What is hydrosphere

Hydrosphere 

What is hydrosphere? 

1. Water components on earth
2. 71% of total surface is water
3. Therefore it is called Water planet, blue planet

Water cycle

 The hydrological cycle consist of
1. Evaporation
2. Condensation
3. Precipitation
4. Collection

Classification of RAINFALL 

1. Conventional-almost daily in equator
2. Orographic –rain fed and rains shadow
3. Cyclonic/frontal –warm air mass converges with cold

The Pacific ocean- 

1. largest ocean, deepest ocean
2. one-third of the earth’s surface
3. Triangular in shape
4. Mariana trench (11,033 m deep) is located here.
5. Albatross plateau is located here.
6. Important Islands-British Columbia and Chile Islands (east)
7. Kurile, Japan, Philippines, New Zealand (west)
8. Important sea-Bering Sea, Sea of Japan, East China Sea, South China Sea, Gulf of California

The Atlantic Ocean-

Busiest Ocean Half of Pacific Ocean
It is “S” letter shape Trenches- Romanche,
South Sandwich Important sea-Baffin Bay, Hudson Bay, North sea, Mediterranean sea, Caribbean sea, Gulf of Mexico

1. The Indian Ocean- named after India
2. Sunda Trench is present here,
3. linear deeps are almost absent
4. Islands-Andaman and Nicobar, Sri Lanka, Madagascar, Lakshadweep, Maldives, Mauritius

Major division of the ocean floor- 

1. Continental shelf- boarder of the continent

- Slope <1 degree - Max depth 200 meters 

2. Continental slope – edge of continental shelf

 - Steep seaward slope - 2-5 degree slope 

3. Continental rise-beyond continental slope

- 0.5-1 degree - With depth merges with abyssal plain 

4. Abyssal plain<1 degree

- 40%of ocean floor

Vertical and Horizontal Distribution of Temperature 

1. Temperature decreases with depth. 

2. Thermocline-boundary below which temperature is different 

3. 100-400 metres 

4. 90% volume is below thermocline

1. Temperature decreases from equator towards pole

 2. 27degree in tropical to 0 degree in poles 

3. Average temp 17 degree 

4. 90% volume is below thermocline

 Salinity 

1. It Define the total content of dissolved salts in sea water. 

2. Expressed in Parts per thousand(ppt) or % 

3. Low at equator due to rainfall and big rivers like Amazon and Zaire(35)

 4. Very low at poles, little evaporation and melting of ice (20-32) 

5. Highest- Tropics due to active evaporation (37). Indian ocean (35) 

6. Indian Ocean (35) Lower salinity in Bay of Bengal, due to influx of river water. 

TIDES 

– Due to gravitational pull of the sun and moon 

– Centrifugal force caused by earth’s rotation

• Spring tide- highest 

• On full moon and new moon 

• Neap tide-Low amplitude 

• Moon in first and last quarter