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Water on Earth

Water on Earth

The hydrosphere refers to the total amount of water in the Earth. It includes water on the surface of the planet, underground and in the air.
SALT WATER FRESH WATER
Waves
Atlantic Ocean, Valdoviño beach. Yolanda Varela. (CC-BY-NC-SA)
 97.5% of water in the planet is salt water. It is considered salt water because it has an average salinity of 35% or more.
Salt water
Fresh water
 It is water that has little salts and dissolved solids. Only 2.5% of water in the Earth is fresh water.
Barosa waterfalls
Barosa waterfalls, Pontevedra. Yolanda Varela. (CC-BY-NC-SA)
Taormina, Mediterranean
Taormina, Mediterranean Sea. Fernando García Redondo. Flickr. (CC-BY-NC)

MEDITERRANEAN SEA

It has a salinity of 38% because of its high evaporation and small connection to the Atlantic Ocean.
Mediterranean
Lakes

LAKES

It is a body of water that occupies an inland basin of appreciable size. Lakes and rivers represent 1% of fresh water.
Ingalls Lake
Ingalls Lake. Thales. Flickr. (CC-BY)

RED SEA

It contains the hottest and saltiest seawater. It is connected to the Mediterranean via the Suez Canal.
Red Sea
Red Sea. Miriam Mezzera. Flickr. (CC-BY)
Red Sea
Rivers
Lerez River
Lerez River, Pontevedra. Yolanda Varela. (CC-BY-NC-SA)

RIVERS

They are a natural wide flows of fresh water across the land into the sea, a lake or another river.  Rivers and lakes represent 1% of fresh water.
Glacier
Groundwater
Glaciers
Argentinian glacier. 12019.
Pixabay. (Pixabay Licence)

GLACIERS

They contain 69% of fresh water in solid form.

GROUNDWATER

It is the water that exists below the surface of the Earth. Ii is 30% of fresh water.
Wookey Hole
Wookey Hole. Evil Nick. Flickr. (CC-BY-NC)

Activity 1

1. Complete with the missing letters.
1. SA T    WAT R 2. MEDIT RRA EAN
Cies Islands on the Atlantic Ocean

Cies Islands on the Atlantic Ocean.
Yolanda Varela. (CC BY-NC-SA)
3. LA ES 4. GL CIE S
6. S LI ITY 7. BA IN
3. RI ERS 5. GRO ND ATER

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Activity 2

2. Listen and write the word.
Blue Lagoon, Iceland
Blue Lagoon, Iceland. Verti Watkin. flickr (CC-BY)

 

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Activity 3

3. Relate these data to one of the items studied above.
a. 35% salinity.
b. Ice water.
c. It flows to the sea.
d. It contains little salt.
e. Suez Canal connects it to the Mediterranean.
f. It includes water in the air.
g. 38% salinity.

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