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Explore the study of Earth Science and its interconnected systems. Learn about the Earth's past, present, and future, as well as the interactions between its geosphere, hydrosphere, biosphere, and atmosphere. Discover how scientists use observation, models, and technological advances to gain a comprehensive understanding of our planet.
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Science is: Any system of knowledge which tries to observe, identify, understand and describe the nature of the Universe in whole or part.
What is Earth Science?? Earth Science is the study of our entire planet, its past history, and how it has changed, its presentactivity, and the way that it will change in the future.
Earth Science is the study of our planet’s interacting systems (the geosphere, hydrosphere, biosphere and atmosphere) , its place within the solar system, and the universe beyond the earth. We study Earth Science so that we can learn how to live with the Earth, and make use of its resources.
The Earth’s Four Spheres Geosphere
Matter and energy move back and forth between the different Earth Spheres, and the different spheres interact every day, all around you. Can you think of some examples of how this is so?
Interactions among the Spheres Volcanoes (___________) erupt, sending ash and gases into the air (____________), and sending lava and ash down on surrounding forests (____________) and human habitations (____________).
Interactions among the Spheres Hurricanes (____________) Sweep across the ocean (____________), and onto the Land (____________), damaging The dwellings of people (____________) who live along The coast.
Interactions among the Earth’s spheres change the spheres to differing degrees. • These impacts can be single events, temporary changes, or ongoing. • We study these interactions through a number of different ways. • observations • models • as systems
Advances in technology have allowed scientists to observe (study) the Earth’s interactions in a variety of different ways. Submersible Satellite Seismometer
Satellites and space craft allow us to view, photograph and map Earth from Space.
Submersibles and ships allow us to view, photograph and map the ocean floor.
Buoys and other monitoring devices provide us with data related to events such as tsunamis and earthquakes.
Powerful computer programs called GIS (Geographic Information Systems) help scientists organize, layer and interpret huge amounts of collected data in order to study how the Earth changes over time.
The information collected from this technology has provided scientists with an understanding that the Earth’s spheres are strongly connected and interactive, and that the Earth is more than a collection of separate parts.This new method of studying the Earth is called: Earth Systems Science.
Using data from modern technology, scientists can create complex representations of how the Earth and other parts of our Universe “work”. • These representations of Earth processes are called models and systems.
What is a Model? A model is a simplified representation of an object, process, or phenomenon, used as the basis for further study or investigation.
What is a System? A System is defined as: A part of the Universe that can be studied separately. The Solar System
System models can be used to study what happened in the past, what is currently happening, and what might happen in the future. Galactic Collision
Two Types of Systems • Open System: System and its surroundings freely exchange both matter and energy. (examples?) • Closed System: Energy may enter and leave, but matter does not. (examples?) What is the Earth?
Earth Systems Science studies the flow of matter and energy in and out of the Earth’s open systems, or Spheres.
Cycles and the Earth A Cycle is a series of steps that repeats. Some cycles (water cycle) repeat over relatively short periods of time, while others repeat over millions of years. On Earth, the water cycle, energy cycle, carbon cycle, tectonic cycle and rock cycle “work” together to maintain a dynamic planet.
Water Cycle Review • Most of Earth’s water is in liquid form in the ocean • Water evaporates, turning to a gas (water vapor) • Water vapor eventually condenses, forming clouds that yield precipitation (rain, snow, etc.) • Rain may flow over the ground and into a body of water. This is called runoff. Water can also soak into the ground and be stored as groundwater.
The Carbon Cycle • The carbon cycle is a biogeochemical cycle. • In a biogeochemical cycle a chemical changes as it moves through the Earth system. • Carbon is call the building block of life. • It is present in all organic material and materials derived from things that were once living. • Carbon can be a solid or a gas. • Carbon changes form as it moves through the Earth’s 4 spheres.
The Energy Cycle • The water and carbon cycles are like wheels, with the water and carbon continually moving back and forth between the four spheres. • The Energy Cycle is different, it is more like a scale you would use in the laboratory. You are looking for the two sides of the scale to be balanced, the Earth system works in a similar way in regards to energy. • The amount of energy that enters should equal the energy that is removed. Because of the balance-scale nature of Earth’s energy cycle it is referred to as Earth’s Energy Budget. • There are three main sources of energy for the Earth: • Solar, geothermal, and tidal
Solar Energy (99.895%) • Comes form the nuclear fusion reactions in the Sun • Drives the winds, the ocean currents, and waves • Source of the energy that causes rocks to weather (forming soil)
Geothermal Energy (0.013%) • Originates in the Earth from the decay of radioactive materials • Drives the movement of continents, powers volcanoes, geysers, and earthquakes
Tidal Energy (0.002%) • A result of the pull of the Moon on Earth’s oceans • Slows down Earth’s rotation and causes the oceans to bulge
The Energy Budget • To maintain the balance of the energy budget, the incoming energy must go somewhere. • About 40% is reflected back into space without being changed. • The remaining energy is used within the Earth system. • As energy moves through the Earth system, it is changed. With every change a little bit of energy is lost.
The Effects of Earth’s Surface Different parts of Earth reflect solar energy of various rates. The percentage of energy that is reflected with out being changed is called Albedo. • A forest has a low albedo, reflecting 5-10% of the energy that reaches it. • A desert area reflects about 50% of the energy that reaches it. • A field of freshly fallen snow reflects 80-90% of the energy that reaches it.
The Effects of Earth’s Surface Earth’s overall albedo is about 30%. In contrast, the Moon’s albedo is about 11%, while cloud-covered Venus has an albedo of about 75%. An area’s albedo can change over time. • Thick snow or ice cover raise the albedo as does plowing a meadow for crop planting, or clearing a forest area for new homes. • Converting farm land back into a meadow or reforesting an area lowers the albedo.
Human Activity an the Cycles • Remember the water, carbon, and energy cycles not only interact with each other, but they are also affected by human activity. • Humans can alter the albedo of an area (which affects the Earth’s energy budget. • By burning fossil fuels, human put more carbons dioxide into the air, yet by planting trees and vegetation we also help to remove carbon dioxide from the air. • Damming rivers can lengthen the time it take for a water molecule to travel through the water cycle.
