2.6 How does the hydrosphere provide natural resources? Introduction • Ask them what they already know about the distribution of water across the globe. • Explain Diagram B. What is hydrosphere and how many types are there? • Hydrosphere is component of earth which is made up of all liquid water we find on the planet • It is vital for sustaining aquatic ecosystems and influencing the global climate • The components are oceans, freshwater, surface water, groundwater, glacial water, and atmospheric water vapor https://youtu.be/otrpxtAmDAk?si=TQB9KVNvpXEuzW0X Fresh water scarcity Facts to remember 1. Water is one of the most important substances on Earth. All plants and animals must have water to survive. If there was no water there would be no life on Earth. 2. The water cycle is the cycle of processes by which water circulates between the Earth’s oceans, atmosphere, and land. It involves processes like evaporation, condensation precipitation and runoff. 3. How water interconnects the lithosphere, biosphere and atmosphere • Water continuously moves between the oceans, atmosphere, and land, powered by the Sun. • Heat from the Sun causes water on the land and in the oceans to evaporate into gas. • As the air rises and cools, the gas condenses into water droplets, which can fall as rain. • This water can be stored in glaciers, vegetation, or flow into rivers, which eventually return it to the oceans. This cycle repeats endlessly. 4. 97.5% of all water is salt water in seas and oceans. The remaining 2.5% of water is fresh water. - 79% of the Earth's fresh water is locked in glaciers, 20% is underground as groundwater, and only 1% is readily accessible. Of this accessible water, 52% is in lakes, 1% in rivers, 38% in soil, 1% in living organisms, and 8% as water vapor in the atmosphere. Just over half of the accessible fresh water is available for human use. 5. Water scarcity exists in areas of the world where demand for water exceeds supply. - Causes of water scarcity Low rainfall, too many people, overuse of existing water, plenty of water but lack of access due to limited use of technology e.g. pumps to bring groundwater to surface Activities (page-33) Answer these questions in your Geography exercise book. 8 Activities (page-33) Answer Thanks for your attention. 2.7 Why is the world so dependent on oil resources? Introduction • Discuss how we use oil and how it affects our lives. • Explain what crude oil and natural gas is. • Watch a video clip. What is oil and how is it formed, where do we use oil? • Oil and coal are fossil fuels and oil is formed as a liquid state but coal is formed as a solid state • They are formed from the fossils of plants and sea creatures • Oil is used to fuel cars, ships and planes, to generate electricity and to produce plastics and fertilizers even clothes • Up until the middle of eighteenth century, people burnt whale oil to produce artificial light with lamps • Invention of car and electric light bulb helped transform us into an oil dependent world How petroleum and natural gas were formed! https://youtu.be/UPAqfTNiais?si=3vk84NpCQVSpSuLc Oil https://youtu.be/-njmj0diWu8?si=4GpYNq-T92g1kC8w Natural gas Facts to remember (Activities Pg. no-35) 1. Crude oil is oil in its raw state when extracted from the ground. Natural gas is a naturally occurring hydrocarbon gas mixture consisting primarily of methane. 2. How oil and gas are formed and extracted! -Oil and gas formed between 300 and 400 million years ago from the tiny sea creatures. Over long periods of time these remains were covered by new layers of sediment and rock. Over millions of years, heat and pressure turn buried remains into oil and gas, which can either seep to the surface or get trapped in rock layers. 4.(d) Why oil refineries are near the coast - Oil refineries are near the coast so crude oil can be brought to the refinery by ship and the finished products can then be transported by ship to the markets. 5. Why petrochemical works are often located next to the refinery - They are located next to the refinery so it is easy to move the raw materials to the factory. I appreciate your attention and interest in the topic.
