The hydrosphereThe hydrosphere is all the water on the

planet. It is made up of oceans, rivers, seas, lakes, glaciers, groundwater and water vapour

(clouds)

Water cycle 1. Evaporation: water evaporates.

2. Condensation: clouds formation.

3. Precipitation. Rain from clouds.

Hydrosphere

Saltwater (97% of Earth), in oceans and seas. - Salinity (amount of salt). Higher in hot and closed seas.

- Temperature: higher in the surface, colder in the deep. - Denser than fresh water.

Fresh water (3%), on continents and islands. - Most of it is at polar regions and glaciers. - Some groundwater. - Only al ittle in water vapour and lakes or rivers.

Oceans and seas.

Seas are oceanic waters close to continents. They are not as deep as oceans. Some are part of the ocean, other are connected through narrow straits. Some are interior.

Oceans are vast masses of saltwater separating the continents. They cover a large proportion of the Earth’s surface.

Some seas are extremelysalty, because of evaporationor human explotation. Life is difficult to find there.

The Aral Sea is an Example of a natural disasterProvoked by human hand.Overexplotation of rivers ledTo the drying out of the sea.

Main oceans and seas

Where are the oceans and seas located?

Water movement

• Waves: caused by…

• Tides: Caused by…

• Oceanic currents

Why tides happen…

Main ocean currents.

Ocean currents are large masses of water moving across the ocean. They are warm and cold currents, and they move because of their differencesIn density, salinity and temperature.

Currents and climate.

Newfoundland (Terranova, Canada) Brittany (Bretaña, France)

Temperature of ocean currents has a strong influence on climate. Brittany and Terranova are at the very same latitude; however, temperature differences are

Higher than 10 degrees during winter.

Rivers: flowing currents of water that

Stages of a river:-Upper course: flows rapidly, with river valleys.-Middle course: meandres.-Lower course: river flows slowly, river mouth.

Flow will be determined by rainfall and soil.

The rapid flow erodes easily the bedrockAnd creates sharp valleys(Los Pilones, Jerte)

UPPER COURSE OF A RIVER

Sand sediments on the lowerCourse of river Tietar, tributaryof river Tajo (Casatejada, Cáceres)

LOWER COURSE

MIDDLE COURSEMeanders of river Amazonas.

LOWER COURSEAluvial plane of river Guadalquir(Córdoba)

River mouths

Continental waters: ice caps and glaciers.

The mass of ice increases in winter andIs reduced when ice melts in summer.

Banquise(Newfoundland – Terranova Canadá)