Il Pianeta Azzurro: Le Acque sul Nostro Pianeta PDF

# Il pianeta azzurro: Le acque sul nostro pianeta ## Il pianeta azzurro - The Earth is called the "blue planet" because 71% of its surface is covered by water, while only 29% is occupied by land. - Water is essential for life and is found in all its forms on Earth: liquid, solid, and vapor. - Th...

# Il pianeta azzurro: Le acque sul nostro pianeta ## Il pianeta azzurro - The Earth is called the "blue planet" because 71% of its surface is covered by water, while only 29% is occupied by land. - Water is essential for life and is found in all its forms on Earth: liquid, solid, and vapor. - The Earth's oceans are the largest store of water on the planet, containing approximately 97% of all the water on Earth. - The remaining 3% is found in freshwater sources such as lakes, rivers, and groundwater. ## Acque globali (Idrosfera) - **Continental water** (3%): This includes rivers, lakes, glaciers, and groundwater. - Glaciers and permanent snow: 72% - Groundwater: 24% - Lakes, rivers, and water vapor: 4% - **Oceanic water** (97%): This includes the oceans and seas. ## L'acqua: una risorsa preziosa - Water is a valuable natural resource that we use for drinking, agriculture, industry, and many other purposes. - Only 0.3% of the world's freshwater is readily available for human consumption due to its location, contamination, and other factors. - Water is not evenly distributed across the planet, and in some areas, it is very scarce. ## Le acque oceaniche - **Oceans** are vast bodies of saltwater that surround the continents. - **Seas** are smaller bodies of saltwater that are enclosed or partly enclosed by land. ### Salinity - The salinity of seawater is higher than that of freshwater due to the presence of dissolved salts. - The average salinity of seawater is about 35 grams of salt per liter. - Salinity can vary depending on location, latitude, and other factors. ### Temperature - The temperature of seawater varies with depth, season, and latitude. - Surface water is generally warmer than deep water due to solar radiation. - The **thermocline** is a zone of rapid temperature change between the surface and deep water. ### Color - The blue color of the sea is due to the way water absorbs and reflects light. - Red light is absorbed first, followed by orange and yellow. - Blue light is absorbed the least, so it scatters back toward our eyes, giving the ocean its blue hue. ## I ghiacciai - **Glaciers** are massive bodies of ice that form from the accumulation of snow and compress into ice over many years. - **Perennial snow line**: The elevation above which snow persists year-round. - Glaciers are not static and move slowly down valleys due to gravity and the pressure of their own weight. - **Crevasses**: Deep cracks in the surface of glaciers caused by movement and tension. - **Types of glaciers**: - **Mountain glaciers**: Found in mountainous areas. - **Polar glaciers**: Found in Greenland and Antarctica, covering vast land areas. ## I ghiacciai italiani - Italy is home to numerous glaciers located primarily in the Alps and one in the Apennines. - The largest glacier in Italy is the Adamello Glacier, located in the Alps. - Glaciers are shrinking due to climate change, with some glaciers losing up to 30% of their surface area over the past 50 years. ## Le acque sotterranee - **Groundwater** is water found beneath the Earth's surface in rock formations and soil. - **Aquifers**: Underground layers of permeable rock or sediment that contain groundwater. - **Types of aquifers**: - **Phreatic aquifers**: Unconfined aquifers where the water table fluctuates with rainfall. - **Artesian aquifers**: Confined aquifers where groundwater is under pressure and can rise to the surface without pumping. ## I corsi d'acqua - **Rivers** are natural flowing bodies of water that originate from sources such as springs, glaciers, or rainfall. - **Torrents**: Fast-flowing rivers, often found in mountainous areas. - **Rivers** become wider, flow slower, and deposit sediment and minerals in lowland areas. - **Meanders**: Large loop-like bends in the course of a river in lowland areas. - **Mouth**: The end of the river, where it flows into a lake, ocean, or another body of water. ## I laghi - **Lakes**: Bodies of water surrounded by land, formed by various geological processes. - **Basins**: Depressions in the Earth's surface where lakes form. - **Inlet**: A stream or river that flows into a lake. - **Outlet**: A stream or river that flows out of a lake. - **Ponds**: Smaller, shallower bodies of water, often formed by natural processes. - **Swamps**: Low-lying areas of land saturated with water, often characterized by vegetation. ## L'inquinamento delle acque dolci - Various human activities pollute freshwater sources such as rivers, lakes, and groundwater. - Pollution sources include: - Agricultural runoff - Industrial waste - Sewage - Stormwater runoff - Pollution can harm aquatic life, damage ecosystems, and affect human health. ## Il ciclo dell'acqua - The **water cycle** is a continuous process that describes the movement of water on, above, and below the Earth's surface. - **Steps in the water cycle**: - **Evaporation**: Water changes from a liquid to a gas (water vapor) due to heat. - **Transpiration**: Water vapor is released from plants. - **Condensation**: Water vapor in the air cools and changes back into liquid water, forming clouds. - **Precipitation**: Water falls from clouds as rain, snow, sleet, or hail. - **Infiltration**: Precipitation soaks into the ground, becoming groundwater. - **Runoff**: Water flows over the surface, eventually reaching rivers, lakes, and oceans. ## Studia con le immagini - This page features diagrams illustrating the water cycle. - Questions prompt students to consider the processes involved in the water cycle and the differences between water sources. - These images visually demonstrate the interconnectedness of all water sources on Earth.