Wednesday, August 22, 2012

What is Earth Sciences and the History of It [sciencetechnology-center.blogspot.com]

What is Earth Sciences and the History of It [sciencetechnology-center.blogspot.com]

Earth Sciences

The name earth sciences refers in general to all scientific fields that study the earth and its atmosphere. They include geography, geology, geophysics, as well as scientific branches of mineralogy, oceanography, and meteorology. All of them are closely linked not only to each other but also to related sciences. The most important related sciences are chemistry, physics, biology, and history.

Within the framework of various segments, geology deals mainly with the rocks of our Earth (petrography), both on the surface as well as in the interior of the earth. It involves the study not only of the present state but also of how it was in the past and how it has changed during the course of Earth's history - how it happened, etc. It includes the impact of exogenous forces such as the sun, wind, water, and ice; and endogenous forces such as convective flows in the interior of the earth, volcanic activity, earthquakes, plate tectonics, etc. Pa leontology studies plant and animal fossils and thus acquires knowledge of the past. This knowledge provides valuable help for geological dating (historical geology).

Geophysics utilises in its study of the Earth the knowledge acquired by physics. It includes, among other things, a study of the earth's magnetic field, the earth's temperatures, the effects of the moon on the tides (high tide and low tide), and the study of the earth's gravity. Predicting earthquakes (seismology) and volcanic activity is also of the of tasks of geophysics. Meteorology, another area of geophysics, deals with the study of the Earth's atmosphere. Here, the study of the climate and weather forecasting play an important role.

Geography deals with the study and description of the Earth's surface. It is divided into two parts: one is the general geography dealing with the Earth's phenomena on a global basis, the other is the regional geography which concentrates on the specifics of a give n region.

Earth sciences also includes oceanography. Oceanography studies oceans, that is to say, it studies their chemical and physical properties and their currents. It also deals with the relationship between oceans and the climate, raw material deposits underneath the ocean bed, pollution in the oceans, and other issues.

In addition, there are numerous branches, such as soil science, geodesy, cartography (map-making), geography of plants, geoinformatics, aerial survey of the Earth, and many others. A great and diverse number of institutes and research centres are dedicated to acquiring continuously new information which is in part important also for the future of the human race, in particular when it concerns climate changes, environmental damage, and other areas of vital importance.

History of Earth Sciences

Ancient geology, which mainly studied the structure of the earth with its composition, formed part of natural philosophy. The questio n of the Earth's origins was always in the foreground.

Natural phenomena such as earthquakes and volcanic eruptions were being linked to gods and goddesses. As early as in the 6th century before Christ, Greek philosopher and astronomer Anaximander of Millet developed a theory that the universe, and therefore the earth as well, consists of concentrically arranged cylinders. Greek poet and philosopher Xenophanes discovered that, ages ago, fossilised seashells were made from the imprint of animals. Around 100 B.C., people began to realise the link between the tide and the moon.

Fossils played an important role when acquiring new information in medieval times as well. In linkage to the work of N. Stensen, a Danish naturalist, the year 1669 marks the beginnings of modern geology in that he determined that the upper layers of the earth are younger than the lower layers. He also ascertained that earth layers originally deposited horizontally were fractured and deformed by the internal forces of the Earth.

Modern geology of the 18th century noted a definite separation between the bible's notion of creation and earth's actual history. The first geological map of a specific region was made (by Füchsel, in 1761). A discussion ensued with regard to whether all rocks were the result of the action of water or of volcanic activity. In 1875, thanks to the efforts of Eberhard Süß, the first comprehensive theory concerning the origins of mountains was proposed. At that time, it was still assumed that the Earth is continually contracting, thus causing the "folding" of the mountain ranges (contraction theory).

The discovery of radioactivity in the 20th century provided a new method of dating of the rocks. Alfred Werner, with his idea about continental shift, introduced a new line of thought concerning the origins of great mountain ranges. This approach was later incorporated in the lithospheric plate tectonics, which today is generally a ccepted.

In the field of geography (branch area) dealing with the description and interpretation of the surface of the earth, Egyptians, Chinese, and the Phoenicians already explored unknown regions during their far-reaching trips. In the 4th century B.C., Aristotle determined that the Earth is round. Eratosthenes (276-196 B.C.) was the first person to calculate the earth's circumference. In the 2nd century A.D., Greek astronomer Ptolemy compiled a wealth of geographical information gathered by Greeks and Romans during their conquering wars and travels.

No major advancement of science was registered in the early Middle Ages because there was only a small number of exploratory travel. New and important discoveries, however, came about in the 13th century with Marco Polo, and the in the 15th and 16th centuries with the explorations of the Spanish and Portuguese seafarers along the African coast. At that time, it was recognised beyond any doubt that the earth is a s phere and not a cylinder, as it was previously assumed.

For a long time, the work of the German geographer Varenius, who categorised geography into three parts, was considered to be the cornerstone of science. The first part concerns the study of the earth's shape and size; the second one deals with the seasons, climate, and the tide in relation to the position of the earth in the universe; and the third part concentrates on comparing the various regions of the Earth.

In the 18th century, Immanuel Kant ,and in the 19th century Alexander von Humbolt, were among those whose work in various branches of the science of geography resulted in an important progress of this science. At that time there was a proliferation of geographic societies and magazines which supported the science by publishing and disseminating new geographical knowledge. At the start of the 20th century, the old methods were still used. Later on, new geographical knowledge started to be evaluated u sing mathematics and statistics.

Beginning in the 1960s, the development of modern computers facilitated the compilation, analysis, and, most importantly, the storage of geographical data. Today, computer simulations play a very important role.

Find More What is Earth Sciences and the History of It Topics

Question by Bryanna B: How can I find field work in environmental science? I am a college student majoring in Environmental Science. I want to do some field work for experience, but have no idea where or how to find it. I live in San Antonio, TX if that matters. I am just now taking my first Environmental Science course-- should I wait until I know a little more about the field to do field work? Best answer for How can I find field work in environmental science?:

Answer by geoweeg
Check with your professors. They should be able to tell you about internship positions. You may also ask them if any of them need a research assistant (since they will be doing field work as well). At the intern level enthusiasm is just as important as how many classes you've had.

Answer by Dana1981, Master of Science
It's probably better to wait until you have a few ES courses under your belt. That way a company will be more likely to take you on as an intern. Then just search for environmental consulting companies in your area, contact them and explain your background (i.e. ES classes) and that you want to get some experience in field work and see if they'll let you intern. Make sure you specify that you want to do field work, because we usually make our interns do boring stuff like filing!

Answer by Kat
i dont know if this is in line with your major, but my brother use to work for the edwards aquifer. maybe they might have an internship.

Answer by Buddha
I am environmental student myself and I know it is very difficult to get a job in this field due to the high job competition and lack of level entry positions (if someone told me earlier). Most of friends with same qualifications got the job through networking or by luck. I recommend training your skills where the jobs and money is in environmental industry which is mainly mining, government work (if you are lucky) and consulting. Environmental conservation is enforced by law not the good will of employers, profits come first. Choose which area to get work experience wisely. Good Luck

â€" [Science]

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