a westerly jet streams because they are located approximately over 27-30 north latitude.









 The westerly jet streams are responsible for the western cyclonic disturbances in the north and north-westren parts of India.



The subtropical westerly jet stream moves north of the Himalayas with the apparent movement of the Sun.

 The tropical jet stream (an easterly jet stream) blows over the Indian Peninsula; approximately over 14 north during the summer months.

Climatic Regions of India

Following are the climatic region of the India :

Tropical Rain forest

 This type of climate is found on the west coastal plain and Sahyadris and in parts of Assam.





 The temperature are high, not falling below 18.2 C even during winter and rising to 29 C in April

and May, the hottest months.







 Dense forests and plantation agriculture with crops like tea, coffee and spices are the

characteristics vegetation in the area.

Tropical Savanna

 Most of the peninsula, except the semiarid zone in the leeside of the Sahyadris experiences this

type of climate.



 A long dry weather lasting through winter and early summer and high temperature remaining

above 18.2 C even during the winter season and rasing as high as 32 C in summer are the chief

characteristics of this climate.







 Nagpur has a mean temperature of 35.4 C degree C for May which is the hottest month and 20.7

C for December the coldest month in the year.



 The natural vegetation all over the area is savanna.

Tropical Semi-Arid Steppe Climate



 The rain-shadow belt, running south-ward from central Maharastra to Tamil Nadu, in the leeside

of the Sahyadris and Cardomom Hills come under this type of climate of low and uncertain

rainfall.



 Temperature varying from 20 C to 23.8 C for December and 32.8 C for May. Agriculturally, the

climate is suitable only for dry farming and livestock rearing.

Tropical and Sub-Tropical Steppe



 This type of climate occurs over a broad crescent from Punjab to Kachchh between the That

Desert to its west and the more humid climates of the Ganga Plain and the Peninsula to its east

and south respectively.







 The climate, therefore, is transitional between these two areas. The annual rainfall is not only

low but it is also highly erratic.

Tropical Desert

 The western part of Barmer, Jaisalmer and Bikaner district of Rajasthan and most of the parts of

Kachchh form the sandy wastes of the Thar which experiences a typical desert climate.



 Ganganagar has rcorded a maximum temperature of 50 C the highest record.

Humid Sub-Tropical with Dry Winter

 A large area to the south of the Himalayas, east of the tropical steppe and north of the tropical

savanna running in a long belt from Punjab to Assam with a south-westward extension into

Rajasthan east of the Aravalli Range, has this type of climate.









 Winters are dry except for a little rain received from the westerly depressions.

Mountain Climate



 The Himalayan and Karakoram ranges experience this type of climate with sharp contrasts between the temperatures of the sunny and shady slopes, high diurnal range of temperatures and high variability of rainfall.



 The trans-Himalayan region, Ladakh, where the south-west monsoon fails to reach, has a dry and cold climate and a spare and stunned vegetation.

Drought in India



 The dry areas of Rajasthan and the abjoining parts of Haryana and Gujarat are liable to frequent drought conditions.







 Another area liable to frequent drought lies on the leeward side of the Westren Ghats.

Rainfall in India



The two significant features of India’s rainfall are that:



i. In north India, rainfall decreases westwards.

ii. In Peninsular India, except Tamil Nadu , it decreases eastward.