Read a hydrograph and continental waters , glaciers and lakes

4. HOW TO READ AND INTERPRET A HYDROGRAPH • -Annual hydrograph shows how much water a river carries in a year.

• River regime is how this flow rises and falls.

• Vertical axis shows the discharge, o rate of flow • Horizontal axis indicates the months of the year.

• A line connects the data to show the river regime of a particular river.

4. HOW TO READ AND INTERPRET A HYDROGRAPH -

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HOW TO INTERPRET THE GRAPH The river regime can be simple or complex.

A river has a simple regime when it receives all of its water from a single source (rain or melting ice).

A river has a complex regime if it receives water from both rain and melting ice.

The flow of the river can be regular or irregular.

The river is regular in areas where rainfall is regular. (Saja river, Amazon river) The river is irregular in areas where there are rainy and dry seasons (JĂşcar River, Po river). There may be droughts during several months of the year.

5. CONTINENTAL WATERS: GLACIERS AND LAKES -

ICE CAPS AND GLACIERS Ice caps and glaciers hold 77% of the Earth’s fresh water.

The mass of ice increases in winter The mass of ice is reduced when part of the ice melts, in summer.

Ice are found in both hemispheres (Northern Hemisphere and Southern Hemisphere)

5. CONTINENTAL WATES: GLACIERS AND LAKES -

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LAKES Are large bodies of water that accumulate in inland basins.

They receive water from rivers, precipitation and groundwater.

They need to receive water continually.

Most lakes store fresh water Few lakes store saltwater because rivers transport mierals into these lakes and they lose water through evaporation.