An introduction to Earth Science

 

What is Earth sciences?

 Earth science concerns about understanding  the spherical ball on which we live. Earth is a very large, complex set of systems. So most Earth scientists study single aspect of the planet. . The major branches of Earth science are described below.

1-Geology

Geology is the study of the solid Earth origin,history and structure of the Earth, 
-Geologists study:

- how rocks and minerals form. 

-The way mountains rise up is part of geology. 

-The way mountains erode away is another part. 

- fossils and Earth’s history. 

-There are many other branches of geology. There is so much to know about our home planet that most geologists become specialists in one area. For example, a mineralogist studies minerals.

                                                             Mineralogy

Some volcanologists brave molten lava to study volcanoes. 

Seismologists monitor earthquakes worldwide to help protect people and property from harm

 Paleontologists are interested in fossils and how ancient organisms lived. Scientists who compare the geology of other planets to Earth are planetary geologists. Some geologists study the Moon. Others look for petroleum. Still others specialize in studying soil. Some geologists can tell how old rocks are and determine how different rock layers formed. There is probably an expert in almost anything you can think of related to Earth!

Geologists might study rivers and lakes, the underground water found between soil and rock particles, or even water that is frozen in glaciers. 

Earth scientists need geographers who explore the features of Earth’s surface. They work with cartographers, who make maps. Studying the layers of rock beneath the surface helps us to understand the history of planet Earth .

Geologists ask a lot of questions. They wonder what they need to know about earthquakes to be able to predict them in time to evacuate a region. They ask what will happen to shorelines as sea level rises. Some even wonder what would happen if the magnetic field reverses!

These folded rock layers have bent over time. Studying rock layers helps scientists to explain these layers and the geologic history of the area.

Oceanography

Oceanography is the study of the oceans. The word oceanology might be more accurate, since “ology” is “the study of.” “Graph” is “to write” and refers to map-making. But mapping the oceans is how oceanography started.

More than 70% of Earth’s surface is covered with water. Almost all of that water is in the oceans. Scientists have visited the deepest parts of the ocean in submarines. Remote vehicles go where humans can't . Yet much of the ocean remains unexplored. Some people call the ocean “the last frontier.”

There are many branches of oceanography. 

1-Physical oceanography is the study of water movement, like waves and ocean currents. Physical oceanographers ask when or if a tsunami will hit a shoreline.
2-Geological Oceanography • Study of earth at edge of ocean • Formation processes (seafloor) • Sediments • Rocks & minerals • Geothermal vents Marine geologists look at rocks and structures in the ocean basins. These scientists ask how new ocean crust forms. 
3-Chemical Oceanography • Composition & history of seawater • Seawater processes & interactions • Salinity • Dissolved gases • Nutrients
Chemical oceanographers study the natural elements in ocean water. Chemical oceanographers might be concerned with where carbon dioxide goes in the oceans.
4-Biological Oceanography • Living organisms • Organisms relationships with each other and their environment,Marine biologists look at marine life.  
 Marine Sediments (geological) • created by • Living Organisms (biological) • That are influenced by • Nutrients (chemical) • and • Currents & Temperature (physical)
Why Study Oceanography? 

• Earth is the water planet 

• Oceans Modulate the Climate 

• Human Civilization (waves govern the coastal processes and habitat) The Oceans cover ~71% of earth’s surface and have an average depth of ~3.8 km; carry most (80-97.5%) of the hydrospheric water supply.

Meteorology and Climatology

Meteorologists don’t study meteors—they study the atmosphere! The atmosphere is a thin layer of gas that surrounds Earth. The word “meteor” refers to things in the air. 

Meteorology includes the study of weather patterns, clouds, hurricanes, and tornadoes. Meteorology is very important. Using radars and satellites, meteorologists work to predict, or forecast, the weather. Meteorologists are getting better at predicting the weather all the time. Meteorologists wonder how to better predict weather. They wonder what the effects of rising water vapor in the atmosphere will be on weather.

Meteorologists forecast the weather a region can expect from a tropical storm.

Climatology studies the whole atmosphere, which is a thin layer of gas that surrounds the Earth. Most of it is within about 10 – 11 kilometers of the Earth’s surface. Earth’s atmosphere is denser than Mars’s thin atmosphere, where the average temperature is -63° C, and not as thick as the dense atmosphere on Venus, where carbon dioxide in the atmosphere makes it hot and sulfuric acid rains in the upper atmosphere. The atmosphere on Earth is just dense enough to even out differences in temperature from the equator to the poles, and contains enough oxygen for animals to breathe.

Over the last several decades, climatologists studying the gases in our atmosphere have found that humans are putting higher levels of carbon dioxide into the air by burning fossil fuels (Figure 1.14). Normally, the atmosphere contains small amounts of carbon dioxide, however, with increases in the burning of fossil fuels more than normal amounts are present. These higher concentrations of carbon dioxide can lead to higher surface temperatures. Much of climate change science is based on the increases of greenhouse gases, like carbon dioxide, in the atmosphere and the effect those higher concentrations have on global temperatures.  Climatologists can help us better understand the climate and how it may change in the future in response to different amounts of greenhouse gases and other factors 

-Climatologists also study the atmosphere. These scientists work to understand the climate as it is now. They also study how climate will change in response to global warming. There are lots of questions to ask about our changing climate.

Environmental Science

Environmental scientists study the effects people have on their environment. This includes the landscape, atmosphere, water, and living things. These scientists ask all sorts of questions about how Earth systems are changing as a result of human actions. They try to predict what changes will come in the future.

Ecologists study lifeforms and the environments they live in . They try to predict the chain reactions that could occur when one part of the ecosystem is disrupted.

In a marine ecosystem, coral, fish, and other sea life depend on each other for survival

Astronomy

Astronomy is the study of outer space and the physical bodies beyond the Atmosphere Astronomers use telescopes to see things far beyond what the human eye can see. Astronomers help to design spacecrafts or satellites that travel into space and send back information about faraway places.

Astronomy

*Astronomers ask a wide variety of questions. :

-How do strong bursts of energy from the Sun, called solar flares, affect communications? 

-How might an impact from an asteroid affect life on Earth?

- What are the properties of black holes? 

-Astronomers ask bigger questions too.:

- How was the Universe created?

- Is there life on other planets? 

-Are there resources on other planets that people could use for space travel? 

-Astronomers use what Earth scientists know about our planet to make comparisons with other planets.