Welcome students

GEOGRAPHY 1ST GRADE

 

 

Welcome back students. This year, you will have different subjects, including Maths, Technologies, English, Spanish, Sciences (Biology), Arts, and -of course- Geography among others.

Only two of these subjects will be completely taught in English : Technologies, and Geography.

 

Well, my name is Israel Castilla Domínguez, and I will be teaching you Geography during this year.

 

WHAT IS GEOGRAPHY?

Geography is the study of Earth’s landscapes, peoples, places and environments. It is, quite simply, about the world in which we live.

 

Geography informs us about

• The places and communities in which we live and work
• Our natural environments and the pressures they face
• The interconnectedness of the world and our communities within it
• How and why the world is changing, globally and locally
• How our individual and societal
  actions contribute to those changes
• The choices that exist in managing our world for the future
• The importance of location in business and decision-making

Hydrological cycle

It' the global circulation of water. Water is constantly moving in a cycle called the Hydrological cycle or water cycle. It's a giant closed system, the amount of water in the global water cannot change.

Water is held in a number of STORES, and them it moves by a series of flows or transfers.

• Atmosphere. Water exists there as water vapour or droplets in clouds
• Land. Water is also stored in rivers, lakes, and reservoirs. Plants also stores water. We may also find groundwater stores
• The sea. 95% of the water is stored in the sea. Almost all of it is found as liquid, but we may also find it as ice.

 

 

FLOWS or TRANSFERS

Water is always moving between the different stores by different ways such as:

 

• EVAPORATION: Water is converted from liquid into gas. This takes place from the water of the sea and from water sufaces (ponds, lakes, rivers)
• TRANSPIRATION: plants "breathe" water into the atmoshpere
• CONDENSATION: this is when cater cools and changes into liquid (in the atmosphere) taking the form of water droplets
• PRECIPITACION: this is the transfer of water from the atmosphere to the land or sea (rain, hail, snow)
• OVERLAND FLOW. Water on the ground moves and enters a stream, river or lake (run off).
• GROUNDWATER FLOW: This takes place in the aquifer or ground water
• INFILTRATION AND PERCOLATION: This is te transfer of water downwards through the soil into the groundwater store.
• THROUGHFLOW. Takes place bewteen the ground surface and the top of the groundwater store.

 

 

DRAINAGE BASINS

Every river has its own drainage basin  or catchmen area. Each drainage basin is a system and has a cycle. We can think of the drainage basin as the water cycle but in a smaller scale. The main difference between the water cycle and the drainage basin is that this one is an OPEN CYCLE.

 

Every drainage basin has INPUTS and OUTPUTS.

 

Inputs:

• Energy from the Sun
• Precipitation from outside the basin
• Possibly water from tributary drainage basins

 

 

Outputs:

• The river's discharge
• Evaporation and transpiration

 

 

A WATERSHED is the area of land where all of the water that is under it or drains off of it goes into the same place.

 

 

 

The main river borns in the higher parts of the basin close to the watershed. This is where most precipitacion falls. Smaller streams or tributaries enter the main river channel at locations known as confluences. The mouth or estuary of the river is where it flows out into the sea.

WEATHERING AND MASS MOVEMENT

Rivers play a major part in shaping landforms. This happens in three ways:

·         Erosion

·         Transport

·         Deposition

 

But not only rivers shape landforms. These river processes act in a sort of partnership with two other processes: WEATHERING AND MASS MOVEMENT

WEATHERING involves elements of the weather, particularly rainfall and temperature. There are three types of weathering:

·         PHYSICAL WEATHERING: This breaks rocks into smaller pieces. It’s done by changes in temperature.

·         CHEMICAL WEATHERING: This causes rock to decay and disintegrate (mainly by acidic rainfall.

·         BIOLOGICAL WEATHERING: The roots of plants, specially trees, break down the rocks

 

EROSION refers to the gradual destruction or diminution of something. Rivers may erode materials in different ways:

·         HYDRAULIC ACTION. Water hits the river bed very hard, and so the material is dislodged and carried away

·         ABRASION. The material being carried by a river is rubbed against the sides and floor of the channel.

·         CORROSION. Minerals in the rocks are dissolved by the water

The TRANSPORT is the movement of material (known as load) by the river. The water may carry different types of materials.  Whenever these materials stop moving or settle down, we might say that we have a DEPOSITION. Deposition is the laying down of material transported by the river. This happens when there is a decrease of energy, speed, and discharge of the river.

Water uses:  demand and supply

Only 3% of the water on Earth is fresh water. Over 75% is locked up in glaciers and ice sheets. 20 Percent is groundwater.

 

 

 

 

We need fresh water for different purposes:

·         INDUSTRIAL USE: Most factories are large consumers of water. Water is used for cooling machinery and to generate electricity.

·         DOMESTIC USE: Families need water to flush toilets, bathing, showering, drinking, watering the garden, etc.

·         AGRICULTURAL USE: Water is mainly used irrigation.

 

When talking about different water uses, it’s imperative mentioning about SUPPLY and DEMAND. Demand refers to the amount of water needed. Supply refers to the amount of water that we can obtain.

Demand obeys to different factors:

·         Rising standard of living-----piped water, flush toilets, showers, washing machines, swimming pools

·         A growing population

·         Agricultural productivity to feed the growing population

·         Industrialization

To meet the increasing demand, water is obtained from three different sources:

·         Rivers and lakes

·         Reservoirs: they are artificial lakes created by building DAMS

·         Aquifers and wells: much of the world’s fresh water lies underground