Ppt class9 ch_4_climate(monsoon)part_2

Class 9 Social science Geography Chapter 4 Climate

1. THE INDIAN MONSOON BY : KAMLESH KHANNA

2. THE COLD WEATHER SEASON  (WINTER) Coldest month- December and January Temperature :Chennai 24°C– 28°C Northern plains 10°C–15°C Days - warm, nights - cold North East Trade winds (land - sea) Dry season Only Tamil Nadu gets rain Clear sky ,low temperature ,high humidity Cyclonic disturbances -North plain (Mediterranean sea) Winter rainfall - Mahawat (Rabi) Peninsular - does not have winter due to moderate influence of sea.

3. THE HOT WEATHER SEASON (SUMMER) Deccan Plateau —38°C March- May Gujarat ,Madhya Pradesh — 42°C North-Western parts of — 45°C Striking feature — Loo Strong, gusty ,hot ,dry winds —day Dust storms very common —May—Northern India Brings lower temperature, light rain, cool breeze Kaal Baisakhi —West Bengal Pre -monsoon showers in Kerala and Karnataka  helps in the early ripening of mangoes (mango showers)

4. ADVANCING MONSOON ( THE RAINY SEASON) Early June Low pressure —Northern Plains attract trade winds of the southern hemisphere Cross equator and blow in a South West direction entering the Indian peninsula as the south-west monsoon Winds blow over warm oceans ,bring abundant moisture Windward side of Western Ghats receives very heavy rainfall more than 250cm Maximum rainfall received in North eastern part, Mawsynram receives highest average rainfall in the world

5. FEATURES OF INDIAN MONSOON Monsoon is known for its uncertainty The alteration of dry and wet spells vary in intensity ,frequency and duration It causes heavy floods in one part, it may be responsible for droughts in the other It is often a regular in its arrival and its retreat Hence it sometimes disturbs the farming schedule

6. RETREATING / POST MONSOONS (THE TRANSITION SEASON) October- November low pressure trough over the northern plains becomes weaker  replaced by a high pressure system Marked by clear skies and rise in temperature  day temperature high  nights cool and pleasant The land still moist —owing to the conditions of high temperature and humidity. Weather becomes oppressive during the day (October heat) Tropical cyclones —very destructive

7. DIFFERENCE BETWEEN S.W.MONSOON & N.E.MONSOON S OUTH WEST MONSOON They blow in summer from June to September They blow from (high pressure) sea to (low pressure) land They are moisture bearing winds they blow in two branches Arabian sea branch, Bay of Bengal branch and give bulk of rainfall to India from 75 % to 90% High temperature, low pressure and high humidity NORTH EAST MONSOON They blow in winter from December to February They blow from (high pressure) land to ( low pressure) sea While crossing the Bay of Bengal they pick up moisture and give rainfall to the Coromandel coast (Tamil Nadu) Low temperature ,high pressure and low humidity

8. MONSOON AS A UNIFYING BOND Himalayas protect from extremely cold winds. This enables Northern India high temperature as compared to other areas on the same latitudes. Peninsular plateau under the influence of the sea from three sides, has moderate temperature. The Indian landscape ,its animals and plant life, its entire agricultural calendar and the life of people including their festivities, revolve around this phenomena. Monsoon winds bind the whole country by providing water to set the agricultural activities. The river valleys carry this water also unite as a single river valley unit.