What Is Earth Science



What Is Earth Science

Topic I: Branches of Earth Science

A volcano erupts in Hawaii, destroying several homes and covering a major highway. An earthquake destroys a city in Central America. A three-kilogram meteorite travels millions of kilometers through Space and crashes through a roof of a home in Virginia. Tornadoes weave erratic paths through the Great Plains, causing loss of life and property. A hurricane lashes the Gulf Coast, resulting in floods and extensive coastal erosion. A tsunami batters the coast of Indonesia, drowning thousands. As a result of heavy rains, the Potomac River floods its banks causing flood damage in Old Town Alexandria, Virginia.

All of these occurrences are Earth Science events. The Earth is like a very complex machine. Each of the above occurrences impacts some “piece of the machine”, but they do not all impact the same “piece”, nor do they impact the Earth in the same way. Earth includes more than just the solid Earth. It also includes Earth’s oceans and atmosphere, as well as the Universe, of which the Earth is part. Over the course of the year, you will learn about the Earth and the processes and forces that change it, the materials from which it is made, its long history, and its place in the Universe.

The scope of Earth is vast. Dinosaur bones on display at museums were once imbedded in the rocks that make up some of the Earth’s cliffs and canyons. Mining certain rocks produces some of the gold used by jewelers and dentists. Computer models simulate the movement of the blanket of air that surrounds Earth so that scientists (meteorologists, to be more exact) can better understand the Earth’s weather. Ocean-floor exploration has led scientists to understand the movement of the Earth’s continents, as well as why tsunamis occur. And, the study of objects in Space has revealed much about our own planet. As you can see, there are many different areas of Earth Science. This broad field can be broken into five major areas of specialization of study: Astronomy, Meteorology, Geology, Oceanography and Hydrology.

The events mentioned above are studied by scientists who would “fit in” to one of the above areas of specialized study. To which “branch” of study of Earth Science do the events mentioned above belong? The volcano and earthquake are part of the discipline called Geology, the study of the Earth’s surface and interior. The meteorite belongs to the branch of Earth Science called Astronomy, the study of the Space. Tornadoes and the hurricane belong to Meteorology, the study of the Earth’s atmosphere. The tsunami belongs to the discipline called Oceanography, the study of the Ocean. The flooding Potomac River belongs top the discipline called Hydrology, the study of the Earth’s freshwater environments. Many, if not most, Earth Science events involve more than one branch of Earth Science. For example, the tsunami would be studied by scientists who study earthquakes, as well as those who study the waves caused by their occurrence in the ocean. As was stated earlier, the Earth is a very complex machine, and no event occurs in an isolated environment, where it does not have an impact on many different things.

Topic IA: Geology and the Activities of Geologists

Geology is the study of the origin, history and structure of Earth, and the processes that formed it and continue to shape it, today. Geology is the study of the materials that make up the Earth’s and the processes that form and change those materials. Geologists are scientists who study Geology. Geologists do things such as identifying rocks, studying the effects of glaciers, interpreting the Earth’s 4.6 billion year history. They explore Earth’s crust to discover new sources of oil, coal, Uranium and geothermal power, as well as other important metallic and nonmetallic minerals. They do research in forecasting earthquakes and volcanic eruptions. They make topographic maps showing details of Earth’s surface, and geologic maps to show Earth’s rock structure. Using data from spacecraft, geologists can even make maps of moons and planets.

Topic IB: Astronomy and the Activities of Astronomers

Astronomy is the study of objects beyond the Earth’s atmosphere. Astronomy is a discipline that studies objects and happenings beyond the physical reach of those who study it. Prior to the invention of the telescope and other technology, astronomers, scientists who study Astronomy, were only able to describe the position of objects in Space relative to one another. Today astronomers, with the benefit of telescopes such as Hubble, are able to study the Universe and everything in it.

Astronomers study the radiations sent out by objects in Space, and learn about the stars and planets from these radiations. Satellites, lunar explorers and space probes have been most useful to astronomers.

Some astronomers study the planets and their moons. Others devote all of their studies to comets, the study the origin of the Universe, or the life cycles of the stars. Still others work on ways of discovering whether life exists elsewhere in the Universe.

Some astronomers are fortunate to have “outer-space materials” to study. Astronomers, as well as geologists, study meteorites that have fallen to Earth. Apollo astronauts brought Moon rocks back to Earth. In addition satellites such as Mariner, Pioneer, Viking and Voyager have provided many photos and observations of members of the solar system.

