Understanding Earth's Systems

Water is one of the essential components necessary for life to exist on Earth. All of Earth's water in all its states, frozen, liquid, and gaseous, make up the hydrosphere. Liquid water exists on the surface of the earth but there are also reservoirs of water underground. Frozen water exists as glaciers, ice caps, and icebergs. This water makes up a special subcategory of the hydrosphere called the cryosphere. Water can even be found in the atmosphere in the form of water vapor. Readers will come to understand how the water cycle tracks water's movement from one phase to the next.

Earth's atmosphere plays a very important role in sustaining life on the planet. The atmosphere is made of a very thin layer of air, which covers every inch of Earth's surface up to the edge of space. The atmosphere is comprised of different chemicals and compounds at any given location, which also means that the atmosphere behaves in different ways at any given location. This book explores the atmosphere's composition, its behavior, and how it affects life on Earth.

The biosphere refers to the parts of Earth where life exists or where known life has existed in the past. The biosphere is comprised of the atmosphere, geosphere, and hydrosphere because life exists in each of those three spheres, from birds in the sky to fish in the water to worms in the dirt. Food chains represent interconnected life cycles in the biosphere. Energy is transferred from one organism to the next and, as apex predators die, nutrients are returned to the soil. Readers will learn how people affect the biosphere and how life and energy are maintained in the biosphere.

Earth's geosphere is made up of the planet's interior, rocks and minerals, landforms, and the processes that shape Earth's surface. The interior is comprised of many different sections, including Earth's core and crust. Readers will learn about types of rock, including igneous, metamorphic, and sedimentary rocks, and how they come together to form the rock cycle. There are many different types of minerals found inside Earth, some of which form the world's most precious gems, such as diamonds. The movement of tectonic plates inside Earth creates mountain ranges as well as drives the rock cycle. This book will help you fulfill standards in the earth science curriculum.