This document discusses the importance of water and provides details on the water cycle. It notes that water is essential for survival and describes how rain formed millions of years ago, creating oceans and lakes. It then explains the water cycle, including evaporation, condensation, and precipitation, before describing different types of rainfall (relief, convection, frontal). The document also outlines some issues around water availability, noting that some countries experience flooding while others suffer from water shortages.
The total volume of water on Earth is estimated at 1.386 billion km³ (333 million cubic miles), with 97.5% being salt water and 2.5% being fresh water. Of the fresh water, only 0.3% is in liquid form on the surface. In addition, the lower mantle of inner earth may hold as much as 5 times more water than all surface water combined (all oceans, all lakes, all rivers).
This slides of class 7 Geography, chapter 3 ,Our Changing Earth part -2 ,
in this presentation describe exogenic force agents ;Water,Wind,Sea Weaves,and Glacier.
this is useful for teachers and students of Chhattisgarh board and CBSE Board for teaching and understanding .
there is good photos in example.
also available teaching video in you tube GURU's Channel.
https://www.youtube.com/channel/UCuf04TA3UGuLDtnlOkJVntA
Scarcity of freshwater is a defining feature of planet Earth. This EcoWest.org presentation shares graphics that visualize our most precious natural resource.
The total volume of water on Earth is estimated at 1.386 billion km³ (333 million cubic miles), with 97.5% being salt water and 2.5% being fresh water. Of the fresh water, only 0.3% is in liquid form on the surface. In addition, the lower mantle of inner earth may hold as much as 5 times more water than all surface water combined (all oceans, all lakes, all rivers).
This slides of class 7 Geography, chapter 3 ,Our Changing Earth part -2 ,
in this presentation describe exogenic force agents ;Water,Wind,Sea Weaves,and Glacier.
this is useful for teachers and students of Chhattisgarh board and CBSE Board for teaching and understanding .
there is good photos in example.
also available teaching video in you tube GURU's Channel.
https://www.youtube.com/channel/UCuf04TA3UGuLDtnlOkJVntA
Scarcity of freshwater is a defining feature of planet Earth. This EcoWest.org presentation shares graphics that visualize our most precious natural resource.
Description about hydrological cycle, how water lost, condense and replenish on earth. It explains the process of hydrological cycle and factors influencing hydrological cycle.
Biogeochemical cycle, any of the natural pathways by which essential elements of living matter are circulated. The term biogeochemical is a contraction that refers to the consideration of the biological, geological, and chemical aspects of each cycle.
A very interesting presentation about the Galapagos Islands in the Pacific Ocean. These islands became famous due to the visit by Charles Darwin who promoted the Theory of Evolution.
2. Why is water so important?
• Water is one of our resources to survive.
• We need water to clean dishes, to keep
ourselves clean, to water plants … and so
on.
• Without water, the whole planet wouldn’t
survive.
3. Waters’ history
Millions of years ago, the Earth was just rock and magma.
The Earth did not have rain but it had the materials from
volcanic gases. Hot gases rose in the air and cooled, creating
rain. It rained for days and created oceans and lakes. From
there the Earth started.
If rain didn’t exist, there would be no life on Earth.
The planet needs water as much as we do.
4. How can we get water?
• Water comes in different ways, we can get
water from lakes, we can purify it using the
reverse-os-mosis.
• We can get water from rain, we purify it.
• We can also take up water from boreholes
stored underground.
5. • Farmers need more water than us .
• They need water for watering plants to
grow vegetables and fruits, they also need
water to drink and use water for there
everyday lives.
• Most farmers take up water from
boreholes
6. • We can get water from rain.
• Rain comes in three types:
Relief rainfall, Convection rainfall and
Frontal rainfall.
7. Relief rainfall
• This type of rainfall comes from the
mountains.
• The warm air rises over mountains, the air
condenses and cools, making rainfall.
8. Convection rainfall
• This type of rainfall comes from the
ground.
• The ground is heated by the sun causing
the warm air to rise, when the warm air
rises it condenses and rain falls.
9. Frontal rainfall
• Frontal or cyclonic rainfall is when a mass
of warm air meets a mass of cold air.
• The point where these two meet is called
the front.
10. • These types of rainfall are also sources of
water, the warm air is forced to rise since
it is lighter than cool air.
• This depends on the temperature from the
sun and if the sky is cold.
12. The water cycle
• Water can be in the state of a liquid solid and gas.
• Evaporation happens when the warm winds blow over oceans and
seas, the water on top evaporates, so the water changes from a
liquid to a gas. Evapotranspiration happens when the water
evaporates from trees and plants. The warm air rises and
condenses, this is called condensation, when the water droplets
become too heavy to carry, they start to fall to the ground, this
process the called precipitation.
• The water cycle mostly happens in the form of rain, when it falls
overland, water runs into streams, rivers and back to the sea to start
the cycle.
• The water cycle is also called the Hydrological cycle.
13. Problems involving water
• In some countries, there are problems in
water. Some countries have less water
than others, or some countries suffer from
flooding.
• These two problems decrease the
population of the country, making it hard to
survive.
14. Flooding
• One of some countries that suffer flooding
is Bangldesh.
• Bangladesh suffered flooding in
1954,1955,1956,1962,1963,1968,1970,
1971,1974,1984,1987 and 1988.
• The flooding came from both human and
natural causes.
15. Shortage of water
• Some countries do not have lakes or rain
to get water from, so they suffer complete
dryness.
• To dry and hot countries water is rare.
• In these countries water is hard to get,
they get it from boreholes.