Topic IC: Meteorology and the Activities of Meteorologists

Meteorology is the study of the air that surrounds our planet. Meteorologists, scientists who study the atmosphere, study the forces and processes that cause the atmosphere to change to produce weather. These scientists also predict the weather, and how changes in weather might affect the Earth’s climate.

Earth’s atmosphere covers Earth’s entire surface and reaches a height of hundreds of kilometers. The weather is created in its bottom layer. Today, jets fly above the weather, and satellites go much higher. Therefore, scientists are very interested in all of the layers of the atmosphere.

The meteorologists that we know best are weather forecasters. Behind these forecasters are those that study the effects of solar energy in changing the weather. Others, do research on hurricanes, thunderstorms and tornadoes. Still others are concerned with air pollution, global warming, and changes in climate, which means “long-term weather”. “Weather” describes the state of the atmosphere at a given moment.

Topic ID: Oceanography and the Activities of Oceanographers

Oceanography is the study of the Earth’s oceans, which cover nearly three-fourths of the Earth’s surface. Oceanographers, scientists who study the Oceans, study the physical and chemical properties of the oceans, as well as study the effects of human activity on Earth’s saltwater bodies. An oceanographer might study the behavior of an oil spill, for example. Oceanographers work from special research ships to measure the depth of the Ocean and map the ocean floor. They drill into the ocean floor to study its rocks and its history. They might attempt to locate deposits of valuable resources, such as oil. They also track ocean currents and chart the movements of icebergs. The do research to discover the effects of the ocean on weather and climate (El Nino). From studying tsunamis and undersea earthquakes, oceanographers are able to develop early warning systems for threatened coastal regions.

Topic IE: Hydrology and the Activities of Hydrologists

Hydrology, as it relates to this course, is the study of the Earth’s freshwater systems, both on and below the surface, and the movement of this water through the water cycle (Because Hydrology studies the movement of water through the entire water cycle, including saltwater, Hydrology, in reality, also includes the study of the ocean component of the Earth’s water. But, again, for this course, we will, for the most part, identify Hydrology as the study of the Earth’s freshwater systems). Hydrologists, scientists that study these freshwater systems, might study how to keep our streams, lakes, reservoirs, and subsurface water supplies from being polluted, and how to clean up the water that has already been contaminated. They might search for water supplies for cities or irrigated farms, or work to control river flooding or soil erosion. Others might study the movement of groundwater (water underground) to determine how best to protect the water supplies of those who rely on groundwater (water wells).

Topic II: Earth’s Systems

A system is a group of things that are studied as a whole. For example, the mouth, stomach, large and small intestines are part of the Digestive system. Each of the above organs is different, yet they “operate” together for a single purpose. The Earth is made up of many different “pieces”, yet most, if not all, of them are interactive with one another. Scientists who study the Earth have identified five main Earth systems: the Lithosphere, the Hydrosphere, the Atmosphere, the Biosphere and Space. Each system is unique, yet each interacts with the others. None of Earth’s systems is independent of the others, nor of the global system of the Earth itself.

Topic IIA: The Atmosphere

The Atmosphere is the blanket of gas that surrounds our planet. It is necessary for respiration by most living things. It also protects life by acting as a shield against harmful radiation from the Sun, and helps to maintain a temperature that is suitable for life. The atmosphere contains about 78% nitrogen, 21% Oxygen and 1% water vapor, Carbon Dioxide and trace gases.

Topic IIB: The Biosphere

The biosphere includes all living organisms on Earth, as well as the environments in which they live. At this time, Earth’s biosphere is the only known biosphere. Scientists have not yet found evidence of life, past or present, on other planets in our solar system, or others. However, we have barely “scratched the surface” in this area of exploration and discovery.

Topic IIC: The Lithosphere

The Lithosphere consists of the solid and molten layers of the Earth, and includes all of the nonliving, inorganic material that makes up our planet (rocks, minerals and molten material). More technically, from the perspective of the Earth’s layers, the Lithosphere is only the solid, upper layers of the Earth’s surface and interior, but from the perspective of Earth’s systems, the Lithosphere is all solid or molten inorganic rock-forming material that makes up the Earth.

Topic IID: The Hydrosphere

The Hydrosphere consists all of the Earth’s water, which includes the Earth’s oceans, seas, lakes, rivers and streams, groundwater, glacial ice and atmospheric water. 97% of all of the Earth’s water is saltwater. The remaining 3% is fresh water contained in glaciers, lakes, rivers and groundwater. About 75% of Earth’s freshwater is contained in glacial ice in mountains, Iceland, Greenland and Antarctica. Most of the rest is found as groundwater. Only a fraction of the Earth’s freshwater is in lakes and rivers.

................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download